I've got a weird high pitch noise comming from the engine bay and a high idle (2.5k). The noise has the same pitch as a belt squeal and volume but its definitely air. It is louder than my 4" straight through exhaust.

It started after i put my UIM back on, but i have double check and rechecked all the connections that go to the UIM. Someone thought it may be the Idle speed control selenoid because the white clip that went to it was kind of fubarred but i hardwired it just to make sure it wasn't that.

I'm getting the correct TPS readings from the haltech, and everything seems to be running fine. The car isnt' sputtering or flucuating at all, very stready and strong.

Any Ideas?

 

big vaccum leak. spray some carb cleaner around listen for the bogg. also if the iac motor is stuck open it will idle very high.

 

You double-checked all the connections to the UIM, but did you double-check that you tightened all the bolts? This happened to me once and I had only finger tightened them.

 

Your description of the squeal sounds like a gap in a gasket, or like jayk said, a very loose attachment.

 

Wouldn't a big vaccum leak cause the idle to bounce around and be rough? I know the bolts are torqued down. I have taken the uim off and back on again several times to see if i can figure it out but, i can't find anything.

I will check the gaskets.

 

A car with a speed-density based EFI system (like the FD is stock and the Haltech is - uses a MAP sensor as a primary input) will typically have a high idle with a vacuum leak after the throttle body.

It can be tricky to find a vacuum leak, but it's doable. Just need some persistance.

Dale

 

This has to be one hell of a vaccum leak then, i can't tell where its comming from because its so loud near the engine bay that it hurts my ears.

 

get a can of carb cleaner put that red tube on the end of it and shoot it at the joints, block off plates , anywhere after the tb and listen for change in idle

 

You need a piece of vacuum line about 2-3 feet long. Stick an ear plug in one ear and one end of the vacuum line in the other. Now use the other end like a stethescope to find the source of the noise.

 

Thats an awesome idea. I'll let you know how it goes next week after it gets warmer.

 

you probably didnt get ALL the old gasket off, im assuming you put in a new gasket on. Take off the UIM again and make sure you get all the old gasket off, the gap is causing air to get in and act like a reed on a saxephone. Ive had the same problem

 

You were right, there was a tiny little indentation on the gasket between the UIM and LIM. Put a new one on and it sounds and idles like a champ.