02 KJ CRD 2.5L running poorly and no acceleration or power.

[dhula]

IMO disregard the error codes for the time being, they are adding to the confusion ATM.

Check the mechanical side of things first, specially considering the previous history and the way it's running right now.

Doing a compression test as your first step will get you some way, at the very least it will tell you if there is a big job coming up or a somewhat bigger job because it's worse than you first thought.

Checking the timing is a good next step but also consider checking to see if any Vv's are burnt, bent, broken, stuck, etc. I have no personal experience pulling this engine down this far so can't comment but from all my readings it seams the Vv's should be OK when a Tbelt snaps as the rockers take the brunt of the punishment, it's not to say that they WILL be though.

Next you should check crank/cam posn sensors to make sure they are fitted correctly and sending the right message to the ECU.

After all that the engine should start and run somewhat OK (maybe even spot on, who knows) and you can work on sorting out any left over errors/fault codes.

Good luck with it all

[Rob.fer07]

Good advice. It does feel confusing when there's so much that could be the problem. I have read the same that the Vvs would be okay when the timing belt snaps and I was told that all the rockers were replaced. I haven't got a crank position sensor error code listed but I guess it'll be worth checking..

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[dhula]

Suggested checking Crank/Cam posn sensors as these two are important to triggering the big bang that goes on inside the engine at the right time. Not having an error code means the ECU is quite likely receiving a signal from these sensors as it expects to but you want to be sure the signal is at the right time, hence checking to be sure.

After checking Vv's and timing, getting these two sensors right is the next most important IMO as the ECU usually can't use a default for them - the ECU can usually insert a default/base when other sensors fail or don't give results within expected parameters
Think of the crank/cam sensors as you would a distributor/points in a petrol engine (for those that remember distributors and points ), they signal the correct posn of the crank/cam and tell the injectors to squirt.

[Billwill]

I agree that the cam/crank sensors are a good thing to replace.

The injector codes for cylinders 1 and 4 are a cause of concern while the MAP sensor codes were caused by the OP running the engine with the MAP disconnected.
Would be nice to get the codes cleared but these early KJs with their PCI bus are difficult to find code readers that work!

I have the identical 2002 Export CRD 2.5 L and at the time of the release of the new 2.8 L motor the press release stated that the new engine would have the rockers snap off if the valves hit the pistons!
So maybe our old 2.5 L engines will not be so lucky if this happens to them!

[jaffazoom]

I know with my 2005 KJ crd
It keeps the codes till I reset them via the obd2 port.
If you are reading the codes from the dash display I'm assuming you might not have an obd2 adapter. If this is the case you might want to clear the codes and see what is actually there.

[Rob.fer07]

Can anyone recommend an OBD2 adaptor that works with these KJs? I have two different adaptors and they both fail to give me any reliable info or clear codes. However they both work with my other two cars, Nissan and Holden.

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[Rob.fer07]

I had a mobile mechanic come out and give me a diagnostic scan and opinion. He cleared all the codes then ran the engine. He noted that the RPMS could not reach higher than 150, apart than that he said there was obvious error from the engine running the way it is. He's opinion is that the head timing (valve timing)wasn't done correctly. I was quoted $1000.

The mechanic reckoned these Jeeps have hemi engines which are chain not belt driven which I'm pretty sure i's wrong. So paying $1000 for a possible solution?


There is no codes showing or cels after they were cleared.


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