Learning to Tune the Holley Sniper

Here is what the learn table looked like after ~15 minutes with weendoggy's config yesterday:

https://thefactoryfiveforum.com/atta...9&d=1589117810

Compare that with the learn table that was there since the beginning:

https://thefactoryfiveforum.com/atta...7&d=1588619960

If you've followed my build, you'll recall that my car has experienced some rough patches with fouled plugs and running hyper rich, so the learn table that was in the Sniper before starting this exercise included data from all those "bad" events.

After essentially getting back to square one and letting the Sniper start to relearn what it wants based on the default tune, we are going to start addressing one thing at a time. We're starting with the area that was doing the popping on decel (coast). As I mentioned above, after resetting the learn table, the car was better. Now we can focus on the AFR for those points without all the accumulated issues that my old learn table had in it. To start, we isolated the vacuum (kPa) and rpm range that I can easily replicate as I leave my home and coast down a long hill. We decided to try to increase the values for this vacuum/rpm range in the Target A/F Ratio table and see how the car responds.

Here is the Before table:

https://thefactoryfiveforum.com/atta...5&d=1589310640

Here is the After table:

https://thefactoryfiveforum.com/atta...4&d=1589310631

The goal of this change is to lean the specific area of the learn table shown here:

https://thefactoryfiveforum.com/atta...6&d=1589310880

Hey guys! I haven't given up on this. I'm recovering from a surgery and can't work on the car right now, but will pick this up again in a week or so if all continues to go well with my recovery. I will say that adjusting the area in my previous post didn't produce the results I was hoping for. I did capture a short datalog that likely explains why, however. I had adjusted the 1000-1750 rpm range and as you can see in the data capture, the high AFR condition I can easily replicate that I'm associating with the popping when coasting down the hill just down the road from my driveway was produced at ~2000-2500 rpm, right after shifting into 3rd gear and the manifold pressure is at it's lowest (highest vacuum) in the 20-30 kPa range.

https://thefactoryfiveforum.com/atta...5&d=1589989409

Data log and config file for this post are attached.

Today I decided to tackle this issue from a different angle. As I had mentioned at the beginning of this thread, the car was running pretty well with the exception of the popping that I want to clear up. So, I reverted to the tune I saved from the ECU before I started with any of this. First, I let the car warm up and then did a short drive to see where it was and as it should be, it was back to what I was used to. Next, I transferred the learn table to the base and went for another drive where the car continued to feel pretty good, but still popping on coast. I then started to add fuel in the areas of the base table where the popping was most prevalent and opened the learn parameters to 100% across the board. This time, the car was better with less popping, so one more tweak to add another small amount of fuel in a very small region of the base table, and it is even better. I'm going to drive it for a while now to let it learn some more and see how it does.

Papa Dave,

I applaud your persistence to Outwit The Sniper; however, the more I see the trouble folks have with them is likely going to keep me in The Carburetion Zone.
Also, I know you'll figure it out but remember that a lot of popping occurs when the air is rushing back into the pipes.
I remember guys causing this issue way back in the day when my hair wasn't gray when they would install Trans Am Tips on their hot rods.
That expansion of the exhaust combined with new tip would to let in just enough air in to cause some popping conditions with only that one little change.

My Question Are:
1. How Is The Car Running?
2. Is The Popping Causing Any Stumbling?
3. Could A Fresh Set Of Plugs Be Worth Installing?
4. Is the Engine Passing Unspent Fuel To The Pipes Because A Plug Is Fouled?

Good Luck & Please Keep Us Posted!

Steve

Steve,

The open flowing exhaust may ultimately be what's contributing the most to the popping I'm getting. Other than the popping and higher than desired idle right now, the car is running great. It starts right up and idles with no fuss. I have no stumble, hesitation, misses, smoke, or any other drivability issues. To me, the effort to learn to tune the EFI is no different than if I had installed a carb and wanted to learn how to tune that. The difference is that with the EFI, I can see what is happening and with a carb I'd need to learn to feel and listen for those subtle changes that let a pro dial in the "perfect" tune. With EFI, once I get it where I want it, it's more likely to stay that way than a carb since the EFI is making 1000 tiny adjustments/second to keep the air/fuel ratio in the target range as conditions change and a carb's tune is essentially good only for the specific conditions at the time the last adjustment was made.

After doing a lot of reading on the Holly Sniper EFI forum and discussing with a couple of guys there, the popping can be caused by a number of conditions. One, which we already discussed, is a free flowing exhaust. Others could be running too rich or too lean. When I started chasing this, I made an assumption the car was running too rich and was letting unburnt fuel into the pipes. We tried to lean it out by modifying the AFR target map and that exacerbated the popping. So, I decided to go the other direction and richen the mixture in the small areas of the fuel table where the popping occurred and it's improving. This makes sense to me because I could stop the popping at any instant by just giving the throttle a little squeeze. Of course, there is a point where too much fuel would start causing other issues, so I'm taking it slow and will see what happens as the learn table repopulates with the new base fuel settings. The awesome thing is, every time I change something, I can save that tune. Likewise, I can easily get back to any known starting point in a few seconds by loading the proper tune back into the ECU.

Dave

I wonder if adding a pair of Exhaust Cones at the exit point of the side pipes could stop the pop?

https://www.summitracing.com/search/...ibanner=SREPD5

I had a Meanstreak 1600 for over a dozen years (2005 Model) and changed the exhaust to a two into one set up.
With the Exhaust Cone in place I'd get minimal popping, but pull the sucker out and it would pop away.
The bike ran fine either way, but I kept the cone baffle in because of the popping.

Hummmmm?????

Steve

Quote:

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Originally Posted by GoDadGo

I wonder if adding a pair of Exhaust Cones at the exit point of the side pipes could stop the pop?

https://www.summitracing.com/search/...ibanner=SREPD5

I had a Meanstreak 1600 for over a dozen years (2005 Model) and changed the exhaust to a two into one set up.
With the Exhaust Cone in place I'd get minimal popping, but pull the sucker out and it would pop away.
The bike ran fine either way, but I kept the cone baffle in because of the popping.

Hummmmm?????

Steve

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Steve,

That might be an option if I can't tune the popping out. I'm really only trying to eliminate the popping under coast. I can live with the popping on down shifts. Evidently, some guys try to tune their cars to induce the popping. To each his own I guess.

Dave

I got the car out today and drove it about 50 miles in mixed driving conditions and it is definitely better than it was before I started bumping up the fuel in the "popping" areas. I'll pull the tune off the ECU later and see what the learn table is looking like after today's drive. I didn't do any data logging today. I feel like I'm definitely headed in the right direction now.

Wow Dave, I just read through this... I have a headache... I'll be curious to see what your MPG ends up being. With mine, same engine, with the Holley Carb, I've been very consistent at 17mpg over the past 10,000 miles. I would think once you get all the tuning done, you'll be up over that. I'm so glad I have the carb... :-)

Quote:

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Originally Posted by Papa

I got the car out today and drove it about 50 miles in mixed driving conditions and it is definitely better than it was before I started bumping up the fuel in the "popping" areas. I'll pull the tune off the ECU later and see what the learn table is looking like after today's drive. I didn't do any data logging today. I feel like I'm definitely headed in the right direction now.

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You've got the Patience & Determination of Saint!

In my Forte 347 with the Holley Sniper FI, the thermostat is 180 degrees and I think the fan is set to come on at 180-185. This means that the fan is always going to be running when the thermostat is open. Even on the highway. Is there an issue with this? I'm wondering if I should bump up the Sniper fan on trigger temperature to 195 or so. That way the fan can cycle on only when needed.

What are the thoughts of people who are way more knowledgeable than me about this?

My fan is set to come on at 190 and off at 180.

Quote:

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Originally Posted by Papa

My fan is set to come on at 190 and off at 180.

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When driving, is your fan only on when stopped or at low speeds at that setting?

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Originally Posted by TMartinLVNV

When driving, is your fan only on when stopped or at low speeds at that setting?

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Honestly, I can't hear it when driving the car unless I'm in town and stop & go situations in traffic. I keep my eye on the temp gauge and it does get up close to 200* in those situations, but drops right back down when the car is moving. It doesn't get as hot here as it does in Vegas.

Ok, I'll give your setting a try and see how it works. Once DMV opens :mad:

Thanks

Just came across this thread, great stuff. A little behind you at only 500 miles, but with similar issues of popping while decelerating (thought it was normal tbh). I've been trying to do some smoothing of the learn table but haven't noticed much difference. Overall, I feel like it's running strong, but I guess I don't know what what I may be missing.

You mentioned your idle is high? Do you mean it's idling high compared to what you've set your sniper idle at? Or just in general want to bring it down without it dying? I initially set my idle at 950, but it was actually idling at 1100 until I adjusted the idle screw until it read true. Since then I've backed it down to 875 which is about as low as I think I can go with my setup. Pretty lopey at that rpm.

I'm running a 427w with a pretty aggressive cam, sniper efi with full sniper ignition system and gp headers. Looking to get it Dyno tuned next weekend. Would like to grab a before and after of my tune to see what actually is changed.

My idle is right where I set it at 950rpm. I'd like to get it down around 800 if possible, but had issues with it when I originally had it lower. I've been able to clean up most of the popping by adjusting the base fuel table in the map/rpm region that the condition occurred in. I originally tried to lean it up by manipulating the target AFR table, but that didn't help. I spoke with one of the guys on the Holley forum who suggested I add fuel via the base table. That has made a big difference.

Let me know if you get the results you are hoping for with the tuner. I have one here that I can go to if I need to. One of the guys on the Holley forum has offered to do a remote tune, but I'd rather go with the local guy.

Quote:

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Originally Posted by Papa

My idle is right where I set it at 950rpm. I'd like to get it down around 800 if possible, but had issues with it when I originally had it lower. I've been able to clean up most of the popping by adjusting the base fuel table in the map/rpm region that the condition occurred in. I originally tried to lean it up my manipulating the target AFR table, but that didn't help. I spoke with one of the guys on the Holley forum tha suggested I add fuel via the base table. That has made a big difference.

Let me know if you get the results you are hoping for with the tuner. I have one here that I can go to if I need to. One of the guys on the Holley forum has offered to do a remote tune, but I'd rather go with the local guy.

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Dave,
You do have to look at both tables. Changing the AF is o.k. if the Base Fuel is close. If the BF is at 5 say, and you try to lean it out, it may be lean already and therefore taking more fuel away to meet your AF ratio. It's a trial and error when doing the tune by yourself as I said before. Easier with two people with one tuning and one driving of course, or the dyno. However, glad you're on your way. ;)

Quote:

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Originally Posted by Papa

My idle is right where I set it at 950rpm. I'd like to get it down around 800 if possible, but had issues with it when I originally had it lower.

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Dave, is the desire for 800 due to the EFI? I have the same engine and have my idle set at 650 and it seems to work great there for me.. But, I'm carbed...

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Originally Posted by BadAsp427

Dave, is the desire for 800 due to the EFI? I have the same engine and have my idle set at 650 and it seems to work great there for me.. But, I'm carbed...

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The EFI doesn't like that low of an idle. I started at around 650 rpm and after recommendations from others, bumped it up and it is much better. Now that the car is actually being driven, I think I can bring it down a bit.

Quote:

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Originally Posted by weendoggy

Dave,
You do have to look at both tables. Changing the AF is o.k. if the Base Fuel is close. If the BF is at 5 say, and you try to lean it out, it may be lean already and therefore taking more fuel away to meet your AF ratio. It's a trial and error when doing the tune by yourself as I said before. Easier with two people with one tuning and one driving of course, or the dyno. However, glad you're on your way. ;)

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Thanks weendoggy -- I know these tables all interact and it takes time. I suspect that adding fuel as I have may only address a symptom and not a cause, so I'm happy to keep tinkering as long as the car continues to run well. I may still just take it to a professional with a dyno and let them dial it in correctly. What are your thoughts on being able to drive at very high altitudes with the Sniper? Should I think about a separate tune for those conditions above 10-11,000 feet?

Dave

Quote:

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Originally Posted by Papa

Thanks weendoggy -- I know these tables all interact and it takes time. I suspect that adding fuel as I have may only address a symptom and not a cause, so I'm happy to keep tinkering as long as the car continues to run well. I may still just take it to a professional with a dyno and let them dial it in correctly. What are your thoughts on being able to drive at very high altitudes with the Sniper? Should I think about a separate tune for those conditions above 10-11,000 feet?

Dave

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If you keep in mind you're main driving is where you live at the 6K' altitude, setting it to run there is fine. I wouldn't worry too much if you just take occasional trips to the 10K' level. It may run a little boggy (less air), but it will run fine. If you find yourself taking more trips to that area, a 2D table to allow the change would be helpful. You'll find the same problem (more air) when you go to below 1K' as well, the same issue will rise up. Keeping the same AF is good and not the issue, the Base Fuel will need to be set. Air is the big culprit with it being less dense the higher and more dense the lower you go. Thus, the Base Fuel will need pampering every time, but for your occasional trips to these areas, unless you really want to setup tables, I'd leave it be once you dial into your main driving area. I live at sea level and my occasional trips to the Sierra's do pose some issues, but not enough for me warranting a change. If I did a lot of trips, I'd make a 2D table to adjust BF based on MAP settings. I would get it tuned well for your normal driving area and see how things go. If you need to change, or want to change, I'd do it after you have it tuned well. I don't think going to a dyno is really needed, but if that's what makes you comfortable, I'd go ahead. It won't hurt.

Glenn

Quote:

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Originally Posted by weendoggy

If you keep in mind you're main driving is where you live at the 6K' altitude, setting it to run there is fine. I wouldn't worry too much if you just take occasional trips to the 10K' level. It may run a little boggy (less air), but it will run fine. If you find yourself taking more trips to that area, a 2D table to allow the change would be helpful. You'll find the same problem (more air) when you go to below 1K' as well, the same issue will rise up. Keeping the same AF is good and not the issue, the Base Fuel will need to be set. Air is the big culprit with it being less dense the higher and more dense the lower you go. Thus, the Base Fuel will need pampering every time, but for your occasional trips to these areas, unless you really want to setup tables, I'd leave it be once you dial into your main driving area. I live at sea level and my occasional trips to the Sierra's do pose some issues, but not enough for me warranting a change. If I did a lot of trips, I'd make a 2D table to adjust BF based on MAP settings. I would get it tuned well for your normal driving area and see how things go. If you need to change, or want to change, I'd do it after you have it tuned well. I don't think going to a dyno is really needed, but if that's what makes you comfortable, I'd go ahead. It won't hurt.

Glenn

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Thanks, Glenn. I think I'd like to start experimenting with the idle speed next. Do I just get the car to operating temperature, adjust the setting in the ECU and then dial the idle screw to the desired setting?

Dave

Quote:

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Originally Posted by Papa

Thanks, Glenn. I think I'd like to start experimenting with the idle speed next. Do I just get the car to operating temperature, adjust the setting in the ECU and then dial the idle screw to the desired setting?

Dave

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Yes. Engine operating temperature. I doubt you'll be able to have that idle below 850rpm with good results. Depending on how radical your cam is, it may not like it. My Terminator runs at 850rpm +/- and has a nice lope. Any lower and it's a pig. I'd try that area nd set the ECU to confirm this is what you want.

You should run in Open Loop and tune the idle off the BF table (lbs/hr). Highlight a large block, maybe 20 or so, around the "football" (with it in the center of the cells) and then using your Up/Down arrows with the Ctrl key pressed, move the BF range up until the engine doesn't like it (note reading), then down until the engine doesn't like it (note reading) and then balance in between those readings. Ex: up and chokes out at 10, down and chokes out at 5, which would mean it likes a 7.5 area in the idle range. Now, this can be subjective, but gives you an idea on what to do. When doing the testing, move the arrow keys and wait a bit before moving again so you give the system some time in that area. 10-15 secs is good. Once you and the engine are happy, put the ECU back to closed loop. Save your file and just clear the Learn table and go for a drive. You can compare the new/old file to see what happened. Just save the new one different.

Glenn

Quote:

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Originally Posted by weendoggy

Yes. Engine operating temperature. I doubt you'll be able to have that idle below 850rpm with good results. Depending on how radical your cam is, it may not like it. My Terminator runs at 850rpm +/- and has a nice lope. Any lower and it's a pig. I'd try that area nd set the ECU to confirm this is what you want.

You should run in Open Loop and tune the idle off the BF table (lbs/hr). Highlight a large block, maybe 20 or so, around the "football" (with it in the center of the cells) and then using your Up/Down arrows with the Ctrl key pressed, move the BF range up until the engine doesn't like it (note reading), then down until the engine doesn't like it (note reading) and then balance in between those readings. Ex: up and chokes out at 10, down and chokes out at 5, which would mean it likes a 7.5 area in the idle range. Now, this can be subjective, but gives you an idea on what to do. When doing the testing, move the arrow keys and wait a bit before moving again so you give the system some time in that area. 10-15 secs is good. Once you and the engine are happy, put the ECU back to closed loop. Save your file and just clear the Learn table and go for a drive. You can compare the new/old file to see what happened. Just save the new one different.

Glenn

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850 would be a lot better than the 950 I'm at now. My cam isn't too crazy, but will lope a bit at low idle speeds. I'd started at ~700 with the initial setup that BPE used (FAST XFI Street), but that didn't work well and I was fouling plugs.

https://www.youtube.com/watch?v=doBle7rb7hI

When I initially set up the Holley, I was told to start with a higher idle, which is where the current 950 value was established.

weendoggy, You mention using a 2D table to correct for altitude changes. With my Holley HP ecu I was able to build a 2D table using BARO(barometer) parameter and alter timing, fuel, cranking fuel, etc. based on the actual reading, which solves the problem for altitude changes . However the Sniper does not have that parameter in the advanced tables or in the data log parameters. Apparently they didn't see a need to look at the absolute barometric pressure with the Sniper. I've not pursued any further though. Have you had any success doing this with the Sniper?

Bob

I adjusted the idle down to 850 rpm and drove the car into town with some stop & go traffic and it seems happy and sounds better than the higher idle at 950 rpm.

I got to take the car on a real drive, 270+ miles yesterday and I'm very pleased with the way the EFI performed. Listen to the first minute of this video and notice what you don't hear!

https://youtu.be/Ay8SRyLU6cY

Sure didn't hear any popping, then the music started and I fell asleep... LOL That is certainly relaxing. The car sounds good. So, what was the final resolution(s)?

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Originally Posted by bobl

Sure didn't hear any popping, then the music started and I fell asleep... LOL That is certainly relaxing. The car sounds good. So, what was the final resolution(s)?

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Hey Bob,

What I ended up doing per a recommendation from a guy on the Holley Forum was to start to add fuel in the RPM/MAP regions where I was getting the popping on decal. It was only a few cells of the base table that I adjusted a little at a time. Under certain higher RPM conditions, I'll still get some popping when down shifting, but not just under coasting conditions. I can live with that. Before making any adjustments, I went back to the tune that was first downloaded where the car was running good except for the popping. I cleared the learn table and adjusted the fuel up by 10% in the trouble areas and set the learn parameters to 100%. I then drove the car for about 20 minutes and merged the new learn table with the base. After about three iterations of this, I was happy with the way it was behaving and reduced the learn parameters down to 50% and have been running with that for about 400 miles now. I also dropped the idle down from 950 to 850 and like the way that is doing as well.

I know it isn't perfect, but it's so much better now that I think I'll leave it alone for a while. I'm still thinking about getting it to a professional tuner at some point.

Thanks to both you and Glenn and the guys over on the Holley forum for all the advice and your time helping me with this.

Dave

Hey Papa Dave,

Your Engineering Patience Is Showing!
By the time you're done, I'm sure you'll be the guy every Sniper fan is reaching out to on this forum.
On a related note, we had a gentleman from COBB Tuning give a presentation on their programming tools at the PCA meeting last night.
It was extremely interesting, though 100% NOT applicable to my ride, but I enjoyed the event immensely.
Glad You're Making So Much Progress With Your Snyper System Because I Know You'll Be Sharing Your New Found Knowledge!

Steve

I know some ricers that purposely lean out the bins in the lower map decel regions just to get it to pop like that. Personally I don't like that feature, so what you are doing by increasing VE (Richer) in those bottom bins is the right thing. I've not tuned many Holley Efi cars, mostly Megasquirt, but the theory is the same. What I would do is save your tune, then choose all those lower bins and increase the bottom two or three rows by 10% or so until it goes away on decel. Scott

I'm just starting to read up on all of the adjustments for the Sniper. My motor is running very well after I got the IAC adjusted correctly. I have almost 1000 miles on it. I hooked up the display controller and keyed on. The TPS reads 0% as it should. I depressed the pedal all the way to the floor and could only get 78% throttle. I then opened the throttle blades manually on the side of the throttle body and can get 79%. So I think that I have the pedal and cable adjusted correctly. In reading the Holley literature, I should be able to get 95-100% throttle at WOT.

What readings do you get at WOT? I'm thinking about calling Holley tomorrow morning to see if I can do anything else.

Also, my idle is right at 850-900. I was trying to lower it down to 750 or so as recommended by Forte's FI guy and my cam (Ford E cam). I started at 800, then 700 target idle speed but it does not change the idle down at all. When I turn in the idle screw, the motor starts to stumble when letting off of the throttle and the motor is cold (my original problem that I fixed by adjusting the same screw).

Quote:

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Originally Posted by TMartinLVNV

I'm just starting to read up on all of the adjustments for the Sniper. My motor is running very well after I got the IAC adjusted correctly. I have almost 1000 miles on it. I hooked up the display controller and keyed on. The TPS reads 0% as it should. I depressed the pedal all the way to the floor and could only get 78% throttle. I then opened the throttle blades manually on the side of the throttle body and can get 79%. So I think that I have the pedal and cable adjusted correctly. In reading the Holley literature, I should be able to get 95-100% throttle at WOT.

What readings do you get at WOT? I'm thinking about calling Holley tomorrow morning to see if I can do anything else.

Also, my idle is right at 850-900. I was trying to lower it down to 750 or so as recommended by Forte's FI guy and my cam (Ford E cam). I started at 800, then 700 target idle speed but it does not change the idle down at all. When I turn in the idle screw, the motor starts to stumble when letting off of the throttle and the motor is cold (my original problem that I fixed by adjusting the same screw).

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My TPS reads from 0% to 98% closed to WOT. My idle was at 950 and I dropped it to 850 and it still runs good and no issues with stumbling as I come to a stop. Lower than 850 probably isn't realistic for the Sniper based on everything I've read. To set the idle, first set your target in the handheld to what you want it to be. Then:

IDLE SETTING/THROTTLE PLATE SETTING
Once the engine is up to operating temperature (above 160° F), the idle speed can be set to what was configured in the Wizard.
To do this, open up the Initial Startup gauge screen. With the vehicle in neutral, adjust the idle screw until the IAC Position
reads between 2% and 10%. While adjusting the throttle plate screw, watch the TPS value and make sure it stays at 0%. While
adjusting the throttle plate screw, the TPS position may begin to read higher than 0%. If this happens cycling the ignition switch
will recalibrate the TPS back to zero.
NOTE: Do not attempt to set the target idle speed and IAC position until the engine is above 160°F!

Quote:

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Originally Posted by TMartinLVNV

I'm just starting to read up on all of the adjustments for the Sniper. My motor is running very well after I got the IAC adjusted correctly. I have almost 1000 miles on it. I hooked up the display controller and keyed on. The TPS reads 0% as it should. I depressed the pedal all the way to the floor and could only get 78% throttle. I then opened the throttle blades manually on the side of the throttle body and can get 79%. So I think that I have the pedal and cable adjusted correctly. In reading the Holley literature, I should be able to get 95-100% throttle at WOT.

What readings do you get at WOT? I'm thinking about calling Holley tomorrow morning to see if I can do anything else.

Also, my idle is right at 850-900. I was trying to lower it down to 750 or so as recommended by Forte's FI guy and my cam (Ford E cam). I started at 800, then 700 target idle speed but it does not change the idle down at all. When I turn in the idle screw, the motor starts to stumble when letting off of the throttle and the motor is cold (my original problem that I fixed by adjusting the same screw).

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I fixed the 78% max TPS problem. There was an interference problem on the throttle linkage with my cruise control hookup.

https://thefactoryfiveforum.com/show...l=1#post423396

I just got my Mk IV with BPE 347 Holly Sniper EFI out on the road this week. She's running great. Not much popping etc when I coast down a hill. However, I do have a an issue where the RPM will almost drop to zero and then recover when I push the clutch in when coasting up to a stop. This seems to be a common occurrence with Snipers and there are multiple threads on the Holly Forum for me to research, but just wondering if you also ran into this issue? If so, how did you solve it?
Thanks!

Quote:

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Originally Posted by Caddy Dad

I just got my Mk IV with BPE 347 Holly Sniper EFI out on the road this week. She's running great. Not much popping etc when I coast down a hill. However, I do have a an issue where the RPM will almost drop to zero and then recover when I push the clutch in when coasting up to a stop. This seems to be a common occurrence with Snipers and there are multiple threads on the Holly Forum for me to research, but just wondering if you also ran into this issue? If so, how did you solve it?
Thanks!

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So, the first question I'd ask is where you set your idle? If it's below ~850-900, you are going to have trouble. I haven't done any tuning of the idle circuit other than use the quick setup to set the desired idle speed and IAC screw.

Quote:

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Originally Posted by Papa

So, the first question I'd ask is where you set your idle? If it's below ~850-900, you are going to have trouble. I haven't done any tuning of the idle circuit other than use the quick setup to set the desired idle speed and IAC screw.

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I haven't adjusted the stock parameters that came with the engine when it was delivered. So the idle is set about 1000 RPM and I haven't touched the IAC screw. From what little I've read I'm thinking that maybe the idle ramp down time may need to be adjusted?

Thanks!

Quote:

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Originally Posted by Caddy Dad

I haven't adjusted the stock parameters that came with the engine when it was delivered. So the idle is set about 1000 RPM and I haven't touched the IAC screw. From what little I've read I'm thinking that maybe the idle ramp down time may need to be adjusted?

Thanks!

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I'd recommend first simply running through the quick setup for setting the idle and see where that gets you. I'd target ~900rpm to start.

IDLE SETTING/THROTTLE PLATE SETTING
Once the engine is up to operating temperature (above 160° F), the idle speed can be set to what was configured in the Wizard.
To do this, open up the Initial Startup gauge screen. With the vehicle in neutral, adjust the idle screw until the IAC Position
reads between 2% and 10%. While adjusting the throttle plate screw, watch the TPS value and make sure it stays at 0%. While
adjusting the throttle plate screw, the TPS position may begin to read higher than 0%. If this happens cycling the ignition switch
will recalibrate the TPS back to zero.
NOTE: Do not attempt to set the target idle speed and IAC position until the engine is above 160°F!