Wondering if I have to replace a MAF for my 1999 156 2.5 V6
I have the F 00C 2G2 030 sensor ( 0 280 218 019 )
I don't have Alfadiag, so testing with multimeter
Signal out is measuring 1.03V at idle, but 1.07 V at 4000 rpm. I'd expected to measure between 1 and 5V, which is sort of confirmed in the HFM5 document here.
However, I am still not 100% sure that the MAF is faulty just going by the reading.
I have had trouble with the throttle link potentiometer, the problem started when hitting a bump, the engine management would light and go into limp mode.
Resetting the ECU would solve the problem for a while. I put up with this for a time, and problem seemed to go away after cleaning the throttle wiring connector under the passengers footwell
After a further 3-4k miles , the car started to misfire and became very jumpy especially when cold. I was leaving the car standing for a while when this started to happen ( this took 2 years, I did not use it much )
When the engine came up to temperature it was a lot better. There was no engine management light on when it was misfiring, but the engine would not go above 4000 rpm.
It was impossible to drive like this, and something was seriously wrong, more than you would normally get with just a faulty MAF sensor.
Anyway, I had read that the throttle assemblies on the Alfas could be unreliable, so decided to investigate the throttle body. There was a small amount of carbon around the butterfly valve but nothing major.
One thing that did not look right, the butterfly valve did not seem to open much, even when revving up to 4000 revs, maximum 1 cm opening from the base of the valve and the body.
Perhaps this is normal ?
I opened the unit and inspected the carbon wiper track ( I wish I'd taken a photo ), one thing I noticed was how thin and delicate the wiper is, it looked extremely dry and worn. It's a good thing they don't put parts like this in aeroplanes.
I thought the problem could not get any worse, so I decided to wipe the track gently with cotton wool and some electrical contact cleaner. Put it back together, what a difference, the misfire had gone and revving past 4k rpm was fine and power like I remembered when I bought it 9 years earlier. I initially thought my problems were gone, but then I noticed that the engine management light was on. Now with hindsight, I realise it would have been better to do one thing at a time, but when I dismantled the throttle assembly, I cleaned the MAF at the same time with IPA.
My question is, if the throttle assembly is not opening fully, could this be affecting the airflow and affect the reading I'm getting on the MAF signal output ?
In much the same way, could a blocked air filter affect the reading of the MAF? I did notice a few cracks in the intake hose, I've managed to repair this so it's air tight now, which is how I took the readings. I guess I should get the fault codes read to see if I made the sensor worse by cleaning, the other thing I'm wondering is if by opening the throttle body it has raised a code that needs to be cleared in the ECU. I've already had the battery off for 45 minutes and reset the throttle but the light is still on. It runs so much better since wiping the contacts, but the idle is hunting abnormally when the engine comes up to temperature.
I found a German company that is offering a 2 year guarantee ( 120.000km ) on their MAFs. Price is 47 Euros ( postage may be extra )
Luftmassenmesser - Motor - ALFA ROMEO, FIAT, LANCIA- Master-Sport-Shop
Click the British flag if it loads up in German
I hope that this is not another rebadged Chinese offering that they are distributing, but they claim to design and manufacture parts for the auto industry.
Anyone heard of Master-Sport Automobiltechnik or tried their MAF sensors ?
I notice their sensors are sold from this supplier.
ww.osm.lt/index.php%3FproductID%3D283&prev=/search%3Fq%3DF00 C2G2030%26hl%3Den%26sa%3DN%26start%3D10&rurl=trans late.googl e.com
I'm reluctant to use the Bosch replacement, due to the numerous reported failures. Is the Pierburg the best bet ? Would appreciate greatly any response.