i have been having probs with my car ever since the cat went south on me. put a pipe in its place. the idle is HORRIBLE!! it cuts out at low rpm's (2000rpm) and less. stumbles etc etc etc.... i hooked it up to a snap-on scanner today after work and here are the results.

NO trouble codes
when it goes into CLOSED LOOP, thats when the car really acts up
Battery 13.8- 14.0v
Fuel Pump 13.6v
Block Learn 108-121
IAC seems good in open loop, but varies from 78-160 counts in closed loop
TPS .58 - 4.58 at WOT
Exhaust Oxygen RICH
o2 ready - yes
o2 cross counts- 1
Base PW (ms) varies from 0.8 - 5.8 depending on accelleration
MAT 44 degrees celsius
MAF (gm/sec) 7 Airflow (gm/sec) 7 (stays within 2 of each other)
spark Advance 9-10 degress at a decent idle
coolant 82 degrees celsius
MAF burnoff OFF
KNOCK at about 4000rpm 3 degree
EGR 0% at idle 90-100% under throttle
EGR Diag SW - ON
o2 (mv) 850+ in closed loop and 600-700 in open loop

the car stalled with the iac count at 160
in open loop it is between 25-35

i really dont know what most of this means, thats why i posted it. i drive the car everyday to work and back (7 miles) and it is really bothering me. i am going to check FP and injector resistance tommorow after work. i am really thinking about swapping a carb on my car. it is really driving me NUTS!!!! ANY help would be greatly appreciated. thanks

 

Sounds rich to me. The O² agrees, and IAC seems to be reacting as well. Are your injectors leaking? Regulator leaking through the vacuum line?

 

how do i check the injectors and regulator for leaks?

 

try disconnecting the vac. line to the egr valve
mike

 

what would that do? btw i forgot to mention, when i put the car into fuel backup mode, it says it goes into "limp home mode", i could here something arcing around the injectors somewhere, like something was shorting out or something. i couldnt get it to do it evertime and it hasnt done it unless that mode was enabled. i couldnt see any sparks or smoke or any type of burnt wires on anything. i am curious to what exaclty happens when it goes into that mode. motor is off, key is on, and the fan comes on with that mode and the field service mode. thanks

 

ttt

 

Forget about forcing modes, and let the ECM do it's thing. If you force Backup Fuel and Spark mode, all that you're doing is retarding spark and adding even more fuel.

Since the situation sounds like it is already running rich, it doesn't need any more help. Check/change the oxygen sensor.

 

ok, i will change the o2 sensor tommorow and let you know if it helps. thanks man, i really appreciate it!

 

changed the o2 sensor today after work, drivability changed 100%, no more bucking when the car goes into closed loop. i actually thought the car stalled when i stopped at red and the tach wasnt jumping all over the place. the car runs alot better, lets just hope it stays that way. i have another question for you though, i checked the fuel pressure to day also. 37-39 at idle with vacuum attached and 45 with vacuum removed. the prob is, when i turn the car on and the fuel rail primes, it only goes to like 15 and then back to 0. tried double priming it and went to about 30 and then dropped to 0 instantly. after i shut the car off after it is running, the pressure drops to 0 immediately!! what would cause the rail not to hold pressure? thanks again vader, i was about to put a carb on my car beacause i was getting so sick of it bucking and not idleing. i am going to borrow my buddies scanner again and get some readings now since the car will actually idle pretty well. thanks

:hail: