Rev counter flares up and down when engine cold

[beefbeefbeef Lurker Find all posts View Profile Close beefbeefbeef]

Fellas

When I start my 120 from cold, the revs flare up and down two or three times then settle on the normal idling level, runs sweetly thereafter. I'm sure it's getting worse i.e. it's going higher and lower to the point it almost cuts out.

Not a major problem at this stage but I'd like to know what's causing it.....

[mjrandom Out of control poster! Find all posts View Profile Close mjrandom]

I am guessing dirty maf sensor.

[beefbeefbeef Lurker Find all posts View Profile Close beefbeefbeef]

Will get some maf cleaner and give it a blast.

[beefbeefbeef Lurker Find all posts View Profile Close beefbeefbeef]

Will get some maf cleaner and give it a blast.

Just an update on the above. Bought some of the MAF cleaner, took out the sensor unit and I could see straight away that one side of the sensor was black with soot, the other half was silver. The cleaner didn't shift it straight away so I used a piece of kitchen roll and very gently rubbed it. When it was silver I let it dry and then put it back.

Results - brilliant. Revs have stopped flaring up and down. Throttle response is a little sharper. Will post again if fuel economy improves, too early to say.

Recommend it to anyone.

[VKPrado Avid PP Poster! Find all posts View Profile Close VKPrado]

Good to hear you had a positive result. Just be very careful rubbing the sensor and ensure you remove any residue from the kitchen roll.

[beefbeefbeef Lurker Find all posts View Profile Close beefbeefbeef]

Good to hear you had a positive result. Just be very careful rubbing the sensor and ensure you remove any residue from the kitchen roll.

I was very careful because i had read you are not supposed to touch the sensor - but that dirt was firmly stuck on!

Fuel economy has not improved as far as i can tell but, as said above, the car runs smoother so it was worth doing.