hi guys ive got aproblem with my classic facelift the car drives ok but when you come to a set of lights the revs drop so far it nearly stall then the revs go up and like a yoyo checked allsorts of things to see what the problem is but still no luck please has anyone got any ideas its driving me crazy heeeeeeeeeeeelp

 

Symptoms sound like it could be the coolant temp sensoe has failed.

 

dump valve opening on idle or if a 99/00 car than maf sensor failed..

drive it gentle until resolved as if it is maf sensor you will kill the engine if you drive it hard in current state.

Simon

 

i wonder if its those spark plugs again?,if not could be vacuum leak,or maf?

 

i have tried the maf test car stalls when i unplugged it so that seems fine got to check dumpvalve mine is standard would it cause the same probs as aftermarket one also checked plugs yes mine is a my00 facelift

 

never 100% full proof that test.. owning a 99/00 car it is a good idea to have a spare maf anyway tbh.. so if the 90odd pound they cost doesn't break the bank then get one and swap it to check.

yes stsandard dumpvalve could cause issue still if spring has become too weak.

or vacuum leak as also suggested above

Simon

 

It was suggested that I clean my dump valve with some wd40, the car has cut out once since instead of all the time but still has the same problem with revs dropping right down and almost stalling.
It might be worth trying yourself?