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Model specific boards => Golf mk3 => Topic started by: cedar on 08 November 2011, 16:44

Title: 1997 Mk3 MAF air sensor
Post by: cedar on 08 November 2011, 16:44

A friend has got a Mk3 GTI with running problems. On idle it is rich, hunts and chugs but doesn't cut out, it drives but feels lumpy, revs okay. The system shows a fault - Lambda sensor upper limit. We have fitted a new sensor as the car has done about 140K and cleaned out the throttle valve and the MAF, they both now look spotless. If with the engine running on idle we dis-connect the wiring to the MAF the the idle seems fine, when it's plugged in again the engine starts to hunt after a few seconds. The question is, does this definitely point to a faulty MAF? Would you risk buying a second hand one from ebay?

Title: Re: 1997 Mk3 MAF air sensor
Post by: tweed on 08 November 2011, 17:22

I would risk it mate.

Go to the classified and look for someone braking a mk3. will be cheaper than ebay  :wink:

Title: Re: 1997 Mk3 MAF air sensor
Post by: madmanmart on 08 November 2011, 18:05

Ive got a selection of good 8v MAFs - £10 each

Title: Re: 1997 Mk3 MAF air sensor
Post by: cedar on 08 November 2011, 20:15

Thanks for the replies. It's not my car and I won't see the owner until tomorrow but £10 seems fair to me madmanmart, how much would it cost to post to Cornwall.

Title: Re: 1997 Mk3 MAF air sensor
Post by: Wayne on 08 November 2011, 20:50

Makes more sense in the long run to get a service exchange unit from Bosch.

Title: Re: 1997 Mk3 MAF air sensor
Post by: cedar on 20 November 2011, 17:27

 Tried 3 MAFS now but still runs rich and hunting on idle,  if we disconnect the MAF it idles OK . If we reconnect, after a minute the problem occurs again.Any sugggestios?? Can you run with the MAF disconnected .\Advice would be greatly received!

Title: Re: 1997 Mk3 MAF air sensor
Post by: Seanl on 20 November 2011, 17:45

When was the air filter last changed? Running with MAF disconnected will make it cut out eventually. Sounds like its struggling for air with symptoms your describing.

Title: Re: 1997 Mk3 MAF air sensor
Post by: cedar on 20 November 2011, 18:21

The filter isn't that old, perhaps 3 months, and it still looks clean, is not a genuine VW one though. The car pulls okay at high revs which is the opposite to most other posts with this problem. It's not vastly over rich, the plugs are a chocolate brown colour. Up to about 45mph it feels uncomfortable, above that it smooths out and it is using a fair bit of fuel, more than it used to.

Title: Re: 1997 Mk3 MAF air sensor
Post by: gti gaz on 20 November 2011, 19:22

i have a boosch unit off a 97 came with a enguine i baught as a spare am also in cornwall if any use ten sheats in st aufall if any good pm me
chears

Title: Re: 1997 Mk3 MAF air sensor
Post by: Wayne on 20 November 2011, 21:05

Quote from: cedar on 20 November 2011, 17:27

Tried 3 MAFS now but still runs rich and hunting on idle,  if we disconnect the MAF it idles OK . If we reconnect, after a minute the problem occurs again.Any sugggestios?? Can you run with the MAF disconnected .\Advice would be greatly received!

Sounds like you need a new maf, not a wise move to run with it not connected.

Title: Re: 1997 Mk3 MAF air sensor
Post by: javalin on 21 November 2011, 16:05

>Sounds like you need a new maf, not a wise move to run with it not connected.
eye.

No way to know condition / accuracy of a second hand unit.

James