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Unread 06-23-2011, 08:38 PM   #1
flaneryjunior99
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1999 XJ Cherokee 
 
Join Date: Jun 2011
Location: Elkhorn City, KY
Posts: 3
runs great cold but when warm it runs bad.

my jeep runs great when cold but when up to operating temp it runs like crap, i checked the fuel pressure its good, no vaccum leaks, i can hook it up on a OTC Genysis it will show a ingnition coil #1 and #2 but i cleared it didn't come back on . I can watch it with the genysis when idling or driving no misfires on any cylinders. Could it be the ingnition coil bar?

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Unread 06-23-2011, 09:08 PM   #2
xjfever
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1995 XJ Cherokee 
 
Join Date: Feb 2008
Location: north Ga.
Posts: 14,212
It could be that it is suffering from heat soak which is common for a failing electrical component. Once it gets to a certain temp it doesn't work correctly but functions fine when cool.
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Unread 06-24-2011, 01:21 AM   #3
ratmonkey
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1997 ZJ 
 
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Location: , Pennsylvania
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Also possible bad o2 sensor. Fuel trims running stupid rich or lean?
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'97 zj 5.2, some stuff, some other suff, and some things that even work sometimes.

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Unread 07-06-2011, 03:43 PM   #4
flaneryjunior99
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1999 XJ Cherokee 
 
Join Date: Jun 2011
Location: Elkhorn City, KY
Posts: 3
the 99 only has one oxygen sensor i cut the catalatic converter off no change. replaced the camshaft position sensor no change, I replaced the ingnition coil bar no change.
It is showing p0351 and p0352 ingnition coil A and B circuit malfunction.
I broke into the harness traced the wires to the pcm nothing broken.
Ive had ppl tell me it is the pcm.
What do u all think?
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Unread 07-09-2011, 05:29 PM   #5
flaneryjunior99
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1999 XJ Cherokee 
 
Join Date: Jun 2011
Location: Elkhorn City, KY
Posts: 3
i put a pcm in it no change..
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