Thread: A D2 TD5 running problem that I now need to fix...

That fault seems very like throttle position sensor or it's circuit.... which 70A relays you mean?

Thanks for the prompt reply, SF. The relays are in the main fuse box. R3? and R6? Anyway, front 70A relay and 4th 70 A relay. I'll check the pedal cabling and pots tomorrow morning.

Cheers
Pete

A bit more investigation.... R6 glowplugs (may be 100A), R9 main relay (chattering intermittently).

Pete

I'm guessing loose connection in/to fuse box, so fuel pump relay is also cutting in and out resulting in fuel starvation, might even be a loose battery terminal, mechanics often disconnect the battery when working on a car, although having said that the OP's "starts instantly" seems to rule that out.

Thanks to the responders. Every bit helps.

Turned out to be fuel pump associated. The chattering main relay was being caused by feedback from an intermittent arcing in the pump itself. When I pulled the pump, I found that was the original at 398,000 km! Got to be some sort of record. And even though it was immersed in diesel, there was evidence that the electric motor was on the verge of failing completely - end bearings had failed and there were a couple of scorch marks where the rotor had been bouncing around. Alternator suffered the same fate with the brush box nearly disappeared. Fixed that with replacement brush box. Remarkably, the commutator was intact with hardly any wear.

So repaired and replaced, checked the timing for the umpteenth time. Fired up after a purge and checked for throttle response.

All good. Got rid of any lingering faults.... 2000 car with two track throttle was set up by whoever as three track. Not sure that would have made any difference to performance, but there you go.

But it's been a slog. Too old for this stuff.

Cheers, all.

Pete