07-01-2013, 08:52 PM
New MAF from dealers are £110.96 (1920 7S) and there £80.40 from ECP (434735120). I bought two for £100 and something when ECP had there 31% off sometime last year.
The hotwire on the MAF or the two "wires" are glass coated with a thin layer of copper.
My thoughts on failure are,
1) Open circuit failures are most likely broken wire or wires and most likely down to vibration or shock that have broken the fragile wire or wires.
2) Incorrect measurements are down to contamination. I think most contamination is most likely from the crankcase breather pipe on standard cars. Diesel engines have a lot higher crankcase pressures down to the higher compression ratio in the cylinders and have more blow by pressurising the crankcase so the oil mist in the system coats the MAF and builds up causing it to miss read. Yes the MAF runs a cleaning cycle but after some time the burnt oil starts forming carbon on the elements or "wires" and this build up is the reason of the miss reading.
I think MAF's usually read incorrectly more often then failing by broken wires.
Now these are just my thoughts on why MAF's fail and I have no proof of my theory just yet but it would be interested to see how long a MAF lasts on a car with an oil catch tank so there is no oil mist coming from the crankcase to cover the MAF?
You can manually clean a MAF but care must be taken in not damaging the element and if you do clean it yourself it's a good idea to check it's all ok with pp2000 after as if you damage any of the two elements it won't bring the ELM light up, it'll just log a silent code in the ECU. The cleaning solution mustn't leave any residue on the element as this will cause incorrect reading. Switch cleaner is good to get the carbon off but some leave a lubricant so best to give it a blast with IPA after but it is really easy to damage the element and not know until it's too late.
I've tried cleaning them with an ultra sonic cleaner but even that damages the elements.
The hotwire on the MAF or the two "wires" are glass coated with a thin layer of copper.
My thoughts on failure are,
1) Open circuit failures are most likely broken wire or wires and most likely down to vibration or shock that have broken the fragile wire or wires.
2) Incorrect measurements are down to contamination. I think most contamination is most likely from the crankcase breather pipe on standard cars. Diesel engines have a lot higher crankcase pressures down to the higher compression ratio in the cylinders and have more blow by pressurising the crankcase so the oil mist in the system coats the MAF and builds up causing it to miss read. Yes the MAF runs a cleaning cycle but after some time the burnt oil starts forming carbon on the elements or "wires" and this build up is the reason of the miss reading.
I think MAF's usually read incorrectly more often then failing by broken wires.
Now these are just my thoughts on why MAF's fail and I have no proof of my theory just yet but it would be interested to see how long a MAF lasts on a car with an oil catch tank so there is no oil mist coming from the crankcase to cover the MAF?
You can manually clean a MAF but care must be taken in not damaging the element and if you do clean it yourself it's a good idea to check it's all ok with pp2000 after as if you damage any of the two elements it won't bring the ELM light up, it'll just log a silent code in the ECU. The cleaning solution mustn't leave any residue on the element as this will cause incorrect reading. Switch cleaner is good to get the carbon off but some leave a lubricant so best to give it a blast with IPA after but it is really easy to damage the element and not know until it's too late.
I've tried cleaning them with an ultra sonic cleaner but even that damages the elements.
