I there any way i can manually check the air flow mass sensor on my vectra

Question

ok sorry its a petrol on a 2000 plate..whenever i declutch the revs drop as if its going to stall but doesn't instead it'll pick back up again then drop then pick up and so on..occansionally it will stall but will start again no problem..was told it's a common problem on vectras and it's almost certainly the air flow mass sensor

Answer 1

If its the air flow mass sensor a light will come on on the dashboard - the orange one with a gearbox symbol.

The problem is fuel starvation not the air sensor - beleive me, i know.

Answer 2

on consulting my haynes manual here are the suggestions

1.air filter clogged

2.vacuum leak at the throtle body  or inlet manifold or asscociated hoses

3.worn ,faulty or incorrectlty gapped spark plugs

4.uneven or low cylinder compressions

5.camshaft lobes worn

6.timing belt slipped or fitted incorrectly

7.faulty injector/system fault

no mention of air flow sensor as i thought the car will run even if its unplugged.

Answer 3

If you can borrow one of a good car, you can swap it for yours and see if the fault still exists...  I have an Alfa Romeo 75 which I bought lately, and it was running sick... about 50bhp, until I changed the AFM, which immediately gave me all the power it should have had!

Answer 4

more info please is it deisel? petrol? and why do you need to check it

Answer 5

Hi iwould check idle by pass valve,probable its gummed up crankcase fumes,located on inlet manifold.

Answer 6

First check the obvious, air filter,air hoses ,vacuum pipes, then substitute for a known good one from a mate if poss or at worst a friendly breakers yard