PDA

View Full Version : Strange MAF&MAP tune issue...



dc_justin
September 30th, 2006, 05:20 PM
I'm running into a strange issue here with my truck running COS3, OS version 03190003.

I've completed my VE tune without too many problems that can't be explained by the piss-poor quality of CA gas.
I've re-enabled the MAF, with B0120 set to 400rpm so that the VE table is not having any effect on my fueling. MAF looks good for the most part.

Adjust B0120 back to the stock 4000rpms and the fun begins.

Both MAF and SD individually will correctly measure the air mass, but combined I'm seeing anywhere from 10-25% less fuel than needed... CYLAIR_DMA looks to be pegging out at the 105kPa column's value, while both the calculated MAF cylair value an dyncylair_dma show significantly higher airflow. I've tried starting from scratch again by re-flashing the full OS in with no luck.

Has anybody run into any problems with this particular OS version? In addition to this, I'm seeing zero effect from the OL ECT Multiplier table, which causes the truck to run very lean with initial throttle opening in SD mode...

dc_justin
October 2nd, 2006, 04:45 AM
Tried a different COS calibration, 03150003, still had the same issue. I've checked, double-checked and triple-checked the entire tune over and am stumped...