Running PIG rich

[eric_t12]

I haven't been on in a while, sorry for the seemingly difficult first post but here it goes anyway.

I've been away from the Shelby Z for about 5 years now, off and on, from the military and haven't had time to work on it myself.

A year or two ago the turbo went out, and my father and brother replaced it, they THINK they test drove it and that it ran fine but they aren't sure...

i get back the car is running PIG RICH! it appears to be just dumping fuel into the intake, because smoke is pouring out of the exhaust.


THings i've noticed.

It will run fine at idle, for the first few seconds of a cold start, as it warms, the idle becomes progressively worse, and the throttle response becomes progressively more horrible with stumbling/smoking.

Its throwing the 26 and 31 codes, but since both solenoids are disconnected, and the car previously ran fine without them, i suspect this isn't the culprit. before i replaced the other sensors (and subsequently disconnected the battery to clear the faults) it was throwing a O2 sensor code, but its not anymore...

...plus i've never seena bad O2 throw that much gas in anything.

its smoking moderately under the hood, as well. not sure if its seeping out of the exhaust or manifolds, or its simply oil burning off the head from valvecover seep, but it doesn't look like Oil smoke...?

Compression is = 94/101/100/100

Things i've replaced.

5 year old gas, with fresh 91.

Camshaft (to factory)

Plug wires (to lifetime warranty ones, after that it ran fine for a half hour, til the next day)

MAP Sensor (to factory, had a backfire and blew the last one)

TPS (threw a TPS code, replaced and code is gone)

Fuel Injectors (to factory, from S60, yea i know i thought that was it too)

Cleaned throttle body out completely with Carb Cleaner.

cleaned the plugs after every other attempt at fixing it.

we put 3" exhaust on it too, but i dont think that would have changed anything like that.

my thoughts


FPR stuck shut? will be checking fuel pressure later today.

Bad intake/exh gasket? dont know why it would be that, but i suppose its an option.

Weak coil? how can i check it?

Compression is solid. 94/101/100/100

HELP!

eric_t12@hotmail.com

[detobias]

Quote:

Originally Posted by eric_t12 It will run fine at idle, for the first few seconds of a cold start, as it warms, the idle becomes progressively worse, and the throttle response becomes progressively more horrible with stumbling/smoking. Compression is solid. 94/101/100/100

this describes the ECU coming off "open loop" into "closed loop"

i.e. the ECU is going from fixed tables of fuel flow and starting to sample the sensors, and allow the fuel to be modified - i.e. "closed loop"

it will be looking at O2 sensor, MAP, TPS, coolant temp, CAT (if TII), etc

my guess is MAP - make sure you have vacuum to it

I highly recommend this book for TDers
Amazon.com: How to Tune & Modify Chrysler Fuel Injection (Powerpro): Ben Watson: Books

in the meantime - try knizels fwd resource site
MiniMopar Resources

PS that compression isnt too great (altho it is consistent); R U at altitude? did you test all 4 plugs out; HEP unplugged; TB wired open ?

if so, try adding a tablespoon oil to each cylinder and see if psi comes up - if it does , usually = bad rings

[eric_t12]

Initially i thought it was closed/open loop as well, and i haven't confirmed it since my friend with a scanner now lives about 1 hour away...

its only running semi-smooth for 1-5 seconds on a COMPLETELY cold start.



What is the CAT? i've never heard of that one before... MAP/TPS have been replaced, and the map gets its own vacuum source, so i know its getting it, because when i bypass its solenoid the code for it trips.

I am still going to get the scanner from my friend asap.



AFA compression testing, no, we only did one plug at a time, with the throttle-body closed. HEP was hooked up, i didnt think that would make a difference, because the fuel injectors were disconnected.

I'm in South Dakota... eastern side, altitude unknown. its pretty flat here.

[puppet]

Forget about the compression for a minute. You have a fueling issue to tackle first.
Why did you have +40's in there to begin with? Was/Is the ecu set up for 3BAR action?
When you changed the injectors did you look over the wiring harness and connections to the injectors ... is the fuel rail GND in place?

[tryingbe]

Super60 injectors aka +40% injectors = 52lbs injectors.
Stock injectors = 33lbs injectors.

[eric_t12]

fuel rail ground in place, has been.

it HAD a 3 bar MAP before it backfired and blew it, its factory now.


when i first had it in it ran fine.

[EvilcowRoland]

Code 26 - fuel injector driver circuit open or shorted. Fault Code 26

The injector harness wires get brittle with age and the insulation breaks off creating shorts all over the place. Pull the harness and inspect/repair your wiring.

Also, CAT = charge air temperature sensor. On a T2 car, it's the sensor in the middle of the intake. Tells the computer the temp of the incoming air.

[puppet]

Quote:

Originally Posted by eric_t12 fuel rail ground in place, has been. it HAD a 3 bar MAP before it backfired and blew it, its factory now. when i first had it in it ran fine.

So ... the ECU is 2BAR or 3BAR?
.... starting to feel like a dentist here.

[tryingbe]

Put the STOCK injectors, STOCK ECU, STOCK 2 bar map sensor in the car and it'll probably runs fine.

Using SUPER 60 ECU, STOCK 2 bar map, and +40% injectors is asking how to blow your engine.

[eric_t12]

tryingbe - blow your engine with too much fuel?

and no, its all back factory, still smoking and stumbling like crazy.


puppet - ECU is factory. so is everything else electronic, now.

calm down, dentistry is hard, but its nothing to bash your head into a brick wall over.

Note: it DID run fine with all these things together for the two weeks i was home on leave and first added them all. it wasn't until the turbo blew and it was repaired that it started having all these problems, even then it was supposedly running good after the initial repair.

-----

Note 2: tested fuel pressure today, 20 with key off , but on at idle it was at 50 steady. still smoking and stumbling like crazy.

the car sat the whole 5 years i was in the army, including after the turbo reinstall.

ETA: the problems just popped up, apparently, within the few months from the repair to when i finally got back out ofthe Army.

[xdig]

Quote:

Originally Posted by EvilcowRoland Code 26 - fuel injector driver circuit open or shorted. Fault Code 26 The injector harness wires get brittle with age and the insulation breaks off creating shorts all over the place. Pull the harness and inspect/repair your wiring. Also, CAT = charge air temperature sensor. On a T2 car, it's the sensor in the middle of the intake. Tells the computer the temp of the incoming air.

+1

[eric_t12]

Whoa, my bad, mistake correction -


Code 36, is the second code its giving. Wastegate and Evaporator purge codes.

[EvilcowRoland]

Okay, well see that's different.

Pull the vacuum line to the FPR and see if it has gas in it. Leaky FPR can cause overfueling.

Edit: I thought unplugging the wastegate solenoid would put the computer in limp mode, but the minimopar site says no. I doubt limp mode would cause that much overfueling anyways, so nevermind.

[The Pope]

the computer uses the "rest" of the sensors when it is ice cold. There is one sensor it uses that needs to warm up, the 02. The 02 sensors can get stuck in rich or lean mode. The car starts ice cold and runs fine, because the injectors and everything else is functioning right. Then the 02 warms up and dumps a super lean signal into the computer, stuck in lean mode and out pumps the black smoke.

Go thorugh the old "shock the 02" procedure and see if it changes it. If not buy a new sensor or even better a nice new wideband.

[eric_t12]

Quote:

Originally Posted by EvilcowRoland Pull the vacuum line to the FPR and see if it has gas in it. Leaky FPR can cause overfueling.

i've pulled the line, and it didn't drop the pressure at all. not one bit. stayed at a steady ~50psi.

MiniMopar resources says that's actually slightly low... another idea trashed...?