alright well i have been having a problem where my car isn't idling right or running right at all... i had a code thrown for my opti basically so i replaced the opti and it didn't help, but one of the rotor screws were backed out and laying in the cap so it didn't hurt to replace it anyway.... but anyway, we also tested the coil, which said it was bad, so replaced it... didn't help.... tested the ICM and it was fine... so today i had an appointment with the local gm dealership and the guy that worked there told me that he tested basically everything and nothing showed up messed up from what he could tell except that it seemed like the car was running rich and the computer was telling it it was running lean so it would bump up the fuel even more and it was basically flooding itself out.... and he said he tested the FPR and it was fine, tested the injectors and they were fine, all the temp sensors were good, and he started tellin me how i need a converter on it and i think he got confused about the o2 sensors cuz he was tellin me about how not having a converter will mess up my back o2 sensors, but i told him i didnt have them and he still seemed puzzled... but i don't know what to go to next... he said compression was fine and he didnt think it was anything broken down internally and he said next thing to try was changing plugs and o2 sensors.... anyone have any idea after reading all that garbage? lol

 

Hook up a vacuum gauge and see what vacuum you are pulling.
He didn't hook up a scanner to check to see that your o2's were oscillating to spec?
Plugs and wires swap can never hurt.
Clean your MAF.
Check your grounds on the coil.
Other than that, I don't know...fuses, swap PCM's maybe???

 

well i dunno he kinda said opposing statements that sorta made me think he tested the o2 sensors but then again he told me he couldnt get it to go into open loop or closed loop, whichever one it is that actually starts using the o2's.... but then he told me that the o2 sensors were like totally loaded up... like the lowest one of them would go was like 0.7xx and the other was like 0.9xx and those were about the lowest readings he could get... so i dunno

another question... does it matter where the grounds on the coil go? like i think all mine are on the same ground area and i didnt think they were before... and i cant find a diagram of where they go...

and also my fuel pressure tested out fine... so scratch that from the list too...

 

Unplug your o2's and see how it drives.
Grounds don't mater, as long as it grounds.

 

whats your iat reading, what thermostat are you running, what do your fans cut on at... sounds more to me like the car is loading up due to reading cold. is it the factory harness? reason i ask we swapped an ls1 into an extreme a few months back and the harness company had the o2 wires marked wrong. left was on the right and vice versa... ecm kept reading one side was lean and one was rich and dumping gobs of fuel to the wrong side. other thing to see, how old are the o2 sensors? reason being if they go bad, they tend to go on the lean side... post back up with some answers and i will see if i can help

 

well first of all ill throw this out there cuz i thought it would be sorta logical to try lol... but i unplugged the MAF and started it to see if it would run normal... and i knew it would still run rich but i figured it would make it run somewhat differently, but it didn't.... so i really don't think its my MAF, and i cleaned it like 3 months ago or so

the o2 sensors i am kinda wondering if that is what it is now, but they still puzzle me.... i only replaced one when it was bad like a year ago instead of two, but i think the other sensor that wasn't replaced was fairly new also by the previous owner... but the reason im not thinking its o2 sensors is because doesnt the car run off of the pcm at cold startup basically instead of the o2s until they warm up enough to get the right readings? because it runs terrible on cold starts and runs bad once it warms up...
today i drove it home from the dealership and it is prob. a 2 mile trip and it def. got warmed up on the way home and it ran bad the whole time.... and when i got in the driveway i put it in park and it died on its own....

so tomorrow's plans are to go get a new battery because the one i have right now isn't holding charge, try starting it and running it with the o2s unplugged and see how that does, check vacuum pressure, check all fuses, and then coming back here for more ideas lol, unless i get some more posts before tomorrow that is

oh yeah sorry i forgot to put it, but yeah its the factory harness, not sure on the IAT reading but the guy said it checked out fine, i have a stock thermostat in it which is like 190 or so i think, and my fans are set to kick on a little earlier because of my tune but im not sure where exactly... i'd say first is around 160 or so and both at 200 or somethin like that...

 

ah hah... tune...
who tuned it and when did it start running bad? if you unplug your o2's, all it is going to do is stay in open loop. (someone correct me if i am wrong)

before it started running bad, did you change any parts or anything?? sorry, its hard to diag over the net

 

indirocz28 on here sent me the tunes... im pretty sure he knows what hes talkin about... but no its actually ran the longest amount of time without messing up since ive had it without having to put any parts on it lol.... this car is so unpredictable its crazy.... one day it will run like a total raped ape, the next day it will take forever to start and putt along at like 5 mph... not really, but thats how i feel about it sometimes (lol thats what i get for buying an lt1 i guess haha!)

but yeah i was hopin with the o2 sensors being unplugged that it would strictly run in open loop or closed whichever it is whenever its cold and not run off the 02s at all just so it would tell me if its the o2s that are causin the problem... but i dunno if that is gonna work or not

unfortunately my car isnt like ricky bobby and it doesn't **** excellence in the mornings.... it just chokes itself out now and tries to kill itself

 

another question... today when i started it up to take it to the shop it sounded almost like i had a rock rattling around in a metal tube when i would get on the gas a little bit... like not saying i have a rock in a metal pipe but that is almost what it sounds like... dunno if its just something in my exhaust or what but it was just strange.... still no codes or anything but hopefully tomorrow ill find out more about it.... i also have a belt squeaking sound but i think its actually my power steering pulley... are power steering pulleys hard to replace? i tried searching for it on here but sure enough the first thing that came up when i seached for power steering pulley was some electrical bullshit and nowhere close to what i wanted lol