MAF and IAT calibration

[68problemchild]

Hey guys. I have a custom setup. Why is it when I put stock parameters in for my maf, my IAT goes way out of whack at key before start?

If you find a stock maf in a known tune, can you be assured the table is correct? If not, is there a way to calibrate it?

Thanks!!

[Taz]

Swingtan’s VVE Adjustment Tutorial (previously posted) can be used to calibrate VE and MAF values - directly applicable to your E38 ECM and L76 tune. The MAF adjustment setup is covered on page 15 of the document - uses the same basis technique as the VVE adjustments - described on pages 1 to 14.


Regards,
Taz

[68problemchild]

Working on the swingtan tutorial. Commanded AFR B0141 set to 14.5? Looks like max is 1....."assuming EFI live set to work in AFR"? Does it have another mode?

many thanks!!

Sorry Newbie here.

[swingtan]

Do you have a log of the symptoms?

If the IAT values are OK when the engine is running, I wonder if there is a power issue to the IAT sensor. The sensor its self is just a thermistor, so nothing exciting there. The settings for it are in B0188 and if you really wanted to, you could map out the actual values using a thermometer and a digital multimeter. While I think the whole sensor is pretty water tight, I wouldn't go dropping it in a pot of water to do this though. You could try oil though, but that may have a negative effect on the sensor as well. I'd probably test it by feeding a current through the sensor and using a laser thermometer to read its temp. Use normal Ohm's law taking voltage and current to get resistance at different temps, raise the current to get the sensor hotter... ( Warning, this may fry the sensor if you let it get too hot.... ) Normally though, a stock tune from the car the MAF came from is more than adequate.

RE: B0141, in Tune tool, select <EDIT>-<PROPERTIES>, you can set if EFILive displays in EQ, Lambda or AFR.

Simon

[68problemchild]

Will do. Thanks Simon. I am having serious tranny issues right now so will return to this issue soon.

[alian]

Hey Mate. is your tranny issues only come about since you started playing with the maff???
Ian

[68problemchild]

No. MAF is dialed in but tranny issues were some what resolved by playing with the tranny tune. So maf was unrelated. Taz knows loads more about it than I do. He has been a great help.

Currently putting in a new 9" rear end so all is on hold until this is eliminated as a potential issue. I am having some torque converter issues with slip. 40 year old rear end is shot.