Tacho on the blink

wander · 31st May 2008, 09:24 AM

My tacho on 97 300tdi disco has started jumping all over the place. At idle sits fine but soon as i take off tacho goes between 2000rpm and o.At 100 k's it moves between a 1000rpm and 2000 rpm all the time .Any ideas would be appreciated.

**awabbit6** · 31st May 2008, 09:33 AM

Have you touched anything on or near the back of the alternator recently? Mine is now doinig this too (again). I managed to fix it for a while by replacing the terminal on the end of the tacho wire on the alternator. The wire itself is very hard and feels brittle - possibly due to the heat fromt he exhaust. I'm going to replace as much of the wire as I can (without going too far into the harness) and see how that goes.

Paul

**loanrangie** · 31st May 2008, 09:54 AM

Mine was doing the same up untill 2 weeks ago, i pulled the connector off and just nipped the spade connector closed a bit so that i had to force it back on, removed/ replaced a few times to clean the contacts and now good as new.

**Disco95** · 31st May 2008, 07:12 PM

All good suggestions, if symptoms persist, get you alternator checked.

wander · 2nd June 2008, 05:38 AM

Thanks for the suggestions will try tonite have been away .

**chev28** · 3rd June 2008, 05:27 AM

This happens to me every month or so and I remove and replace the spade connector on the alternator a few times to clean it up and it works fine again. One day soon I am going to replace as much of the wire as I can get to.

wander · 3rd June 2008, 06:08 AM

Thanks for the help,cleaned spade connector and refitted all is working well again.This seems to be a common problem as our trucks get older.

Thread: Tacho on the blink

Thread Tools