Engine redlines after start
#1
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Year: 91
Model: Cherokee
Engine: 4.0
Engine redlines after start
Just replaced my stock header with a Gibson GP400 and it fits perfectly but now when I start it it redlines and I've checked every possible issue it could be and I'm well and truly stumped. All the vacuum lines are good, the bolts are torqued in place and everything is flush with the gasket. I have no idea whats going on
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Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
X2.....Are you positive it's seating right? if the new header flange were thicker than the intake you might have a mongo vacuum leak. (since the washers on the bolts won't pull the intake manifold in) The washers should be flat on there. You are sure the throttle is coming all the way home, and...no major lines off, like the power brake booster?
I don't think it can rev like that if it's not getting air.
I don't think it can rev like that if it's not getting air.
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#8
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Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
If the new flange is thicker I don't think the bolts are snugging in the intake manifold. For some reason I had my engine wet last week and I noticed it held a little water in that little space between the gasket and the head. (just a narrow 1/8" space). I went ahead and started it, curious if it would get sucked in by an intake leak. It didn't! (yours might?)
#12
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Year: 90,84
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Engine: 4.0,2.5
What I meant was you could put some water there and see if it gets sucked in. Since you don't want to red-line it like that again, have someone else crank and fire it for just a second. Then again, if the exhaust flange is thicker you already know the bolts are not holding the intake firm.
#14
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
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