Ok. I have this problem with my idle creeping up above 1000 rpms while sitting there. It also has an issue with coming back down to smack dab 800 when I am driving it and come to a stop. it idles high and it takes a quick tap of the foot to bring it down and then it kind of creeps back up slightly very slowly..


The 02 sensors still throw a lean condition on left and right bank consistantly when the fans turn on and the car stumbles then idles slightly higher...



I have double checked and sealed all possible vacuume leaks. I have a brand new opti, fluidampr, plugs, wires, true dual roller timing set, electric water pump, coil, icm, 02 sensors, egr!, AIR!, everything is very nice in my car. This makes me think it is my computer tune that I got from pcmforless. I dont know anyone that can hook my car up just to double check the tune and see what is actually going on in the engine.

These few issues are the little gremlins that I want to work out so my car feels like a new car and not some finnicky old heap. I am startign to think they are the tune and it needs to be changed up a bit... Not sure but these little annoyances suck and I want them gone asap!

 

Why do you have a different tune but you list no engine mods?

You mentioned checking for vacuum leaks but what about exhaust leaks before the O2s?

Did you check the wires to the O2s for burned spots (even where they are over wrapped with foil)?

Replaced the fuel filter and cut the old one apart to see if it had water in it?

Have you checked the fuel pressure?

Have you checked the fuel injectors for proper spray pattern? For that matter, how old are the injectors? Have they ever been cleaned the proper way (not just a can of junk in the tank occassionally)?

You need a scanner to look at the signal from the O2. If the code you are getting is a 44 for lean exhaust, that means the PCM is seeing a signal staying below 200mV for 50 seconds rather than switching between about 900 to as low as 100. If you then disconnect the O2 you should see the voltage go to about 450mV. If it stays low, you know the wires (particularly the tan/white wire) is grounded.

You could disconnect the O2 and unplug the white PCM connector and measure the continuity of the tan/white wire to ground. However you really need to scan it to see what is going on.

 

mods are in my sig. I have CAI. Full shorty headers back. one high flow cat. magnaflow exhaust, electric waterpump, 58mm throttle body, no emissions, switched to standard t-56 and had the tune done for it at that time. creeping idle did not happen until I swapped transmissions and got the tune. 02 sensors are working fine and wires are mint. there are no electrical problems anywhere in my car. I have a scanmaster that shows me everything that is going on and things look ok. the fuel injectors are stock and have never been taken apart... the fuel filter was just replaced and my fuel pressure is dead on with my afpr. Only things that have not been replaced are the fuel pump and injectors. Now that you mention it I could double check the tightness of my header bolts but they seem to be ok.

How could the injectors throw such a consistant condition in the computer especially after this only started when I swapped transmissions and got a tune, not before.

One other question. if my tune was made for 1.6 rr's and I dont have them in yet would that cause this kind of problem.????

 

this thing sucks. I need to get under the car to check for the exhaust leak but I dont think I have much of a leak at all... my cutout actually stopped rattling somehow. Would a crumby MAF cause creepy idling problems and stumbling while taking off?? I had my computer tuned for a ported MAF. I have heard porting the stock MAF makes them unreliable and I am starting to think about getting a 1LE elbow and new MAF. It has become so consistant that even if I warm up my car... After a few minutes idling my 02 sensors throw a lean fuel condition on left and right bank injectors. My car feels like it spits power a little bit. the fuel filter is new. Stock injectors have never been removed... fuel pump seems fine. throws this code very consistantly then the light dissapears as soon as you drive the car.

 

just a thought what is the exact fuel pressure I need for my LT1 and to make sure I let the car run and take off the vacuume hose from the regulator then adjust correct? I set my fuel pressure before but I want to double cehck and set it again. I was also wondering what the procedure is for cleaning and servicing my injectors. What is used in doing the job etc. I think it might be a good idea to do this when I do the roller rockers. I NEED to find somone local who an hook my car up and doa datalog to see what is going on. This is driving my insane and I am sure somone could take a quick look and figure it right out in a day.