P38A MAF woes
- Thread starter cornishboater
- Start date
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In that case it's easier. Pin-1 = 12V, Pin-3 = Ground, and Pin-2 is the output to the ECU.
The description in RAVE is not quite correct, because the IAT is in the air-filter housing. The attached LR System doc has the correct description on 4th page.
MAF voltage should be about 1.4V at idle. (see P41 in "GEMS by Poole")
The description in RAVE is not quite correct, because the IAT is in the air-filter housing. The attached LR System doc has the correct description on 4th page.
MAF voltage should be about 1.4V at idle. (see P41 in "GEMS by Poole")
Only use a gems maf, and better 2nd hand oem than a new one which is supposed to do the same job. Re your screenshots...in pic1 there shd have been air flow, i guess the engine was off. Probably unconnected, but your idle ref voltage is quite high...using Write settings ( as in one of ur pics) you can write it to 0.625V. Current air flow at 32 was quite high for idle. Pls be aware that adaptive settings only learn above min tank level, not sure if 1/4 or 1/2. IAT temp i looked at it in detail in the past...v8s all read wrong ( or nano does), but doesn't seem to do much ( I have put additional resistance in line on mine to get better temp reading) so that is a distraction. Poole by Morgan and lucas gems nanocom guide are your best refs. I will probably be in Corfe C next weekend if you want to try a "known good" maf off mine. Cd be worth removing/ cleaning the iacv and the ports on the throttle body. Leave the tps in place
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cornishboater
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Thanks guys, there is something to get on with then 
cornishboater
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Many thanks, lotsa info to get on with there, the engine was idling on the old MAF for all screen shots, odd about the airflow bit, I did wonder but I am not au fait with using engine diagnostics so I wouldn't fully know what I am looking at!
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Also check that GEMS is set for the correct engine size. 2nd screen in settings menu.
Once you get the settings in the right ballpark, you should do some drive cycles to train the ECU.
Once you get the settings in the right ballpark, you should do some drive cycles to train the ECU.
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Those short fuel trims are really low
