Thread: no longer smoth acceleration

mine is like this under load when its cold

Is it the same on LPG and petrol Vaughn?

Sounds like your once new spark plugs are no longer coping. This is very common with standard plugs. Try Bosch spark plugs, part number WR7DC+, gap as delivered, 0.8mm. I have had great success with these plugs, they have been very reliable on gas. If your Disco had been fitted with a traditional gas mixer system it would probably have backfired! Also check the ignition timing, I set them to 10 deg BTDC without any problems to date, I am talking 30-40 V8 LR's on gas here.

if your on petrol ide say its the fuel pump.

cheers phil

My previous gas cars have always liked a strong spark.

So check out the condition of the electrics: strong battery, good leads, clean spark plugs etc.

If changing the plugs doesn't do it then I would try changing the ignition module by the coil, about 1 in 5 Disco ignitions go weak in output after running on gas.

When I started the disco there was black sooty smoke coming out of the exhaust, it looked like an 200TDI

while on idle the revs would surge between 400 - 1,100.

It did this on both gas and petrol, I switched between the 2 at a set of lights and there was no change to the surging.

after 15 min of this in city traffic I pull over for a coffee before giving up the planed trip and heading back home.

Start up the car to go home, not much smoke but you could still see soot coming out, no surge, no lag on acceleration, just smelled really rich.

I get the feeling something has changed and the ECU has now accommodated the change.

What changes the mixture and how do I change it back again?

after that reply ide say the airflow meter has left the building, closley followed by the IAC valve.

see if you can borrow (off a running v8) a AFM and IAC valve. the IAC valve can be cleaned with carby cleaner and should work alright for a while, but ide deffinatly look at the AFM first.

cheers phil