[jeepofun]

I have a question for you jeep gurus out there. I just replaced my exhaust manifold on my 99 tj and the installation went fine (slow but fine) I re-attached my intake manifold and when I went to start the jeep, the throttle seemed to be stuck wide open. It is not from the throttle cable though because I tried unclipping it and it still revved wide open. Anybody had this problem or have an idea on what might be causing this?

I appreciate any help

[fastalkintn]

look at all your vacum lines, one may not be connected.

[Jim Shanks]

I will almost guarantee you that the intake manifold is not sitting on the 2 alignment pins that stick out of the head. If it was a vacum leak it would be a higher idle more than likely. This totally sucks, but you will have to take your power steering pump back off along and all the bolts that hold your intake/exhaust assemblies inplace. Then make sure it is seated all the way up against the head. This has happened to several people on another board and a few on this one. And almost to myself when I installed my Banks header. I caught it in time though.

What is happening is ALOT of extra air is coming into your intake via the open crack and your pcm is compensating by shooting alot of fuel into the mix so it doesn't run too lean. Hense WOT.

Good Luck,
Jim

[wrangler2002]

Jim,

I don't think he is running WOT. I think the duration of the injector pulse is driven by the position of the throttle body (it should have a sensor). His throttle body is fully closed so he shouldn't be seeing WOT conditions just a VERY lean mixture... unless he is in closed loop mode and the oxygen sensor output is over riding the TB position sensor.

Maybe his TB positioning sensor is not connected...

[Jim Shanks]

All I'm going on is what I've read from others and almost seen myself. If it is sitting ontop of the pins there is about a 3/16-1/4" gap on the whole underside of the intake assembly. Across 6 intake holes that would probably equal more than the throttle body being wide open. Hense WOT like idle.

If something like the TPS is unhooked, wouldn't it default to full off position? Maybe it is just a vaccuum line or something. Just trying to help him out like you.

Either way, just double and triple check your connections/lines, etc... to check what I am referring to, you should be able to see it from underneath with a bright light. Make sure the gasket is smashed between the intake and head.

Jim

[jeepofun]

Hey Jim,

What you said makes a lot of sense, mine is a banks header also. I will check that out. I was having trouble aligning the intake on those pins, so maybe I didn't quite get it on flush.

[wrangler2002]

maybe a feeler gauge can help

[Jim Shanks]

It does suck that you gotta take most of it back apart if that is the prob. But it sure does sound like a HUGE air leak somewhere.

A feeler gauge is a good idea. The smallest one ya got shouldn't fit in there if it's seated properly.

Good luck and keep us posted.

Jim

[SteveBad]

I don't know what it might be, but OOOOOOhhhhh I HATE when that happens!

[jeepofun]

Jim,

You were exactly right. I loosened all of the bolts off and gave it a wiggle and the intake manifold dropped down almost a quarter of an inch at the rearmost part. Tightened evertything up again and it works like a charm.

Thank you very much for your insight.

Don

[Jim Shanks]

Awesome, glad I could help.

Jim