this car has always idled around this speed. i was hoping it was just my bad opti causing it, but its not. when i try to command the idle speed to say 800 using efi live it jumps to 1100.
if been trying to figure this out for a while.i should mention i have a exhaust leak at the passenger side manifold. due the the difficulty of getting to is i haven't messed with it because im not going to do it twice when i get long tubes.so the exhaust leak shouldn't make it idle low.
so far i have done the following
new opti
new wires
ngk tr55 plugs
fuel filter
coolant temp sensor (for pcm)
different a4 trans same year though
tried differant iac and map sensors, same differance
tried setting iac
clean maf and tb, checked for vac leaks
tried different iat sensors

there are no dtcs
but if anyone knows how to read data from tts datamaster i have freeze frame and data log info and im not sure what most of it should be.from what i can geuss the fuel trims are wrong. heres a snapshot from data master the dtc err showing is from when my opti failed and i hadnt cleared the code 16 yet. so ignore that

 

have you checked the trottle position sensor it can do wierd things my tps was out of adjustment and my tranny was slamming into gears

 

does it come out of closed loop? knock count is high, could be sensing the exhaust leak and yes it could be caused by the exhaust leak.

 

i think i replaced it, before my first tranny whent out.ill have to look into that. it says .67v on there with it closed .

 

craby its the other way. the car starts in open loop then goes into closed loop. maybe the knock sensor? im pretty sure the fuel trims are wrong too. i think someone might have flashed the pcm

 

dang lol, i keep getting the two mixed up. i would tackle the exhaust leak before going to much farther. 02 sensors are effected by a exhaust leak so that would mess with your fuel. does not take much of a leak. 4 of my header bolts were lose, just enough to hear it tick and my mpg dropped bad and the idle was lower. tightened them up and it seems to have gone back to normal. has your leak gotten worse lately?

 

no, and it usually gets quieter when it warms up. i think theres multiple issues with this car. i finally got it to throw a code. i got on it on a straight strech in drive not od and it wrapped up to 6k before it shifted and i got a fuel mixture lean code, cel came on for a second and whent away so i ran the laptop.
so how the hell do i get to the
passenger rear exhaust bolt? ive never been able to get to it with a socket any suggestions? maybe its loose but i think its a bad gasket. i plan on drag racing the car this summer but i would like to solve this issue befor then and i have a spare mani if its cracked and a new gasket.i cant order my longtubes till the 5th at the soonest and i still havent decided on which ebay ones to get

 

so no one knows if the info of the datamaster screen points to something funny???

 

you wont be able to tune it properly [or should i say] "it wont run right till you fix exhaust leak" exhaust leaks also suck in air causing oxogen sensor to read a lean condition at higher revs.

 

550 is low?? mine usually idles about 600..