o2 Issues/Bumpy Idle/SES Light/ Im out of ideas...

[98GTcoupe]

Hey All,
Well i keep having a rough idle/WOT surging/SES light on all the time my idle smooths out with the A/C on. So, ive replaced the IAC, IAT, TPS, REAR 02Sim and Low coolant sensor and cleaned the throttle body an MAF sensor. So, I replaced the front bank number 1 o2 Sensor with a Bosch. The reasonin was i put a random Tech 3in-2.5 catless DP in. So I figured i would put in a new O2 sensor cuz I have 103k on her. Well, a week later i get an SES light, an the car hesitates and surges at WOT. The code is for the Front Bank 02 sensor i just put in. The car acts like this, WOT.... wait ok 2k, wait 3k wait 4k ooh ok now 5k an so fourth. Well, ive also replaced the plugs with Autolite 605's gapped at .55ths and put on new Accel wires. Also, i have 1 orginal coil pack and 2 new ones.
Any ideas? Fuel Injectors? Map sensor? Knock sensor? I dont have many left to replace. Also i have taped up my Vac lines. Maybe i have a vac leak. I cant find it.
Well Any help would be GreAT!!
THAnks


Greg

[johnnyr]

Have you replaced the mass airflow snsor? My daughters 02 Regal LS was throw a P0172 code & it was the mass Air flow sensor.

[BillBoost37]

What is the actual code?

Many times you can get a car scanned and be told "it's an o2 code" when it's no where near the truth.

[98GTcoupe]

So I scanned my car today with an AutoTap.
At WOT I saw 7.4* of Knock. (yikes)
Map Pressure at Idle. 11.5Hg
IAC Position at Idle 36 Counts.
2-6 Misfires.
Codes.
P0133-H02S Slow Response Bank 1 Sensor 1
P1107 Map Sensor Circuit Intermittent Low Voltage.
When the idleing began to get a lil bumpy, my Timing advanced from 17-20.
Ran misfire checks an saw nothing. But the counter said from 2-6 misfires.
Any Ideas?

[BillBoost37]

Check the O2 wiring for any plug wires touching it. If there are none, I'd suggest looking up the diagnostic aids from the FSM regarding the code and see if it is ever related to the MAF code you have. If not replacing the O2 as it's giving a slow response seems like the right route.

Check the wiring and maf. Try cleaning it with MAF specific cleaner. If that doesn't help, check the fsm diagnostic aids again. Unplugging the maf will default the airflow to table data instead of actual reading. If this makes the car run better the maf is usually bad.

[98GTcoupe]

OK
Well, Tonite i disconnected the MAF an it wouldnt start. So, i started it an let it warm up. Then disconnected it an it did idle a bit better with it off untill i gave it some gas. Then it ran like crap an got better with it off. I plugged it in an she started to idle a little worse. Hard to really notice. So, I also checked out the Map sensor wires an found a loose wire. Re wired it an the low voltage went away from the Map sensor. Also i tried another Map sensor as well. Same results. All the While ive been scanning with an AutoTap. I cleared the Map sensor an rescanned. It never came back up an i re scanned 3 more times. So i still got the 02 Issues. So i changed out the O2 sensor with a junk yard one and got a new code. H02S Circuit Insufficent Bank 1 Sensor 1. WHat the hell. An the cars idle will be smooth then vary from 670ish-720ish an maintain 7ish for awhile then bump back down. My MAF rate at idle goes anywhere between .5-.6 lb/min. So, maybe i have a bad o2 wire on the harness?
Any ideas?
Thanks
Greg

[BillBoost37]

Sounds like that O2 sensor is junk. Insufficient means it's not really working. The old one may be bad, but the new one is worse.

[98GTcoupe]

Ok well thats just crazy. Its a bosch. Well i got the warrenty on it so ill take it back an get another one. But do you think my car is eating them up? Or is it the gas i run. I only run 93 ever.

Oh an i heard that when your IAC count is below 40 or so its a vac leak. Is that right?

[johnnyr]

Try a AC Delco 02 sensor they are better than Bosch. They are made for our cars, they cost a little more but you end up saving time & money using orginal GM parts when ever you can.