TJ turns over but does not start

S

Sandberg

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Hi. I am new to this forum. I have a 2000 Wrangler TJ 4.0L in the UK. Engine turns over but does not start. Fuel rail is full and shows pressure when release valve is pressed.
I suspected problem was with ECU so had the unit reprogrammed in the States with the SKIM deleted in case it was an immobiliser issue (neither key would work). I disconnected the key surround unit. Reprogramming did not make any difference.

I think there is no spark. Any ideas, and how do I test if it is ECU or perhaps crank shaft sensor?

Also does any know of any Wrangler specialists in UK.

Thanks
 
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If you hook up an OBD-2 scanner to the port, does it give codes? Can it find the ECU? This was a big tell for me ultimately that pointed to my computer being bad, not operating properly. If you can, are there any codes?
 
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Thanks - never used an OBD-2 scanner. Any particular brand of scanner for the TJ? Does OBD-2 mean it will fit the TJ port?
 
When you first installed the ecm did the jeep crank for a couple of seconds and then die twice? Did you remove the immobilizer prior to installation of the ecm?
 
Yes it did start for two seconds. For those two seconds I thought it was fixed! It has been Skim deleted again but this time did not do the two second trick.



I had disconnected the key surround bit (by pulling out the connector) if that is what you mean by the immobiliser.



I appreciate your help on this.
 
Sandberg said:
No
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Then that's either the crank position sensor or the wiring leading to the sensor. Look up your wiring diagram and verify you have 5v at the sensor...and/or replace it... Mopar if you can find it...lot of folks have had good luck with Standard Motor Products and Napa Echlin.

-Mac
 
Sandberg said:
I thought that too so have changed the crank position sensor twice. If the ECU is faulty will the revs still register?
Click to expand...

I've never seen the revs register, fwiw. This forum is way over indexed on ECU problems, but it very well could be that. But first I would verify you have 5V & ground at your cam & crank sensors (at a minimum) with the key on, and that the wiring around those connectors looks good.
 
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hear said:
I've never seen the revs register, fwiw. This forum is way over indexed on ECU problems, but it very well could be that. But first I would verify you have 5V & ground at your cam & crank sensors (at a minimum) with the key on, and that the wiring around those connectors looks good.
Click to expand...

Have checked for 5V at crank and cam sensors and both are good. Red immobiliser light remains on which makes me think that there is still an ECU issue. Any ideas please, and suggestions on where to get the ECU reprogrammed. Thanks
 
Sandberg said:
Have checked for 5V at crank and cam sensors and both are good. Red immobiliser light remains on which makes me think that there is still an ECU issue. Any ideas please, and suggestions on where to get the ECU reprogrammed. Thanks
Click to expand...

You are in the UK. There was a thread about a month ago that some UK TJ's had a separate immobilizer in addition to SKIM, called a May and Schofield. Believe it was operated by a key fob. Possible you have this as well? SKIM keys here in North America are encased in gray plastic. Are yours? Also, the SKIM light in the North American cluster is yellow. You have a red immobilizer light on.

Edit. Tried but couldn't link the thread but you'll find the last reply to it on this forum dated Jan 2, 2004 entitled 97 TJ immobilizer.
 
Mac57 said:
You are in the UK. There was a thread about a month ago that some UK TJ's had a separate immobilizer in addition to SKIM, called a May and Schofield. Believe it was operated by a key fob. Possible you have this as well? SKIM keys here in North America are encased in gray plastic. Are yours? Also, the SKIM light in the North American cluster is yellow. You have a red immobilizer light on.
Click to expand...
 
Thanks. My key has grey plastic surround. I have had the skim delete done on the ECU and have disconnected the key shroud. The immobiliser light I am talking about is a red light fitted to the trim on a panel to the right of the steering wheel. I don’t have a key fob immobiliser. Do you know of any way to test if it is the ECU? Thanks
 
Sandberg said:
Thanks. My key has grey plastic surround. I have had the skim delete done on the ECU and have disconnected the key shroud. The immobiliser light I am talking about is a red light fitted to the trim on a panel to the right of the steering wheel. I don’t have a key fob immobiliser. Do you know of any way to test if it is the ECU? Thanks
Click to expand...

That red light you have is not something stock on our TJ's so not sure what that could be. Perhaps an aftermarket anti theft system? Suggest you trace it to whatever it leads to and find out. As for testing the ECU the guru on here is Mark at Wranglerfix, he replied to you earlier in this thread.
 
Wranglerfix said:
When you first installed the ecm did the jeep crank for a couple of seconds and then die twice? Did you remove the immobilizer prior to installation of the ecm?
Click to expand...

Mark
Having walked away from this in frustration, I am back to have another go. At the end of the thread someone mentioned that the red light I referred to might be an aftermarket fitting for an immobilser. I am sure it is related to the problem. However it does seem to join the main wiring loom which makes me think it is original, perhaps for UK only. Have you come across this before, and any ideas please would be much appreciated.

immobiliser light.jpg
 
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