Coyote Gen3 – Cranks but Won’t Start - Ignition Switch + Control Pack Troubleshooting

[aganjoo]

Hi all,

Apologies for the duplication for those of you who frequent ffcars.com and this forum — I’m cross-posting here in case someone has run into a similar issue and might have some additional insight.

I’m building a MK4 Roadster using a Gen 3 Coyote engine and the Ford Performance control pack, and I’m currently stuck trying to get the engine started.

Here’s the situation:


When I turn the key to ON, the gauges power up and the fuel pump primes briefly as expected.
When I turn the key to START, nothing happens — no crank.
I confirmed that the SMR wire shows 12V during the START position, and verified voltage at the pigtail.
If I remove the starter relay from the control pack and jump it manually, the engine does crank.


Based on feedback from other builders and Ford Performance, I tried using the jumper on the control pack method to crank the engine for long durations (around 40–45 seconds, multiple times), since I was told these engines may need extended cranking the first time to start. Unfortunately, it still cranks but does not start.

I’ve been pursuing this cranking workaround in parallel while trying to resolve what seems to be a wiring issue between the Ron Francis harness and the Ford Performance control pack that's preventing proper ignition switch function. I've also reached out to Ford Performance and am awaiting further guidance from their team.

As part of troubleshooting, I’ve reviewed multiple forum threads and followed much of the guidance posted by others with similar issues. The one thing I haven’t done yet is add additional grounding. I currently have a single ground strap connecting the engine to the chassis. Could lack of additional engine grounds be contributing to the no-start condition?

If anyone has suggestions for further troubleshooting steps—especially around the control pack, PCM signals, or grounding—I’d really appreciate the help.

Thanks in advance!

[David Ferguson]

Clutch Switch or Neutral Detect?

[edwardb]

The connections between the Ford Performance Coyote harness and the RF harness are quite simple. Sounds like you have them.

- Coyote Ignition Relay Trigger (light green) connected to any RF wire that's +12V at all times when the ignition key is on. Typically to the RF Orange EFI/Coil wire, although the choke wire works too. I've used both.

- Coyote Starter Motor Request (SMR) (light blue) to the RF blue start wire directly off the ignition switch. Must be +12V whenever the key is in the start position.

If those two are wired correctly and provide the voltages shown, the Coyote has what it needs. You mention hearing the fuel pump briefly cycle. That suggests the fuel pump is wired correctly and the Ignition Relay Trigger is waking up the system. At that point, you should also hear the throttle body cycle and pressing the accelerator pedal (DBW) you should hear the throttle body moving. That's further confirmation the system is alive and should be ready to start. There's really nothing else to add regarding the interface between the Coyote and the RF harness. Not sure that Ford Performance can add anything else. Maybe only confusion if they don't understand our setup. (It's happened with others I've helped...)

I don't necessarily recommend trying to jump the starter. If the PCM doesn't want to spin the starter there's a pretty good chance it's also not going to start the fuel pump or trigger the ignition. You may have seen where some have jumped the fuel pump (I've recommended it) because on a new installation it takes longer to achieve pressure in the lines, fuel rails, etc. plus gives a chance to check for leaks and set the regulator.

David Ferguson suggested the clutch neutral switch and that's the first place I'd look as well. Sorry for all the words before saying I agree. Just wanted to confirm the basic setup. I'm assuming you have the switch provided in the control pack on the clutch pedal box, the harness from the control pack plugged into it, and the switch properly adjusted so that it closes when the clutch is pushed down. Test it with a multimeter or whatever you have. The system will act exactly like you're describing (everything seems to be working but it won't crank) it that switch isn't closed.

Unlikely, but wouldn't hurt to scan the ODB2 port for any codes. If you have the control pack and engine properly grounded, wouldn't seem grounds are an issue, but wouldn't hurt to check again. I typically put two on the engine, but one should get you running. Note that Ford wants you to run the control pack ground directly to the battery. With the FF chassis that's not necessary, but the Ford Performance help desk may ask you to confirm how you have it wired.

[aganjoo]

David, Thanks for the note. I should have mentioned earlier that I alreday verified the clutch switch continuity and even even jumped it to doubly sure

[Erik W. Treves]

I would jump both the starter and the fuel pump and try -

once it starts I would investigate why the start circuit isn't turning the starter.

If you are getting the 12volts where you are suppose to on the control pack there is no reason the engine won't start.... I have documented in my last 2 coyote control packs installation I have had to jump the fuel pump every time on the first attempt.... not sure why that is...

[aganjoo]

The connections between the Ford Performance Coyote harness and the RF harness are quite simple. Sounds like you have them.

- Coyote Ignition Relay Trigger (light green) connected to any RF wire that's +12V at all times when the ignition key is on. Typically to the RF Orange EFI/Coil wire, although the choke wire works too. I've used both.

- Coyote Starter Motor Request (SMR) (light blue) to the RF blue start wire directly off the ignition switch. Must be +12V whenever the key is in the start position.

If those two are wired correctly and provide the voltages shown, the Coyote has what it needs. You mention hearing the fuel pump briefly cycle. That suggests the fuel pump is wired correctly and the Ignition Relay Trigger is waking up the system. At that point, you should also hear the throttle body cycle and pressing the accelerator pedal (DBW) you should hear the throttle body moving. That's further confirmation the system is alive and should be ready to start. There's really nothing else to add regarding the interface between the Coyote and the RF harness. Not sure that Ford Performance can add anything else. Maybe only confusion if they don't understand our setup. (It's happened with others I've helped...)

I don't necessarily recommend trying to jump the starter. If the PCM doesn't want to spin the starter there's a pretty good chance it's also not going to start the fuel pump or trigger the ignition. You may have seen where some have jumped the fuel pump (I've recommended it) because on a new installation it takes longer to achieve pressure in the lines, fuel rails, etc. plus gives a chance to check for leaks and set the regulator.

David Ferguson suggested the clutch neutral switch and that's the first place I'd look as well. Sorry for all the words before saying I agree. Just wanted to confirm the basic setup. I'm assuming you have the switch provided in the control pack on the clutch pedal box, the harness from the control pack plugged into it, and the switch properly adjusted so that it closes when the clutch is pushed down. Test it with a multimeter or whatever you have. The system will act exactly like you're describing (everything seems to be working but it won't crank) it that switch isn't closed.

Unlikely, but wouldn't hurt to scan the ODB2 port for any codes. If you have the control pack and engine properly grounded, wouldn't seem grounds are an issue, but wouldn't hurt to check again. I typically put two on the engine, but one should get you running. Note that Ford wants you to run the control pack ground directly to the battery. With the FF chassis that's not necessary, but the Ford Performance help desk may ask you to confirm how you have it wired.

Paul, Thanks for the detailed response. My comments below but happy to share any additional details

- I have verified the clutch safety setup and it is working as expected, even jumped it
- I do hear the throttle body cycle
- Regarding jumping from the fuel pump. I did jump that and it was continuously running while I was cranking the engine. I had jumped it previously to set the fuel pressure as well
- I connected to the ODB2 and read the codes and the only ones I got were for the missing VIN and oil pressure sensor. When I discussed these codes with Ford performance they mentioned that is because I was using the sender that came with the engine vs one that came with the control pack. However they confirmed that I can ignore those for now as they do not impact the engine start but recommended that I swap it out later
- I have the control pack ground wired to the chassis as you mentioned but just to eliminate any concerns ran an addition temporary ground wire from the control pack to the battery as well

I am pretty stumped right now;o)

Thanks
Amit

[aganjoo]

I would jump both the starter and the fuel pump and try -

once it starts I would investigate why the start circuit isn't turning the starter.

If you are getting the 12volts where you are suppose to on the control pack there is no reason the engine won't start.... I have documented in my last 2 coyote control packs installation I have had to jump the fuel pump every time on the first attempt.... not sure why that is...

Erik, I jumped the fuel pump but no joy

[nuhale]

Couple of builds as I too have had a few run ins with coyotes. I would go through the grounds with a continuity tester as I had a eyelet terminal snap in the shrink sleeve on one of the grounds in the clutch safety and wasn't grounded. Make sure ALL grounds on the control pack are grounded.

Kinda simple but fuses and relays in the PCB. Go through one by one with a continuity tester and make sure you don't have any burnt fuses.

One other area to look at is the crank tone ring and sensor out of where the bell housing meets the engine. Did you build the engine? Was this installed correctly? My current coupe build wasn't firing and had same symptoms you describe. Turned out that my crank shaft position sensor was a cheap piece of $%&T and once swapped out with a new one it fired right up. That sensor with the tone ring is what sends the signal to fire the coils.

Are you getting fuel? With all the cranking you should be able to smell fuel from the exhaust. You can check this with a NOID light to see if your injectors are firing.

I'm betting its one of these things!

[aganjoo]

Couple of builds as I too have had a few run ins with coyotes. I would go through the grounds with a continuity tester as I had a eyelet terminal snap in the shrink sleeve on one of the grounds in the clutch safety and wasn't grounded. Make sure ALL grounds on the control pack are grounded.

Kinda simple but fuses and relays in the PCB. Go through one by one with a continuity tester and make sure you don't have any burnt fuses.

One other area to look at is the crank tone ring and sensor out of where the bell housing meets the engine. Did you build the engine? Was this installed correctly? My current coupe build wasn't firing and had same symptoms you describe. Turned out that my crank shaft position sensor was a cheap piece of $%&T and once swapped out with a new one it fired right up. That sensor with the tone ring is what sends the signal to fire the coils.

Are you getting fuel? With all the cranking you should be able to smell fuel from the exhaust. You can check this with a NOID light to see if your injectors are firing.

I'm betting its one of these things!


Thanks for the suggestions. I will try these steps and report back

I can smell the fuel for sure and I can hear the injectors coming on when I jump the fuel pump.

[BEAR-AvHistory]

Did you check the wiring to the ignition switch. One position off & the car will not run. A friend told me.:rolleyes:

[aganjoo]

Did you check the wiring to the ignition switch. One position off & the car will not run. A friend told me.:rolleyes:

Thanks Kevin, I did check it but never hurts to check again so will do so again this evening

[MaxVmo]

Inertia switch is correct? I suppose the fuel pump might not run with it tripped…. I had a similar issue where it would crank but didn’t start, turns out it was a coil wire I had missed. Maybe that’s not how your setup works on a Coyote.

[aganjoo]

Hi everyone,

Thanks again for all the guidance so far — several of you suggested checking the inertia switch, clutch safety, and other items, so I wanted to provide an update after more investigation and testing this evening.

It appears I may be dealing with a grounding issue that is preventing the relays from getting the ground signal they need, which in turn is keeping the fuel pump from running.

A few key findings from tonight’s troubleshooting:

The inertia switch and clutch safety circuit both check out fine — I ran continuity tests on both and confirmed proper operation.

Earlier, I thought I was hearing the fuel pump when turning the ignition key to START — turns out that sound was just the throttle body cycling.

The fuel pump only comes on if I jump it directly at the PCM.

I checked all fuses in the PCM, all relays on the Coyote PCM, and the Ron Francis harness. Everything checked out fine.

I confirmed I have 12V on the trigger and SMR wires at the correct times, but the fuel pump relay is not being triggered.

With the fan off in the garage today, I noticed for the first time a hum in the fuel pump relay on the Coyote PCM while the key is in start/run position. I bench-tested the relay itself, and it works fine — so it seems something in the circuit may be causing the hum.


As part of chasing down the grounding issue, I have;

Installed a new ground from the PCM directly to the battery.

Tomorrow morning, I’ll be adding a new ground for the Ron Francis harness as well.


Possible Next Steps

Could a poor or floating ground cause the fuel pump relay to hum and fail to trigger?

Are there known PCM grounding points (in addition to battery and chassis) that must be connected for the Gen 3 Coyote control pack to function correctly?

Any specific wiring or continuity checks between the PCM and the fuel pump relay ground path I should focus on?

Has anyone seen a fuel pump relay hum like this due to backfeeding or partial grounding?

Thanks for the continues support and guidance

[Erik W. Treves]

I don't understand how you have the fuel pump not running issue if you jumped the relay and you said it worked? but are you saying that you lose 12volts while it is cranking then?

"The fuel pump only comes on if I jump it directly at the PCM." -- leave it that way and get the engine running - so it's steady on.... do not remove it on the initial cranks.

did you do this>>>?

[aganjoo]

Hi Erik, my apologies. I don’t think I did a good job explaining in my last message late at night.

If I jump at the relay at the PCM, the fuel pump runs fine. What I was trying to do is figure out why cranking isn’t working from the ignition switch so I plugged the relays back in to the PCM and tried to crank using the ignition switch. That is when I noticed a continuous Hum from the fuel pump relay on the PCM.

I’m trying to go step-by-step right from the Ron Francis harness all the way to the PCM to figure things out. As a sidenote, Ford Performance did tell me that I can probably squirt some starting fluid into the engine before cranking to try if that works when I’m doing everything directly at the PCM by jumping and skipping the ignition switch completely.

I haven’t tried that yet

[rich grsc]

I can probably squirt some starting fluid into the engine

​Don't. If you have never used starting fluid, it's a good way to damage your engine

[Papa t]

I had a similar issue with my coyote. I could hear the fuel pump run but I was getting no fuel pressure. My issue was a bad fuel pump.

[kirby]

I can probably squirt some starting fluid into the engine

​Don't. If you have never used starting fluid, it's a good way to damage your engine

Starting fluid has its place and I tend to agree with avoiding it. However you can take a little bit of gasoline in a spray bottle and and mist it into carbs, intakes, etc and it works pretty well. I have never done this on my coyote but have used this to verify if an engine would fire.

[Erik W. Treves]

Hi Erik, my apologies. I don’t think I did a good job explaining in my last message late at night.

If I jump at the relay at the PCM, the fuel pump runs fine. What I was trying to do is figure out why cranking isn’t working from the ignition switch so I plugged the relays back in to the PCM and tried to crank using the ignition switch. That is when I noticed a continuous Hum from the fuel pump relay on the PCM.

I’m trying to go step-by-step right from the Ron Francis harness all the way to the PCM to figure things out. As a sidenote, Ford Performance did tell me that I can probably squirt some starting fluid into the engine before cranking to try if that works when I’m doing everything directly at the PCM by jumping and skipping the ignition switch completely.

I haven’t tried that yet

Right.... if you look at my initial post... I have had this happen twice in a row now.... the PCM seems like it needs to see the engine running once before it will work...

The fuel pump doesn't run while initial crank.. thats what the first pulse is for... you need to leave the fuel pump relay bypassed ... crank the engine....let it fire and run for a second or 2.... then put the relay back in ... and it should be fine after that..... assuming everything else is wired correctly.....

[nashuanuke]

The connections between the Ford Performance Coyote harness and the RF harness are quite simple. Sounds like you have them.

- Coyote Ignition Relay Trigger (light green) connected to any RF wire that's +12V at all times when the ignition key is on. Typically to the RF Orange EFI/Coil wire, although the choke wire works too. I've used both.

- Coyote Starter Motor Request (SMR) (light blue) to the RF blue start wire directly off the ignition switch. Must be +12V whenever the key is in the start position.

If those two are wired correctly and provide the voltages shown, the Coyote has what it needs. You mention hearing the fuel pump briefly cycle. That suggests the fuel pump is wired correctly and the Ignition Relay Trigger is waking up the system. At that point, you should also hear the throttle body cycle and pressing the accelerator pedal (DBW) you should hear the throttle body moving. That's further confirmation the system is alive and should be ready to start. There's really nothing else to add regarding the interface between the Coyote and the RF harness. Not sure that Ford Performance can add anything else. Maybe only confusion if they don't understand our setup. (It's happened with others I've helped...)

I don't necessarily recommend trying to jump the starter. If the PCM doesn't want to spin the starter there's a pretty good chance it's also not going to start the fuel pump or trigger the ignition. You may have seen where some have jumped the fuel pump (I've recommended it) because on a new installation it takes longer to achieve pressure in the lines, fuel rails, etc. plus gives a chance to check for leaks and set the regulator.

David Ferguson suggested the clutch neutral switch and that's the first place I'd look as well. Sorry for all the words before saying I agree. Just wanted to confirm the basic setup. I'm assuming you have the switch provided in the control pack on the clutch pedal box, the harness from the control pack plugged into it, and the switch properly adjusted so that it closes when the clutch is pushed down. Test it with a multimeter or whatever you have. The system will act exactly like you're describing (everything seems to be working but it won't crank) it that switch isn't closed.

Unlikely, but wouldn't hurt to scan the ODB2 port for any codes. If you have the control pack and engine properly grounded, wouldn't seem grounds are an issue, but wouldn't hurt to check again. I typically put two on the engine, but one should get you running. Note that Ford wants you to run the control pack ground directly to the battery. With the FF chassis that's not necessary, but the Ford Performance help desk may ask you to confirm how you have it wired.

Try this, I stupidly used a weatherpack here and one of these wires pulled loose, it's such a little thing, tucked up under the dash that will ruin your day. Luckily I found it after only a couple of hours of random troubleshooting. Those wires are now crimped and shrunk tight, there's no need to disconnect them anyways.

[FFinisher]

Was this resolved then?

[aganjoo]

Hi all,

Apologies for the delay in updating — after my last post I was in troubleshooting mode and waiting for Ford Performance to get back to me. I wanted to share the full resolution and a couple of related discoveries in case it helps anyone else down the line.

Summary of the Fix

After eliminating all the usual suspects (fuses, relays, wiring between the Ron Francis harness and the Ford Performance control pack, grounds, inertia switch, clutch safety, etc.), I had a detailed discussion with Ford Performance. Based on the symptoms, they suspected the PCM itself.

They shipped me a replacement PCM with fresh firmware, and as soon as I plugged it in the car started immediately — within 3 seconds — straight from the ignition key.

No jumping relays, no extended cranking. The fuel pump primed as it should, the engine fired right up, and after a few minutes everything settled down normally (RPM, oil pressure, etc.).

Ford Performance confirmed that some PCMs ship with corrupt firmware. If you’ve gone through all the other checks and still can’t get the car to start, it’s worth reaching out to them.

Key Observations Before Resolution

Key ON: gauges lit, throttle body cycled, but fuel pump wasn’t actually running.

Key START: relays had power but were not being grounded, so no crank from ignition.

Only way to crank/run fuel pump was to jump relays directly at the control pack.

Verified every fuse and relay, checked harness wiring (SMR and trigger wires had 12V at the right times), and added dedicated battery grounds.

Inertia switch and clutch safety both checked out fine.

OBD-II showed oil pressure error codes, which Ford Performance confirmed were just due to a sensor mismatch and not start-blocking.

Tried long cranking (40–45 sec) per Ford/Factory Five’s guidance for first starts, but still no luck.

Resolution

Installed replacement PCM from Ford Performance.

Engine started right away from the ignition key, as designed.

Fuel pump now primes on key ON, relays trigger properly, and starting behavior is normal.

Additional Note – Power Steering Issue

Once the engine was running, I discovered a violent steering shake caused by a power steering fluid leak.

After some troubleshooting and a chat with Michael Everson, I realized I had reversed the two hoses (return vs. pump). Once swapped to the correct ports, the steering system worked perfectly.

Hope this helps someone else who runs into the same frustrating issue.

PS: here is the first start video as well. You can hear my wife go "Oh God" when the coyote comes to life as it was so loud ;o)

https://youtu.be/qGsFkAhgP_Y

[kirby]

Yes!!! Congratulations!!

[Nigel Allen]

Great result on the engine.

[danmas]

Congratulations!

[Blitzboy54]

Been there my friend. Huge relief to get it resolved.