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Hi, I'm still looking to buy a p38 thor.

Viewed one today, owned by a very friendly/helpful guy in Wales.

Two problems that are new to me.

Problem 1.
Car is not obviously overheating and temp gauge looks normal. Diagnostics shows silly high temperatures (150 cel?). Has new temperature sensor, same 'error' as old sensor.

I'm worried this could be rot in a ecu connector or loom.

The car has a problematic crank sensor. Runs for a few minutes, then obd shows dead crank sensor.
This is being replaced.

Problem 2.
Dash displayed "gearbox fault", vehicle then feels sluggish (as if in too high a gear). Seller feels this is related to crank sensor - but engine was running well (maybe just a single misfire 10 seconds before the gearbox error).

Many years ago, I was developing OBD systems and I cant think of a link (other than rotten loom) between these errors (gearbox, cranksensor, temp sender).

The seller feels all three issues are linked and should resolve when the crank sensor is changed.

I don't share the sellers view.

Am I being overly sceptical?

I don't expect to find a p38 without faults, but I am looking at expensive ones - hoping for something that is running well at the point of purchase.

All info greatfuly received.

Keith

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Did Gearbox Fault appear immediately the car was started? Did the starter struggle to spin it over? If battery voltage drops below 10V at any time, especially during cranking, it will bring up the gearbox fault message and put the gearbox into limp mode. Limp mode will only use third gear if the fault is detected while stationary or only 4th if detected when moving. This is almost certainly connected with the misfire which is likely to be caused by the crack sensor. If it is to be replaced, ensure a genuine Bosch is fitted and not aftermarket.

Earlier GEMS used two separate temperature sensors, one to drive the dashboard gauge and another to report to the engine ECU. It is the latter one that OBD will show. The Thor uses a single sensor that is actually two in the one body to carry out the same functions as the two separate ones in a GEMS. For some odd reason a bad earth will cause a high reading and not low as you would expect.

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Hi Gilbertd. Many thanks for the explanation, sounds like temperature sensor should be an easy test/fix.

The gearbox fault showed after ~5 mins driving. The engine was running well - then missed one spark - then ran well again. Shortly after running well again, the gearbox fault message was displayed. (IMO) the single miss would not have slowed the engine enough to effect the alternator output.

Starter motor turns engine nice and fast.

When working, the gearbox felt good (but I'm no expert).

Sounds like this could be a viable car, needing some rotten cabling addressing.

Thanks again.

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Kbs wrote:

Many years ago, I was developing OBD systems and I cant think of a link (other than rotten loom) between these errors (gearbox, cranksensor, temp sender).

I'd be interested in a chat about the development of OBD systems but that can wait until another time after your questions on thread have been answered.

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When i had a duff crank sensor on my GEMS, i would get "Gearbox Fault" when it went started acting up.

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Many thanks Aragorn. I didn't buy that car in the end.
Came close, but couldn't quite justify the price (in my head). Made an offer but seller felt he was better off keeping the car and selling in a year or two.

Of course, the seller may be right and he may have genuinely been offering me "an absolute bargain"