ehall

Okay, she's all back together. Now, it idles at 3k, with or without the TPS plugged in. The idle screw is tightened to max. There is play in the throttle cable and the cruise cable is disengaged, though it was engaged with no difference. It has heated up enough to come off high idle. Still no change.
I replaced the head, HG, belts, rollers, F crank seal, WP and all hoses. I ran all the vac lines. Nothiong obvious.
Where should I start?
TIA

ehall

BaBump!

ramius665

Hmm... I'd double check the vacuum lines. I had an issue with high idle and my ICV was the culprit, maybe start there?

JohnKoaWood

Hmmm, or maybe try using the Phone a friend option...

Throttle body, TPS, ISV, could be any one of these...

Scott H

For an engine to idle that high wouldn't it need more air than a closed throttle plate would allow?

AScholtes

My vote... vacuum leak post throttle body... verify all hose clamps are tight on the ICV hoses?

ehall

Hmm...so it idles higher to gain more air?

It goes into overspeed when driving and changing gears. As soon as the clutch goes, the damned thing will go to 6k. That was NOT a fun experience. In gear, it will drive the RPm down to just above standard numbers. Out of gear or off load, it just wants to run away.

AScholtes

I had a problem like this on a mustang a while ago. I changed the TPS and checked voltages etc on the TPS circuit. Culprit ended up being a bad ECM...err DME in our speak..

Bri Bro

The amount of air going into the intake is regulated by the throttle body. Air is bypassed around the throttle body by the idle adjustment screw and the ISV to obtain a proper idle. If you have a vacuum leak that allows air into the intake, the idle will go up and the engine will run lean.

Did you plug in the iSV?

odb812

Yeah, try disabling the ISV electronically with the diagnostic port.

ehall

Yep. Tomorrow I'll block the ISV to intake pipe port and see what happens. After that I'm going to check the diagnostic port trick.
Is there a semi-permanent bypass for the ISV?

odb812

I just disabled it at the diagnostic port for a couple of years. Raised the idle with the adjustment screw on the TB in the winter in VA for cold starts and lowered it back down in the summer. Other than that I left the ISV itself and all hoses in place.

ehall

Where is the diagnostic port? I've seen volumes of pics, but haven't put my paws on it.

odb812

I don't have a good picture of it but the red arrow in the pic below is pointing to it. It's got a round cover that lifts up with the catch towards the front of the car and the hinge towards the firewall.


Clarks Garage describes how to disable the ISV in step 3 of this writeup:
http://www.clarks-garage.com/shop-manual/fuel-08.htm

Ski

when it comes to TPS and testing, always found this to be well worth it. good luck

http://www.arnnworx.com/tps-repair.htm