Thread: Caught by the old Shopping Centre Trick

Originally Posted by dirtdodger

I found that the engine would turn over on the starter quite fast..... I even went through the lock, unlock cycle.

Never experienced radio/electromagnetic interference myself but from what I understand if you can lock and unlock and the engine turns over then you do not have radio/electromagnetic between the key fob and the immobiliser.

I'd vote for the look else option.

From your description of the starter motor turing over fast and from my experience, it sounds as though it's a starter motor problem.

Starter motors will spin fast and make a "whining" noise if they aren't catching.

I'd be checking that out as a beginning.

Dirtdodger

Sully is closer to the solution I would think. Sounds like the starter is not engaging the flywheel as per normal and if you have pushed the car 100 metres or so this may have just placed the flywheel in a better position to engage. Check your starter is not lose. In any case more inclined to believe it's related to the starter.

Regards
Andrew

ring gear on a 2001 model would not have any dead spots on it already would it moveing it 100 yards in netural would not move the ring gear

Is it a petrol engined model? If so, this could be the first manifestation of a classic electronic ignition failure. The failure occurs and rights itself after a short period. The failures come at shortening intervals and with longer recovery periods until total failure occurs.

Originally Posted by Sully

From your description of the starter motor turing over fast and from my experience, it sounds as though it's a starter motor problem.

Starter motors will spin fast and make a "whining" noise if they aren't catching.

I'd be checking that out as a beginning.

Thanks for the responses people.
I probably did not explain myself correctly in describing the problem..

The starter was and is operating correctly........The engine was rotating. A little faster. It had time to wind up to speed without fuel or ignition.

Because the alarm light was extinguished ( which usually indicates a correct disengagement of locking/alarm/immobilizer) I discounted the supermarket interference.

However, electrickery can be devious stuff to diagnose at times.


That is why I wondered if anyone has had the same symptoms when caught outside a shop with a wireless barcode scanner operating.

I am suspicious of the fuel pump. But do not wish to go there unless I have to. No codes were thrown by the engine ECU.......which points to maybe an incomplete disengagement of the immobilizer.

And........so far.....I cannot reproduce the fault.
Trying to find a fault when it is not there can be somewhat difficult.

Go back to the shopping centre carpark, with a willing helper (to push!) and try to reproduce the problem. Same time of day if possible.

If you can reproduce the problem, it ain't your discos fault, it's interferance I reckon.

It failed again today.
But, nowhere near any electronic interference.

Started ok when cold, failed to start after a short trip.
Tow truck to get it home....and still failed.

I checked the codes and found nothing.

By this time it was time to stop and have a read of Rave on the peculiarities of the Bosch Motronics and engine sensors. (When everything else fails....it's time to read the instructions....and do some googleing)

I found that some P38 Rangies with Bosch Motronics can have a problem with their Crankshaft Position Sensors (CKP), and throw no codes.
Hmmmm....Rave mentions that a faulty CKP on a Disco can cause the engine to crank and not start, with no codes thrown.

Eventually the car started 3 hours later, and I noticed that there was no tacho indication for a few seconds after start. The engine gave a bit of a cough, and the tacho started to read.

The tacho is driven from the CKP via the engine ECU.

I removed the CKP (which is a real fun job) and found the probe completely covered in fine metal fuzz.( from the starter and ring gear apparently).
Rave mentions that a CKP probe contaminated with ferrous metal will cause a number of faults.
Including failure to start, and tacho failure.

Whether the fault is fixed, I will find out when it goes back together, and starts EVERY time.

Thanks for the input people.
If anyone has had similar problems with a D2 V8, please post.
It would be nice to know if I am on the right track.....or not.