First start attempt - starts and dies instantly

[ben1272]

Now the fun begins.....I put 5 gallons of new fuel in (first fill), no leaks. Turned key, fuel pump turns on. Did this several times and listened as the pump loaded up. When it settled into a consistent whine I checked for fuel system leaks and found none. Then tried to start.

First attempt failed due to clutch switch that needs adjusting. I defeated the switch with my finger and she started very briefly and shut down right away. Exhaust smells good. Giving gas does not help it run any longer.

I attached my cheap OBDII scanner and it said no codes, which I dont believe as there is no downstream O2 sensor connected at all! I would have figured this would have thrown a code by itself, no?

Now scouring the web looking for insight, and posting for all you smart guys out there! I would love to hear your thoughts and appreciate them in advance!

On to my search.... and yes, I am keeping video footage of all my failures so far.... :mad:

-Ben

[ben1272]

I know this could probably be a hundred things, and I have not provided enough info. Car seemed to run well when I took her apart 1.5 years ago, so I am hoping the tune is not the problem, but I suppose it could be.

[ben1272]

Well, if I disconnect the MAF it starts and seems to run pretty well. Re-connect and starts but dies instantly. Tried flipping intake to reverse MAF direction, still no soap. New MAF doesnt fix problem either. Maybe I have a bad wire/pin on my connector? I have looked for any intake plumbing that looks like it could be leaking....all looks tight. Might have to pressurize it and gauge it.

Any other ideas? Maybe re-conditioned MAF is junk too? Should I try a new factory Denso MAF?

It runs nice without the MAF connected....hmmmf.

[07FIREBLADE]

Very possibly could be a bad pin in the maf sensor. I had your same problem and just going over the connector solved my problem.

[redfogo]

Have you tried connecting the green connectors? Normally this will tell you everything that's not connected.

[07FIREBLADE]

That's for reflashing your ecu. There test mode connectors. It doesn't have anything to do with what codes are being thrown. Maybe your tune got rid of the downstream codes. I know I don't throw a code and I don't have a downstream o2 sensor. My afr is in its place and my tuner used that for my tune.

[Sgt.Gator]

If the MAF is not reversed it's possibly (probably) a massive intake leak. The most likely places for it to be are the intake to turbo connection, on the bottom where it's hard to see/feel but will often slip off. Or the TMIC to Throttle body connector on either end. Check those three places first. If they feel ok do a smoke test.

[ben1272]

I'm going to make a smoke machine if I cant spot a leak under the TMIC. Thanks for the advice, keep it coming! I hope I dont have some sort of major problem to deal with.

[redfogo]

That's for reflashing your ecu. There test mode connectors. It doesn't have anything to do with what codes are being thrown. Maybe your tune got rid of the downstream codes. I know I don't throw a code and I don't have a downstream o2 sensor. My afr is in its place and my tuner used that for my tune.

Correct it is for reflashing it will also do a check on sensors and throw a temp cell if anything is unplugged. That's why your rad fans and other sensors start to click and turn on. It's doing a self check. Example mine always tells me my evap stuff is unplugged cause I deleted it even though I deleted the codes. This is just a temp diag mode. I use this to see if anything is unplugged or not showing up. Maybe I'm wrong idk but I have used them for this with my tactrix logging and it's helped me diag things.

Also when you reflash diag mode stops and reflash starts that's why the fans stop turning on and off it gets a write signal and goes into reflash mode.

[ben1272]

Alright, I think I have it fixed. I checked for leaks by taping openings off and blowing into hose connected to vacuum port and found none, just a his coming from exhaust near turbo, which I figured was normal. Put everything back together and decided it had to be wiring. Looked at MAF sensor and measured resistance between pins to find the pair that go to the IAT thermistor, which I figured must read in kOhms. Once I found these, compared to the two brown wires on the MAF connector going into the harness (the IAT leads).....THEY WERE ON WRONG SIDE OF THE CONNECTOR! Someone mis-wired my connector somewhere in its life and swapped pins 1 and 2 with 4 and 5. I put them back and started right up and assumed a nice idle shortly after of around 500-600 rpm. It is still hunting a bit, and now I have other things to look at, but it runs! It is a good feeling.

My OBDII scanner says IAT reading is -40F.....obviously not in my heated garage, so something is still wrong.....I hope the pins being reversed didnt fry something in the ECU. Car was operational when I bought it, so I dont understand what happened. Maybe it was disconnected and running in limp mode when I bought it.

CEL is on and codes are being thrown though I have not investigated them yet. At least one of them was evaporative emissions circuit related, which is mostly not present since I replaced it all with a charcoal canister. I may have to buy an accessport next....

I have an oil leak on my right side valve cover or under the belt cover.....drips right onto exhaust pipes below....smokey.

Temp came up, one fan came on, one came on and shut off immediately....dont know why. Radiator and its hoses never got even warm.

I plane to add more coolant once it cools down and start her up again for a second heat cycle. Might jack the front of the car up to, just to move air bubbles around. I was hoping the bleed line I added from top engine coolant pipe to header tank would purge air, but given no flow of coolant to radiator I assume something must be locking it up.

All and all a good day. Now if I can get oil leak squelched by tightening valve cover bolts 'll be a happy camper. I'm hoping idle will stop hunting and stabilize a bit more too as it runs some more....maybe it is learning? IAT reading -40F cant be helping.....

Thanks for the replies to my original post!

-Ben

[ben1272]

I put back in the OEM Denso MAF and the IAT codes disappeared leaving only my O2 codes and evaporative emissions codes. Car idled a bit better and seemed to rev smoother, but may have been my imagination.

[Sgt.Gator]

Swapped Pins! That's the kind of mod that will drive a new owner insane. I'm wondering if they got swapped and the weird IAT reading is because the car was converted to a speed density tune?
https://cobbtuning.atlassian.net/wiki/display/PRS/Subaru+Speed+Density+Guide%3A+2.5L

[ben1272]

It was converted to something at some point, as the MAF pin had been tapped into at the connector with a crimp fitting.

Now I am struggling to get the temps to be reasonable....at idle shoots up to 235 pretty quick and still dont feel much heat getting to the radiator. I have over 3 gallons of coolant in the system. I am starting to suspect thermostat and/or water pump.....ugh. I need to do clutch anyway, and right side valve cover is leaking some oil in a couple of places, so it looks like I have my work cut out for me. Still hoping cooling will resolve itself. Have been through approaching 10 heat cycles, which FFR says is totally normal in the manual.

[07FIREBLADE]

Probably speed density swap. They tapped into a few wires to get that thing running. Seen it multiple times while working on harness for customers at iwire.

[ben1272]

Maybe, but doesnt make sense to put the +V and GND on the IAT sensor.....I am lucky that something has not been wrecked! Still getting temps that are too high, but I finally have hot coolant reaching the radiator and it is taking much longer for temps to climb. I think I am heading in right direction!

[ben1272]

Kept starting adding coolant, reving, etc. I think I got it now and it seems to maintain 200-205 pretty consistently idling in my garage (41 degrees F today). I finally woke up and read some earlier threads that said not to remove radiator cap once you start bleeding air as it will introduce more air when removed. Should have only been using the turbo coolant reserve tank on top of engine. All is well now I think.

Thanks for replies and suggestions. I will post a video of this thing running....it has been 1.5 years and feels good. More work to do.....

[Wayne Presley]

Did you do this mod?
http://thefactoryfiveforum.com/showthread.php?18090-VCP-Cooling-System-Mod