SLROC Forum

Any help appreciated. I have a 4.0L V8 Discovery. It starts and ticks over ok'ish but when you accelerate it has a massive flat spot from 2,200-3,500 rpm this happens on gas as well as petrol. Changed the plugs and leads which made no difference. Had an infrared temp gauge on the manifold and when ticking over all cylinders appear to be around the same temp. One of the cats has a bit of a rattle. I suspect either a sensor or some other electrical issue rather than mechanical. Any ideas? Anyone with experience of v8's or has diagnostic kit near the Penicuik area that would be willing to have a look for some beer tokens would be made most welcome.

  Bob.

if your in falkirk are i can plug in diagnostics  for you if its a d2 v8

pm sent

Had the same, mass airflow meter was faulty

Afm is a likely culprit as Andrew says, get a good plug in done ideally testbook to confirm. If it is the afm then only use dealer supplied replacement, the eBay Chinese ones are awful!

Afm is a likely culprit as Andrew says, get a good plug in done ideally testbook to confirm. If it is the afm then only use dealer supplied replacement, the eBay Chinese ones are awful!

its not ther maf its down on no 1 cylinder
has ongoing cat problem faults time after time

It might be the cam thats worn, the couple ive done were worn at the rear tho, quite easy to check.