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dvx
July 5th, 2008, 07:30 AM
I have done AutoVE multiple times, and all the ben's are within +/- .01. My AFR was good after returning to closed loop except for lean spikes when coming to a stop (I think when it downshifts) and at idle it was a bit lean. So today I did AutoVE again, and when I was finished I attempted to calibrate the MAF using the ben Map in v 7.5. But I'm a little unclear on how to do this. I left my AutoVE tune with the latest VE table in, and plugged the MAF back in, leaving it in open loop. After logging a bit, the MAF ben MAP showed I needed to adjust down low (where it's normally lean), so I did the copy/paste + multiply. Then I repeated the process, and the ben MAP is closer but still shows I need to adjust up to 5% in one cell down low. But at this point my AFR is very close and I think it might be best to leave it alone. Am I doing something wrong or do I just need to keep going?

Thanks for any help.

Dave

dvx
July 5th, 2008, 07:34 AM
mods below

joecar
July 5th, 2008, 08:08 AM
After plugging in the MAF, reenable it by setting the fail limits back to stock.

Then clear the DTC's and verify that P0101, P0102, P0103 don't come back on.

dvx
July 5th, 2008, 08:37 AM
Thanks joecar. I didn't do that. I've been reading the stickies here and found the MAF adjustments thread. Very interesting. I have been trying to get all the surge out of my car by working with the timing, cracker and follower tables. But no matter what I do it's still there at part throttle, light load, and when coming to a stop. Which is why I have reverted back to fueling. Even though it seemed correct, running in open loop without the maf, it's dead on and I have no surging. The car runs great. I suspect the surging is going to return once I re-enable the MAF and return to closed loop. If this is the case, what do you suggest I do? This is a street car and I don't want my tune to change with the weather.