it seems that when my car is warmed up and i know that it is a little low on oil, that when im driving and come to stop the rpm's will hold at 1000- 1300 rpms. But i can give it a little grace tap to about 2000 rpm and the idle will sometimes calm down to normal. Being when the car is cold, or not up to operating temp, there is no helping the idle prob. I have replaced the idle air control valve and the problem still persists. So what im asking is any relevance between the Oil level sensor in the side of the oil pan? im on my last leg with this motor. I currently have the timing cover and oil pan off of the car for new gaskets and seals. So im thinking to help with the idle im going to drill the 58mm throttle body for the idle air passage. i have seen it helps some modified LT1's on here. Or is there anybody with a scanner in the 29673 SC area that can help, besides Hawk's since im on a limited budget here?

 

is it just that no one knows what could help, or that no one cares? im just askin opinions here. seems like everytime i post on here i get no kind of love or help. So again, does anyone know anything about this?

 

Have you verified the TPS voltage on the TB? With most after market TB's you have mod the TPS sensor to get the voltage right. That affects the idle greatly. I will try to remember this off the top of my head but do a search to make sure I'm telling you the right numbers. You will need a multimeter or a simple DC voltage meter to test this. The middle wire(again can't remember for sure so double check this) on the plug of the TPS sensor needs to be tapped or probed with the Positive lead from the meter and the ground for the meter can go to the battery ground. When the throttle blades are closed, the voltage should read .63 volts (Again double check this). At wide open throttle it should read 4.5 to 5.0 volts (again double check this). These numbers vary a little but if the voltage is to high with the blades closed it can cause a high idle. The holes in the side of the TPS sensor need to modified so that they have adjustment to be able to rotate it front to back in what ever direction is needed to get the voltage right if it's needed at all. Search on how to modify them and you should find a write up with pictures on the net.
There are a bunch of other ways to get it right but this is a product of the after market TB. Search on the idle air circuit for after market TB's and you will find a bunch of threads on it. The TPS voltage can help alot but to fine tune them it takes more in modifying the idle air circuit.
Another problem is some of them don't have the throttle blades set to the right angle at idle and the pcm struggles to obtain the desired idle rpm. Doing anything like changing blade angle or changing the Idle air circuit is best done with a scanner or data stream software that can show IAC counts. Thats what determines how far the IAC valve opens to let air in for idle. Try testing the TPS first to see if it's just a bad sensor or if it may need to be adjusted.

 

vac leak maybe... hard to guess without a very good understanding of what is causing the issue... if you plan on keeping the car try and get a cable and use your laptop to see what the IAC counts are?


other than that check for small vac leaks and double check everything...


edit... what jay said...

 

By the way no the Oil level sensor just triggers a dumy light as far as I know.

 

check to see if the plunger where the IAC valve is full of crud. it caused erractic idle on my car, only takes 5 min to check, other than that said vacuum leak is prolly the culprit