996tt MAF fault

[maxpaul]

I have had a problem with abs and psm lights on when driving hard. Porsche have checked dme codes and have recorded P0103 which is MAF faulty. I have previously replaced this with a Bosch item from Euro Car Parts at £80. Porsche recomend a genuine part at over £200! Am I correct that both items are made by Bosch? Would there be a quality difference between the two sources? I dont want to order the Porsche item and find I still have the problem. The car has been remaped and lights come on at full boost 1.0 to 1.1 bar.
Thanks for any advise

Paul

[Pugley]

Porsche don't make MAF sensors so a genuine Bosch replacement should be OK.

I would be more inclined to see if the level of fueling on boost is beyond the working range of the MAF. Too much unburnt fuel is known to contaminate the membrane within the sensor. (and is also not too good for the CAT)

[maxpaul]

Thanks for the reply
I am assured fueling is all in order and advised fueling is down stream from the MAF so should not cause this problem I also have a K and N filter fitted should I try changing this back to std or may be try a BMC which I understand has less oil treatment.

[Richard Hamilton]

Over-oiling of a K&N or similar filter is a sure-fire way to fry the MAF.

[maxpaul]

Hi Richard yes I agree but never had a problem before the remap do you think the extra boost is now sucking oil from the K an N and is triping the MAF ? What are your thoughts on the Piper, BMC or std ? I like the idea of a freeflowing filter over the std item

[Richard Hamilton]

The panel filters (which I assume you have) are better than the cone filters, but any oiled filter will contaminate the hot film of the MAF if it is over-oiled. I can't see how any of them would flow more air than a standard paper filter unless they were doing a poorer filtration job.

I would have a word with someone with mapping experience, like Ken at 9E, and see what their experiences and recommendations are.

[bobsan]

without going on about aftermarket filters for reams of digital pages and after years of experience, bin the K&N stick with paper.

[996ttalot]

I wouldn't make the assumption that it is the maf. The standard code is 102 iirc hot film thing or something like that - that is normally maf and reflected in low maf figure when tested.

103 is normally a voltage issue with too high a boost reading. I would suggest forget about replacing the maf and concentrate on checking boost leak, Primarily from turbo to intercooler and also at the throttle body. Typically this is triggered aafter 5000 rpm and on full boost. The remap is not the issue as such.

Maf error when on boost is typically boost leak, not faulty maf, and as you said you only replaced the maf recently.

Re filters generally, we fit both k&n and Bmc and I cannot remember an occasion when the maf has gone as a result, and we do a lot of tuning.

Ken

[996ttalot]

Richard Hamilton said:

Over-oiling of a K&N or similar filter is a sure-fire way to fry the MAF.

That is correct Richard. We are careful with how much oil and also make sure that once oiled, that we "dry" the filter to make sure there is no excess etc.

Ken