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jasontibbs 04-26-2013 09:53 PM

2.5 nightmare
ok so this is the long version.... a buddy had me bring his jeep over to do some repairs and holys$%t this thing is tore up. first a little history the motor has 12000 miles on a rebuild that was done at a rebuilder in chicago.then the motor sat for 8 months till it was installed.then the motor was installed and went through a proper break in period. at roughly 10000 miles it started blowing the dipstick out of the tube about 2 inches and would push a little oil out every now and it is in my garage (along with 2 more project builds).. it has also got another issue.when trying to start it there is no CEL but after trying to start it 12 to 15 times the CEL will come on and then it will start. now is where i am having a problem i have done a compression check
#1 has 150 psi
#2 has 145 psi
#3 has 143 psi
#4 has 150 psi
so i did a leak down test and the results are
#1 10%
#2 15%
#3 12%
#4 10%
all are within acceptable specs so now i checked the pcv valve and vaccum line and system all good with minimal oil in the pcv line and the scavange line that goes to the throttle body. so i cleaned them anyway so with these two issues let me add 1 more.
when you try to start it and the CEL come on so do the headlights but just dim not normal brightness for low beam almost like a dead flashlight.

so i hope someone can come up with some ideas cause i am lost at this point. i am thinking small crack missed during rebuild possibly. and during leak down test you cannot hear where the leak is i have tried smoke in all places watching for movement but get none
hopefully some has an idea.......:banghead::banghead::banghead::deadhors e::deadhorse::deadhorse:

thanks guys and gals

jasontibbs 04-27-2013 11:06 AM


C.L. 04-27-2013 11:15 AM

Sounds like the main harness is partially melted and some of the wire cores are touching. A buddy of mine with the 2.5 had similar issues (would sputter and die when wet, fuel pump would intermittently lose power, sometimes wouldn't start, etc) that were traced back to a connector that had sagged down enough to touch the exhaust. Once ONE positive wire melted to the exhaust it shorted and melted insulation off other wires further up the harness. They were randomly contacting/jumping and wreaking havoc with the electrical system, but never blew fuses for some reason...

jasontibbs 04-29-2013 10:56 PM


Garyk 04-30-2013 11:16 AM

Agree with C.L. on the wiring, something is shorted or connection is bad by the sounds of it. If the engine is blowing oil and blowing the dipstick out, there has to be excessive pressure in the crank case, Did you do the compression test and leak down when the engine was hot? There's only a few causes of blowby, cracked/holed piston, cracked ring, cracked block or blocked/faulty emissions

jasontibbs 04-30-2013 01:17 PM

But wouldn't either the leak down or compression test shown that

Garyk 04-30-2013 03:00 PM

Sometimes no, sometimes a crack will open up after the engine gets warm.....I saw once where the ring gaps were all lined up...not too common unless installed wrong.

What year is this engine?

jasontibbs 04-30-2013 04:26 PM

94 but the engine was rebuilt 12000 miles ago and developed this problem at 10000 miles

jasontibbs 05-07-2013 07:23 PM

Update ..... ECM fixed starting issue now on to the crankcase pressure issue

jokerchief462 05-07-2013 10:38 PM

Take the valve cover off clean the baffles at the PCV or CCV. Replace the hoses to the valve cover with new just to make sure they aren't collapsing when warmed up. Check oil level and ensure it is not over filled. The oil pump has a pressure relief at 75psi so it should be regulating the oil pressure for you. If not I would suspect the pump if nothing else is found. From your beginning numbers you have a lot of life left in the engine. See how all that works. I would hate to just jump on the pump first.

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