I have a 1996 TDI 300 disco. It has a problem while driving. As it is driving along at low speed ( not under power ) the engine drops to idle, ( about 750rpm), and then the "check engine" light comes on. When I push the gas peddle it comes back to life.

It has been to a landrover specialist engineer who has had the diesel timing tuned, and then replaced the potentiometer as it come up as a fault on an system scan.
I picked it up a couple of days ago, and the problem still occurs.
The mechanic has said he can't think what else to try.

I had thought there may be a diesel pressure sensor problem????

Can anyone think of anything else.

Have a '95 2.5 tdi and it started doing exactly the same thing to me this morning: chugging at low revs the engine dips (but doesn't stall) and the 'Check Engine' light flickers on, rev up and she's fine.

Would love to hear people's thoughts on this problem.

Sounds like same problem with mine, see here:
http://www.landyzone.co.uk/lz/f8/check-engine-light-122025.html

Thought I'd fixed it by replacing injector nearest bulkhead (EDC so has sensor) but the light still comes on, always after the motor has been running for some time and is hot.

Please keep us posted if you find the cause..

I'd check the alternator voltages and bearings, and all earth wires, as a start.

Cheers Paul have fitted an additional earth from battery to fuel pump mount to sort starting issue, wouldn't know how to approach alternator but I have a multimeter - shall do some reading up..

Have just bought myself a Disco 1 , 300TDI, last modell. Dident manage to get it home , 500 km , couldent get more than 2000 -2500 rpm - it just died if i tryed, and than I got RPM fall, rapidly with following : check engine. The seller tok it back and replaced a sensor and kick down wire. Helped some, but now after long run the RPM stopped at 3000 RPM. So no a LR service will replace another sensor, dieselfilter house, an diesel dyse? , and a air leack into engine. Hope this will work. Have waited 2 months for my car now............