playa7970

ok i got the backfire issue out of my hands finally... seemed to be a faulty TPS so now i have this really bad stumble issue which seems me that the car is running really rich to the point wre it stumbles throughout the whole rpm band, so i stopped driving the car its been like a week and a half and heres what iv replaced soo far... IAC, TPS, MAP, ICM, COIL, IAT i mean everything on this car is new except O2 sensors, and MAF i even took the advice and readjusted my valves to zero lash and then a 3/8 turn the pushrods arent tight and there is no up and down movement between rocker and pushrod and the pushrods are able to spin but not freely

so i finally said screw it and bought a OBD1 cable hook up for my laptop so im able to scan my car for codes and LT1-EDIT but im not even going to attempt to mess with the programming just yet so i scanned the car for codes and these where the results....

*MAP (Voltage Too High)
*Right O2 Sensor too lean (which when i scanned it with car running and it stayed at 4mv the whole time during my test drive)

These were my readings (Left to Right) at 3500 Rpm
MAP Kpa ...............94.5
LTERM COUNTS...............128......160
STERM COUNTS...............128......128
BPW mS ...............14.66...18.28
INJ DC ...............43.4.....54.1
O2 Mv ..............906.......4
AFGS ..............192.48

Any ideas sorry for the story im just out of ideas thanks !!!

playa7970

Anyone?

96flame

Unplug the O2 and see if it reads 450mv. With it reading full lean its dumping fuel in and flooding that bank of cylinders. Looks like you have a faulty O2 sensor. The MAP problem could be caused by the poor running.

playa7970

hmmm really so a faulty O2 sensor can cause one side too run rich huh thanks for the info

playa7970

also if this car had a vacuum leak wouldnt it run like crap all the time?? when i unplugged my battery to do my valve adjustment and plugged it back in the car ran smooth for 5 min them bam... back to stumbling-hesitation and would a bad o2 sensor really have such a affect on my car

96flame

Yes the long term fuel # being at 160 means the computer is adding alot of extra fuel. You may also need to replace the spark plugs on that bank if they've been fouled that bad. By removing the battery cable it cleared the fuel trim #'s from the computer thats why it was better for a bit.

playa7970

Well i just bought the sensor hope this works and ideas injuneer?

TobyZ28

Sounds like it was running "ok" because the car was in open loop since it was cold. Once it warmed up, it started using the O2's in closed loop and thus got thrown out of wack.

Sparkz28ss

change the o2

BlackScreaminMachine

I know tuner cat software, bearing everything is mechanically perfect, no leaks no other BS, look at your PE tables, see how much is being added

playa7970

Yesssss!!! i replaced the o2 and cars back up and running!! its not running as rich as it did the only thing is that the car is still somewhat backfiring out of the hole i have my datamaster log file if anyone can read it and tell me whats going on thanks alot for the help so far