engine revs on start up after changing head gasket HELP!!!!!!!
07-11-2011, 01:32 AM
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engine revs on start up after changing head gasket HELP!!!!!!!
changed my head gasket a couple days ago and after putting the engine back together, went to start it up and the engine revs to full throttle by itself. not sure why its doing it and ive triple checked everything i can think of and i cant find anything wrong or out of place. does anyone have some insight for me or some advice? anything will be helpful because im stuck.
thanks to all in advance,
brad
thanks to all in advance,
brad
07-11-2011, 11:48 AM
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Year: 1997
Model: Cherokee
Engine: 4.0 L
is the speeder cable correctly installed ? maybee its to tight and puls just a little on the throttle. it dont need much to rev high without load.
let us hear what you found
gohd luck
let us hear what you found
gohd luck
07-11-2011, 12:06 PM
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Year: 1994
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Engine: 4.0 L/242 CID I-6 High Output MFI
Let us know. Good luck. Good suggestion, denmark, that would easily be overlooked after doing a head gasket lol
07-11-2011, 05:11 PM
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Year: 2000
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I posted almost the same problem yesterday.Replaed the head, new gaskets, [runs fine] but revs high. I've gone through it, removed and reinstalled the manifolds(with new gasket), clamped off vac lines,retorque head bolts. I'm stumped. Could it be the IAC or TPS? Let us know if you figure it out.
07-12-2011, 07:04 PM
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wnet through the whole engine and there werent any vac lines out of place or missing, and i checked the throttle cable and its actually a little loose so that couldnt be it. and its not just revving high, itll go all the way to redline. my pops in insisting that its the timing, but could i have messed that up just by changing the head gasket? and if i hear of anything else that it coud be ill be sure to let u know south12. im about to just tow it to a shop because its my dd and i cant afford to not ahave a vehicle. already lost my job over it so thats a whole new world of troubles.
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07-12-2011, 07:38 PM
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Year: 2001
Model: Cherokee (XJ)
Engine: 4.0L I6 Power Tech
What was the original reason for changing the head gasket?
Did you have the head checked for cracks/warp?
A possibility:
http://www.naxja.org/forum/showpost....8&postcount=12
Did you have the head checked for cracks/warp?
A possibility:
When you put the manifolds on the head make sure you line up the 2 dowels on the intake to the head. If these don't line up the manifold is aluminum the dowel can wedge in the manifold creating a nasty vacuum leak which will cause the idle to be very high RPM (ask me how I know).
07-12-2011, 07:38 PM
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Year: 1989 xj sport 2dr
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Engine: 12 hole bosch Injectors
bad vacuum leak under neath manifold where it bolts to head or brake booster vacuum line not hooked
07-12-2011, 08:06 PM
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Year: 1989
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When you leave the IAC unplugged it will rev to 2000 at least, that's when I shut it off. Check the harness to the IAC and before it. Could be something simple.
07-13-2011, 07:59 PM
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all vaccuum lines are in place, the manifold is in place properly, and all plugs are plugged. im callin it quits and takin it to a shop here in town that has a nack for jeeps. ill make sure they let me know what the problem is and ill post it up on here for everyone to know. who knows, might help someone in the future.