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View Full Version : Solved Cleaning Mass Air Flow (MAF) sensor sorted out hesitancy on acceleration



andy_conf
23-02-2016, 12:23 PM
Hi

Wife's 1999 A4B5 1.8 Petrol 113K mile car has been hesitant when accelerating hard through 2500-3500 rpm. Been chasing this problem a few weeks and tried all the usual checks including new plugs, hecked ignition leads, new air filter....etc.

Cleaned MAF sensor with Halfords contact cleaner (takes 5 mins to remove, 20 mins to dry off).....result: car back to being very smooth....

If you have the right tools you can take the sensor itself straight out or you have to remove the whole unit from the air filter box (not hard anyway)...

Will probably clean this not when changing air filter every 10,000-20,000 miles or so (it's very clean even after 10K).

These cars are great quality if you just service them and give tlc. It drives like a new car even now.

Since 2000 have fixed following only:

2009 Central locking air pump (£20 off ebay guy who reconditions them)

2013 New Cambelt, tensioners etc

2013 Heater/Air control unit (£40 second hand)

2012 CV Joint front wheel

Rest has been normal servicing and wear and tear (tyres, brake pads etc).

Although parts are a bit more expensive if you get a good one and use second hand spares for some bits it works out OK.

Going to run her till she drops! the car not the wife :)

Put this up to share MAF experience....worth a quick fix of your car is becoming less smooth or hesitant be for all the expensive work using codes etc..

Andrew

Eshrules
23-02-2016, 02:29 PM
The only issue with cleaning a MAF is that it's rarely a permanent fix - it's a useful process for helping to diagnose a faulty one sometimes but replacement is usually unavoidable.

andy_conf
23-02-2016, 02:48 PM
The only issue with cleaning a MAF is that it's rarely a permanent fix - it's a useful process for helping to diagnose a faulty one sometimes but replacement is usually unavoidable.

As this has never been cleaned at all, it's worth a try to see how it goes before changing out.

After this many miles its bound to get a bit dirty which as I understand it causes poor sensor performance or response.

Rgds

Andrew

Eshrules
23-02-2016, 03:18 PM
As this has never been cleaned at all, it's worth a try to see how it goes before changing out.

After this many miles its bound to get a bit dirty which as I understand it causes poor sensor performance or response.

Rgds

Andrew

It is, which is why I said what I said.

I was just mentioning it in case this thread gets read and people assume it's the best way to fix a failed MAF...

They're practically considered a serviceable part now and I'm sure the last time I had to buy one they weren't much more than £30