fivepint

Hi all, just wondering how people test their MAF sensor without going to the dealer... I check the ECU for codes on a regular basis, back connector trick but Im sure this wont show up a failing MAF only a bown one? how can a perform a simple check in laymans terms please oh just in case car is a MY00 turbo 2000

~Cheers

P20SPD

iTrader: (1)

Park your car up and let it idle. If it sounds smooth, then it should be ok.

Remove the plug for the maf sensor, whilst the car is idling, and if the idle drops and becomes erratic then that would suggest that your maf is ok.

However, if there appears to be no difference in the idle of the car between maf plugged in and unplugged then that would suggest there is a problem.

Alternatively, find someone who has Delta dash (assuming MY99 onwards), and get them to check it.

Steven

fivepint

thanks Steven

WREXY

There is one symptom of the MAF problems that can't be checked without special diagnostic tools. You need either Delta Dash, Secs, or a select monitor. It is the worst symptom and it's the one where the MAF sensor starts to under read slowly slowly, causing leaner running slowly slowly till it runs that lean that the engine dets and cries "enough".

You need to have one of the three diagnostic tools I mentioned, the car being driven at WOT above 4000rpm in third and observing the O2 sensor readings.

Really, this procedure should be carried out once, say every 3 months, to catch a bad situation. You never know when those little buggers start to foul up. It's such a small item yet can destroy an engine. Quite a few engines have blown up due to faulty MAFs without bad running or weird idling issues. Just lean running, which you can't pinpoint without diagnostic tools. The car will start to feel quicker, (due to leaaner running), but who would be suspicious that it's due to a MAF starting to foul up?

The purchasing of Delta Dash, or a Secs would be a good investment. Especially for observing and catching a situation before it turns very expensive.

Cheers,

Wrexy.

fivepint

thanks Wrexy, hmm have to blag someone with DD now!!!

jameswrx

iTrader: (4)

Steven

I tried this and the instant I unplugged the maf the idle dropped but it picked back up again and sat there idling normally unplugged.

When the maf is knackered does it do this?, or is there no drop of revs in any way when you unplug it?