Jeep Lost it's power
#1
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here is the deal. I got too used to my 4 cyl comanche. Now that i threw 33's on my stock geared 4.0 auto 99, it has WAY more power than my 5.38 geared 96 on 35's
something is not right here.
its a 96 4.0 aw4
the power only kicks in around 4250 rpms and even then it isn't too impressive. other than that it just kinda lugs along. I can still get it up to highway speeds no problem and cruise along just fine.
new parts:
plugs
wires
cap
rotor
cps
o2
air filter
fuel filter
alternator
battree
tps,iac,map are all good
cat is fairly new (could see through it when i put it in a month ago)
Hooked it up to the scanner and everything looks fine, no codes.
Not sure where to go from here.
any ideas?
something is not right here.
its a 96 4.0 aw4
the power only kicks in around 4250 rpms and even then it isn't too impressive. other than that it just kinda lugs along. I can still get it up to highway speeds no problem and cruise along just fine.
new parts:
plugs
wires
cap
rotor
cps
o2
air filter
fuel filter
alternator
battree
tps,iac,map are all good
cat is fairly new (could see through it when i put it in a month ago)
Hooked it up to the scanner and everything looks fine, no codes.
Not sure where to go from here.
any ideas?
Last edited by ktmracer419; 10-02-2009 at 05:39 PM.
#3
#4
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Year: 91 with lots of 01' parts
Model: Cherokee
Engine: 01' 4.0L
#5
#6
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I would check fuel pressure like what was mentioned on Naxja. I'm sure its fine but when is the last time you checked the compression and leak down?
What brand of plugs? I have heard non champions can cause problems.
What brand of plugs? I have heard non champions can cause problems.
#7
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never but if i cant figure anything out by this weekend im gonna go that route on monday
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#8
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Year: 1990
Model: Comanche
Engine: 4.0 I6
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pull the rail with the injectors on... cut the key on... see if you got a bad injector... takes 10min and dont cost nothin... not sure if it would be the cause but worth tryin anyway... like a lawn mower... 2 much fuel bogs it down...
#10
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did the actuation test with the scan tool, each checked out fine.
#14
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Year: 1993
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Engine: 4.0 H/O I6
#15
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Year: 1994
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Engine: 2.5L
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try running it with out a cat and muffler for a day just to see if it does any better and if it does then get new cats and mufflers if it dosnt slap the old ones back on.