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BAKERrps13
08-25-2009, 08:50 PM
Hey guys, other than the MAFS, what else would cause my SR to run so rich it dies at idle?

After repairing a few issues with my redtop SR (all turbo gaskets, steering rack, BMC, fan controller, Z32 MAFS) my car now runs so rich it stalls after 10 seconds of idling. The car was running perfectly fine before I started this group of repairs.

Current Condition:
-Start the car (with some trouble), car starts to erratcally idle around 3-4k (MAFS unplugged) or erratically idle at 4-5k (Z32 or SR MAFS installed), then dies after 10 sec.
-Pulling the spark plugs shows they are covered in fuel along with some standing fuel on the pistons. All cylinders the same so no broken o-rings.
-SAFC was set correctly for each MAFS; 6in 6out for SR MAFS; 2in 6out for Z32MAFS; 4cyl arrow up to the right.

What I have checked:
-I spliced and soldered the SR MAFS harness back into the newly installed Z32 harness so that I could verify if the problem was a broken Z32 MAFS, but it had the same effect. SAFC was updated for either MAFS I put in.
-When the motor is off, SAFC shows sensor voltages to be in the 0.01V range and throttle at 0.4V. If I ground the input voltage, it reads 0V.
-No continuity between the wires in the MAFS harness (except for the ground wires of the Z32 harness)

My only thoughts on direction:
-It seems the MAFS are good, but it must be the problem - what else would cause it to spray so much fuel?

Thanks in advace for any help. James
S14_Kouki
08-25-2009, 09:55 PM
check your timing first then your car is prob flooded by now from u trying to start it and it running really rich so clean your plugs or replace them then you will have to crank the car with the no fuel to dry out the cylinders. But I think its prob your timing have u messed with that??
BAKERrps13
08-25-2009, 10:19 PM
check your timing first then your car is prob flooded by now from u trying to start it and it running really rich so clean your plugs or replace them then you will have to crank the car with the no fuel to dry out the cylinders. But I think its prob your timing have u messed with that??

I actually did not touch the timing, so it should be fine set like it was before. I would say that there is too much fuel for it to be the timing adjustment. And you are right, the cylinders were flooded and I had to dry the plugs and pistons.

I would like to say the problem is the MAFS sensor wire shorting to something but I think the voltages the SAFC is reading are in the right range?
BAKERrps13
08-26-2009, 05:35 PM
Does anyone have any other suggestions?
4x4le
08-26-2009, 08:34 PM
Take the safc out of the equation and test out the sr maf. Either way dont let the safc re enter the equation.
BAKERrps13
09-03-2009, 12:41 PM
Take the safc out of the equation and test out the sr maf. Either way dont let the safc re enter the equation.

I now have the SAFC bypassed but it didn't change anything. I did find that the coolant temperature sensor was disconnected from when I installed the DiF fan controller.

The car now will turn on but then die from excessive fuel. Revving the motor causes it to begin to misfire badly from too much fuel. What could cause the car to want to dump so much fuel? MAFS and coolant temp sensor maybe, but those seem to be working correctly. I also fixed a vaccuum leak in the intake manifold, but it didn't do much of anything.

If anyone has any suggestions, LMK. I will try to keep this thread updated if I can find a solution.
Touge180sx
09-03-2009, 01:02 PM
Fuel pressure?
Is it all cylinders or just 1? stuck injector/s?

Im not sure if it does this but if the safc is hooked up turn car to on position and check injector duty cycle on the safc, Make sure your wiring is ok

Also be careful, if its so much fuel its standing on the piston you probably have some getting in your oil, change your oil.