studdering/ideling problem

[white5o]

i have an 88 5 liter everytime i start my car it idles low and bounces for about 30 seconds and sometime when driving it hold idle high like 2000 rpm turn off the car and start it again like nothing happened its back to normal for a bit

[crimsonblack]

You might want to check the Idle Air Control Motor that mounts on the Throttlebody. It controls changes in the idle caused by loads on the engine. A faulty unit causes surges and poor idle quality. Check the link for price and photo from Late Model Restoration.

http://www.latemodelrestoration.com/search.aspx?searchKey=LRS-9715A

Their site shows the part at $89.95, but their catalog shows the 5.0 unit at $72.95.

[white5o]

thanks in gonna check that out

[Nicoleb3x3]

I replaced mine...it can cause those issues
consider autozone: http://www.autozone.com/servlet/UiBroker?UseCase=C001&UserAction=performSearch&Parameters=Auto+Store%7C%7EREGULAR+PARTS+LOOK+UP%7 C%7EIdle+Air+Control+Valve

let us know if that's not it...because there's a long list of things to check; but the IAC is at the top of that list

[crimsonblack]

Not bad $60 from AutoZone in my area. I think I need one too... got some idle issues and a surge when stopped at the light when it gear sometimes. But... it will wait until the other stuff is done.

Hope if fixes you problem.

[Nicoleb3x3]

an egr valve not seating correctly can cause surging at idle and low rpms under 1500
this is because of buid up which can sometimes be cleaned out with carb cleaner
you can test an egr at autozone using the vacume tester

I found my surge was because of my egr, but not because the egr was having the issue i just mentioned; but because I had the wrong vacume line hooked up to it and it constantly had vacume and it never seated/sealed at idle!

it's because of tracing that problem, I learned about all the causes for this stuff
I bought an IAC before I found the problem, I actually have two of them if someone wants one; I know one of them is good since it was never broken it was my egr vacume line. I kept the new IAC just because it was new and shiny aluminum that helped under the hood appearance a bit more.

[crimsonblack]

My turn to be stupid. I know what the EGR Valve looks like, but where is it on the engine?

[Nicoleb3x3]

attached to the throttle body, in the back (it's kinda roundish in shape)
the opposite side of the throttle body (front) where you find the IAC (long and skinny)