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CHECK ENGINE LIGHT strange troubles

650 views 1 reply 1 participant last post by  euro_zj  
#1 ·
about :
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hi, iam siting in the middle of nowhere , deep in the ex-comunist block :)
http://www.lonelyplanet.com/destinations/europe/czech_republic
Jeep technology knowledge is poor here. Noone can help me... :( Maybe someone of you can... THANXalot martin


MY BABY
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ZJ, 93, 4.0engine, 4wdFull QuadraT, laredo
Some 111Kmiles - superb condition. 20Kmiles riding by my self, without any troubles.
http://www.xtr.cz/kyzj/myzj/



PROBLEM
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before every engine start, i have to wait for the "check engine light"(CEL) start to glow. Until CEL start to glow (on+off), is not possible to run the engine. But engine kranks as well.
BUT this is different. IF the engine is warmed up, the CEL glow as usualy - after turn the ignition key. Soemetimes, sometimes in a few seconds after.
IF the engine is cold, mostly i have to wait some 5+ minutes before CEL comes on. More cold weather results more time to wait...

The jeep dealer diagnostic instrument shows NOTHING. The public ZJtrouble shooting code shows actualy 22.
I put a brand new fuel pump inthere.

IF the engine is cold, everytime before CEL glows, there is a very noisy realy to hear in the PDC = Relay #4 on http://www.xtr.cz/kyzj/relay.gif. Actualy this realy is brand new too.
Sometimes is the same noise even if the engine is warmed up.

I dont have a factory alarm/immobiliser built in. Thic car is equiped with some aftermaket one.

My ignition key unit on steering is brand new.


SOLUTION
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any ideas?
 
#2 ·
SOLVED CHECK ENGINE LIGHT strange troubles ZJ 93

Firstime i was thinking it is the batery - like MOABSTER wrote on jeepforum.com. After I cleaned the cable contacts and put a brand new baterry in, it was still the same :/

After, my local dealer replaced the car_CPU* with another one and my problem is gone :) YEP!

Iam lucky, cause i have now enougt on own used parts here, to built second GC (-:

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car_CPU*
iam not exactly sure about the right part name. It was the computer unit behind the coolant reservoair. Mounted on body, right side under front window.

Thanx alot for help to all of you guys!