Please help! My 94 has developed a surge at idle after warmup. the tach will jump iraticaly, and idle up for a second, then normal and back and forth like that. I replaced the iac but to no avail. I have a slight oil leak from the intake ( i think) but no vaccum leaks that i can find. any ideas?

 

I know you say you don't have any vacuum leaks but thats sure what it sounds like.

 

Check your fuel pressure.Could be a bad fuel pressure regulator or pump.Just a thought!

 

Injector orings leaking vacuum @ intake will cause that problem to. Try spraying carb spray arounf intake gaskets and injector orings where the injectors go into the intake. Other than that, would have to see scan tool data to properly diagnose your problem. Have you checked codes yet?

 

won't set a code. sprayed carb cleaner around injectors earlier- and intake- no effect at all. I also replaced ect (figured it couldn't hurt) It did this a couple of times a year ago and went away as fast as it showed up. now it's constant

 

How do you know it didn't have an effect?

Did you put a brick on the gas pedal? Block the throttle body arm?

What did you do, before you sprayed the carb cleaner, to increase the idle to a STEADY idle, WHICH YOU HAVE TO DO, so that you know when the carb cleaner has hit the leak that you have???

I suggest you do it again, and spray JUST A LITTLE AT A TIME, and wait for the spray to dissipate, before hitting another TINY spot. ...

 

Maybe you don't have correct fuel pressure?? Correct injector pulse?? I tell ya,sometimes when our cars have even a slight problem it seems it will either solve itself or a miraculous intervention may be in order,LOL!!! Good luck,and tell us what happens,ok???? Joe

 

will do!! i am going to look for a leak again, and test fuel pressure. i'll post the results as they happen