02 kj blown engine or ecm?

[simond]

Ok just put my hand on a 02 kj automatic with a 3.7.. The guy told me maybe the engine is blown .... Here the fact

Engine choked on hygway and never restarded
It crank but won start
No compression on 4 cylinder (?)

Any clue??? Engine blowned sudently on 4 cylinder....sound's weird...

I ve cheked the rocker and they are all in place

Other thing.. I ve heard that the 02 engine is difrrent and all 03-07 are non compatible.. Is that thrue ?

Thank's to light my french lantern!
S

 

[Billwill]

Ok just put my hand on a 02 kj automatic with a 3.7.. The guy told me maybe the engine is blown .... Here the fact

Engine choked on hygway and never restarded
It crank but won start
No compression on 4 cylinder (?)

Any clue??? Engine blowned sudently on 4 cylinder....sound's weird...

I ve cheked the rocker and they are all in place

Other thing.. I ve heard that the 02 engine is difrrent and all 03-07 are non compatible.. Is that thrue ?

Thank's to light my french lantern!
S

You need to take the head off that bank and have a look if that piston and valves are damaged.

You can fit newer 3.7 engines to your 2002...there is a different reluctor ring on the end of the crankshaft that you have to change as well as on the camshaft sprocket I believe...if you search here and on the other Jeep forums you should find this information.


Here is one good link from the How To section:http://www.jeepkj.com/forum/f202/engine-swap-overview-53270/

 

[simond]

Realy usefull thank s budy!!
There s no way that might be the ecm?

 

[Billwill]

Realy usefull thank s budy!!
There s no way that might be the ecm?

How do you know that there is no compression on cylinder #4?

You need to first check for physical damage before replacing the PCM (CRD has ECM!). These PCMs are pretty robust.

If you do not have the Service Manual for your Jeep you can download the 2002 KJ Service Manual here...about 140 Mb...includes circuit diagrams:

Index of /manuals/Jeep/KJ

 

[simond]

Its not in cylinder# 4 but on 4 different cilynder

Not the firy time a i ve got pcm problem... Got to change it on my 06 kj to... That s why i ask

 

[JeepCoMJ]

The PCM in no way, shape, or form can cause a change in compression on this motor. These motors use mechanical timing and as such only a mechanical failure can cause this issue.


You will need to remove both heads. You may be able to rebuild the motor, if it's just failed valves, and if they didn't contact with the pistons.

Your PCM could have failed, but cannot cause zero compression