Lee Kelsoe

hasn't anyone had this situation happen? I have since replaced both temp sensors and did a driveability test with it running good and disconnecting and capping off the egr vac line and it didn't change behaviour... I have cleaned the IAC and MAF AGAIN... as well as the IAT... (it was a little dirty) I also ran a full can of Sea Foam... (the kind you spray directly into the intake)...also noticed that it gets worse and goes bad quicker the closer I get the timing back to stock(10 BTDC) but at WOT it clears up... I pulled codes and got all pass yesterday, now today with KOEO I get 113 and with KOER I got 314 and 311(but I have bypassed the smog due to off road H pipe)... one thing that seems strange is (and maybe I'm just not doing it right) but from what I understand, you have 2 minutes to WOT after the KOER test ends to initiate the cylinder test... every time I try it, it immediately gives me a 538 saying it didn't receive the goose test.. does that mean my problems could be TPS related or IAT killing my short term fuel trims?... Help US!!

duncan01

Check your tps. setting it should be close to .90-.98 volts Key on Engine Off. You said your fuel pump bleads off fast, which is not supposed to happen. That make me think theres a hole in the rubber hose that connects the pump to the hanger assembly (know this from experience). I wouldnt run it much till you get that figured out. (Mine ran lean and poof!) Once the key is on and the system is primed it should bleed off over the course of a few hours.

Good luck

TrimDrip

Does it do it when the car is cold or does it have to warm up under the hood first?

Lee Kelsoe

not sure how warm it is under the hood when it starts.. I know it only takes about 3-5 minutes of driving it either highway or street... but turning the engine off and directly back on again fixes it for approximately the same period of time...
I just replaced the dizzy and nothing has changed... also, without having a fuel pressure tester, I did a little experiment and I did notice that it is priming(squirted good when tapping the schrader valve but not sure if it was 20+lbs. of pressure) and has some pressure while the engine is running(again by tapping the schrader valve), but almost immediately after turning the engine off, almost zero pressure from the schrader valve.. barely even welled up enough fuel in the valve tube to spill out... hole in the system or stuck open(bad) injector?

jam23r1

jumping in this is happing to me too just when I wot.

TrimDrip

I had a friend with a trans-am that had a fuel pump work part of the time. One day he could punch it and it would scald the tires, the next it would fall on its face. His symptoms when running bad are worse than yours. I ain't saying it isn't the pump, his car just ran worse than a buck.....do you have you wires separated? I have seen this cause spark to Jump in the distributor and cause a miss someone would have a hell of a time figuring out. I believe 1,3 and 6,5 wires need to be as far as possible away from each other.....is the car a 95?

Lee Kelsoe

I actually seen the wire separation thread and did made sure of that as well.. this started before I replaced ... plugs, wires, distributor, coil, both temp sensors, cap and rotor, fuel filter, O2 sensors, and IAT sensor...

TrimDrip

You can pretty much look at a maf and tell if it is dirty. If you want to test it, take something like a heat gun or hair dryer and heat up the electronics while the car is cold. If it acts up when u crank it, that is prolly it. This is an obd2 car right? Reason I ask is there is no plug under the dash for diagnostics on obd1 cars

Lee Kelsoe

well the MAF is clean as a whistle.... if I unplug it, it really runs like crap and the CEL lights up.. and '95 and below 5.0s are OBDI... I think only the V-6 got OBDII before '96...

BabyGT

94 up actually have an obdII plug under the dash, but 94-95 GT's it's not connected to the computer. 94 up v6 it's functional.