'99 to '96 Engine Swap? HELP!!!!
#1
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Year: 1999
Model: Cherokee
Engine: 4.0L
'99 to '96 Engine Swap? HELP!!!!
I'm in serious need of help. I dont want to dump new parts into this thing trying to figure out why she's not starting only to have her still not start.
Long story short engine blew on '99 4.0L XJ and been replaced with '96 4.0L engine by old owner. It cranks but wont start.
What needs to be done??
Long story short engine blew on '99 4.0L XJ and been replaced with '96 4.0L engine by old owner. It cranks but wont start.
What needs to be done??
#2
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Year: 2001
Model: Cherokee
Engine: Inline 6
Start with checking your distributor cap, wires and spark plugs. Replace all if bad. Check fuel pressure. Clean up all your ground wires. New gas etc.
What does it do when you try and turn it over?
What does it do when you try and turn it over?
#3
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Year: 2001
Model: Cherokee
Engine: Inline 6
Also did it run before you got it from the previous owner?
Your 1999 computer might not be compatible with an older engine like a 1996 and earlier.
Your 1999 computer might not be compatible with an older engine like a 1996 and earlier.
#4
Crank position sensor check to see if you got spark if not I am very Cretan that's the problem. The old owner probably damaged it installing the new motor but check all your grounds first that could also be the problem other wise the motors from 96 and up too 99 are the 100% the same and 2000 - 2006 are the same just a different head then the 96-99 to make up for a coil on plug set up . so no matter what year if the wiring was set up right it will run
#5
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You need; Air, Fuel, Spark and Compression to fire an engine, your lacking one of those items!
Check to see if you have injector pulse. Use a noid light at one of the injector plugs while cranking to see if you are getting fire. If so then you have to move on to a spark issue and you have eliminated the CPS. It would have to be either no fuel pressure or the distributor is indexed improperly.
Was the distributor ever removed then installed incorrectly? If the distributor has been out you need to make sure it is indexed properly.
The rotor should point to or just past #1 plug wire terminal on the cap. To do this you MUST have #1 piston at Top Dead Center, compression stroke.
With #1 TDC compression stroke, pull the distributor out and drop it back in with the rotor pointed to the #1 plug wire terminal
I'll bet money its out 180 and set on the exhaust stroke.
Check to see if you have injector pulse. Use a noid light at one of the injector plugs while cranking to see if you are getting fire. If so then you have to move on to a spark issue and you have eliminated the CPS. It would have to be either no fuel pressure or the distributor is indexed improperly.
Was the distributor ever removed then installed incorrectly? If the distributor has been out you need to make sure it is indexed properly.
The rotor should point to or just past #1 plug wire terminal on the cap. To do this you MUST have #1 piston at Top Dead Center, compression stroke.
With #1 TDC compression stroke, pull the distributor out and drop it back in with the rotor pointed to the #1 plug wire terminal
I'll bet money its out 180 and set on the exhaust stroke.
Last edited by xjtrailrider; 12-13-2011 at 09:38 PM.
#6
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Year: 1999
Model: Cherokee
Engine: 4.0L
Crank position sensor check to see if you got spark if not I am very Cretan that's the problem. The old owner probably damaged it installing the new motor but check all your grounds first that could also be the problem other wise the motors from 96 and up too 99 are the 100% the same and 2000 - 2006 are the same just a different head then the 96-99 to make up for a coil on plug set up . so no matter what year if the wiring was set up right it will run
You need; Air, Fuel, Spark and Compression to fire an engine, your lacking one of those items!
Check to see if you have injector pulse. Use a noid light at one of the injector plugs while cranking to see if you are getting fire. If so then you have to move on to a spark issue and you have eliminated the CPS. It would have to be either no fuel pressure or the distributor is indexed improperly.
Was the distributor ever removed then installed incorrectly? If the distributor has been out you need to make sure it is indexed properly.
The rotor should point to or just past #1 plug wire terminal on the cap. To do this you MUST have #1 piston at Top Dead Center, compression stroke.
With #1 TDC compression stroke, pull the distributor out and drop it back in with the rotor pointed to the #1 plug wire terminal
I'll bet money its out 180 and set on the exhaust stroke.
Check to see if you have injector pulse. Use a noid light at one of the injector plugs while cranking to see if you are getting fire. If so then you have to move on to a spark issue and you have eliminated the CPS. It would have to be either no fuel pressure or the distributor is indexed improperly.
Was the distributor ever removed then installed incorrectly? If the distributor has been out you need to make sure it is indexed properly.
The rotor should point to or just past #1 plug wire terminal on the cap. To do this you MUST have #1 piston at Top Dead Center, compression stroke.
With #1 TDC compression stroke, pull the distributor out and drop it back in with the rotor pointed to the #1 plug wire terminal
I'll bet money its out 180 and set on the exhaust stroke.
#7
Have you checked your coil for some odd reason I have changer over 40 of them on jeeps and dodge at my shop this summer all of them had a weak orange spark and if you took the coil off and looked at it the case was split
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#8
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Year: 1999
Model: Cherokee
Engine: 4.0L
I know the CPS reads notches in the flex plate and we had to bolt that to the TC earlier. If the flexplates are different between the two years that would throw off timing and injector pulse. Right? But are the flexplates different? I wouldn't see why they would be. Or could we have put it in wrong? The older models could only be bolted on one way i know that, but I'm pretty sure the newer ones can be bolted straight on.
#9
So it starts sometimes and then it wont it's got to be the CPS and the the flex plates from 87 - 06 are the same on the 4 L try this next time it dose not start get someone to tap the CPS well u crank it if it starts that's her and the CPS is a magnet so it could still be damaged even if it dose not look like it
#10
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Year: 1999
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Sorry about the confusion. but no it hasn't started at all. I meant sometimes ill have spark and some times i wont. And are the flexplates the same for the 99 and 96? or different? I'll try that too though. thanks.
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Check the all grounds there is one for the coil that attaches to the coil mounting studs, that was the problem on a buddys jeep last month. Check CPS per manual, also wanna check the Cam Position Sensor (disc under Dist. Rotor w/ 2 wires).Make sure battery has a full charge the computer needs to see 300 RPM before it will trigger spark IIRC.
#14
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Year: 1999
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Check the all grounds there is one for the coil that attaches to the coil mounting studs, that was the problem on a buddys jeep last month. Check CPS per manual, also wanna check the Cam Position Sensor (disc under Dist. Rotor w/ 2 wires).Make sure battery has a full charge the computer needs to see 300 RPM before it will trigger spark IIRC.
#15
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Year: 1999
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Bump please!!
I hope my post is still alive cause ive still got the problem. Today i put in a 99 Camshaft Position Sensor(Stator). And same problem! Although it did fix the random spark. Now its firing like it should but it still has a weak orange spark. We cant even get a sputter or anything with a good dose of starting fluid. So please any one with an answer...? Im debating on putting in a 96 computer.
I hope my post is still alive cause ive still got the problem. Today i put in a 99 Camshaft Position Sensor(Stator). And same problem! Although it did fix the random spark. Now its firing like it should but it still has a weak orange spark. We cant even get a sputter or anything with a good dose of starting fluid. So please any one with an answer...? Im debating on putting in a 96 computer.