Steve_S3 Posted August 22, 2005 Author Report Share Posted August 22, 2005 From Motormania - one of those car accessory chains. It was just Holts Carb Cleaner. I've heard that you could use Isopropyl Alcohol, but I think that's more difficult to get hold of. Link to comment Share on other sites More sharing options...
neo283 Posted August 22, 2005 Report Share Posted August 22, 2005 I had the exact same prblem on my MAF. Wasn't as lucky as you with the cleaning off though. Did you use a non-oil based cleaner, as I thought that if you sprayed oil based, it would leave a film and cause the problem to come back? I used K&N filter cleaner. JimBob, you can get a torx screw head from most Halfords-like places. I got mine in a box set, £10 for a 40 piece kit of screw heads. Just make sure that you get the correct bit, the one you need has a receiver hole in the middle of the star pattern. If replacing the MAF, it comes as a section of intake pipework & the sensor, which required a sort of clamp to remove the metal hose clip. Link to comment Share on other sites More sharing options...
Jimbob_S3 Posted August 22, 2005 Report Share Posted August 22, 2005 Thanks, I'll get the stuff and have a look when I get chance. Had a new MAF 2 months ago, was good for a while, but got exactly the same problem again as when it was broke... i.e. poor performance and MPG at 32 again instead of about 26... So i might try cleaning it. You never know.. Link to comment Share on other sites More sharing options...
neo283 Posted August 22, 2005 Report Share Posted August 22, 2005 Goes without saying, be chuffin careful when you clean it off! The guys suggested I use cotton wool buds on the sensor as the metal wire part is particularly fragile. Mind you, if you're getting 32mpg out of it as opposed to 26, perhaps you could run it this way for a while until you save enough money to buy a new one?! Wont take long at todays prices! (Ahem, not that I want to open this debate again) Seriously though, if you're running a lean mix, tends to point to the MAF. Link to comment Share on other sites More sharing options...
Paul Posted August 22, 2005 Report Share Posted August 22, 2005 running lean ie good MPG is not good and can do just as much damage as too much. Dont forget a knackered maf, in extreme cases can cause engine failure. Link to comment Share on other sites More sharing options...
Jimbob_S3 Posted August 24, 2005 Report Share Posted August 24, 2005 Ok, didnt have the stuff to unplug MAF, but plugged car into VAG COM. No faults found on engine, surprisingly. Unclipped electrical connector from MAF, gave connector quick clean and reconnected. Drove car, woosh, power returned. Reset trip, done 50 miles of my standard journey. MPG returned to my usual 26... instead of 30+ Good.! Faulty/dirty connection ? Time will tell. Link to comment Share on other sites More sharing options...
Steve_S3 Posted August 24, 2005 Author Report Share Posted August 24, 2005 Amazing!! Something else to keep an eye on where the MAF is concerned. MAF faults won't always throw up a VAG fault - mine didn't. It was the tuner who found that it was 0.2v out from the default of 5.0v.... Perhaps we should all wrap the MAF in a good thickness of cotton wool.....seems it's very "fragile" Link to comment Share on other sites More sharing options...
Paul Posted August 24, 2005 Report Share Posted August 24, 2005 Mafs are notorious for not throwing codes except in its last dying moments. Not sure where they got the voltages from, its a new one on me. Plausable but not one ive heard. Early Mafs on other Audis were known to be so delicate if you slammed a car door they could feck up. They go through a heating stage i believe (or used to) to burn off the crud they have picked up. Im not sure if this still applies, but generally they are more robust than they used to be. Link to comment Share on other sites More sharing options...
robintegra Posted August 24, 2005 Report Share Posted August 24, 2005 Right i think im going to get some carb cleaner and clean the - *Maf *N249 Valve *Also around the inlet to Turbo Rob Link to comment Share on other sites More sharing options...
neo283 Posted August 25, 2005 Report Share Posted August 25, 2005 From what I was told when experiencing the same problems, the fluctuating voltage is usually measured across the hot plate as Paul-S3 suggests. The car is set up to send an electrical spike to the plate on the MAF when the ignition is turned off to burn off crud. There is a relay somewhere near the front end of the motor which controls this spike, if this fecks up and doesn't send enough voltage to heat the plate to its full potential, zero crud burning will occur and the MAF will colect a film of oil/residue (especially from an oiled K&N or similar air filter eliment), and take incorrect readings. Some people stay away from K&N because if this problem. Again, like Paul-S3 says, they're notoriously fragile! Link to comment Share on other sites More sharing options...
Steve_S3 Posted August 25, 2005 Author Report Share Posted August 25, 2005 The controlling relay would possibly explain why some people have to change their MAFs after only a few months. Perhaps a change of relay at the same time would fix the problem..... Link to comment Share on other sites More sharing options...
neo283 Posted August 25, 2005 Report Share Posted August 25, 2005 This was flagged up on a different forum about a month ago. Funnily enough, it was the guys mate who identified the possibility that the relay wasn't working and checked the current accordingly. Apparently even the stealers didn't identify the problem and after 3 new MAFs he got the hump. Had my new MAF a month now, getting worried that I sould have had the relay sorted or at least checked, but I don't know where the feck it is! Link to comment Share on other sites More sharing options...
Jimbob_S3 Posted August 25, 2005 Report Share Posted August 25, 2005 Anyone now where the relay is specifically or how to change it? Wouldn't mind changing mine, because knowing my luck that will break too.... Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now