Today a 98 GTP came over for a tune. He said he got a dyno tune, cost him $700. After the tune he called them back and said the cars not running right. That will cost you another $300. He wasn't happy about that. So I took a look.
Why is the timing so low? OK, let'* get started here, unplug the MAF and lets do a VE tune.
Holy cow, that needs some work.
After adjusting the VE table the first thing he said is, wow, it'* running better already.
So I adjust the VE table and then check the MAF table. It seems kind of good but rather lean on the WOT area.
So I pull up the PE table, odd, why is everything at zero? And why is the commanded AFR at 14.1:1? That'* not right at all. So I grab my tables and copy them over to his and add 4* of timing. Then go out again.
Wow, the timing looks much better, the AFR is much better. The car pulls like crazy, no KR. He'* really happy now.
He said the guy that tuned his car last time was canned because he messed up a few cars. Looks like that guy was a real clown. He zeroed out several tables and never put them back. A over site like that could have wrecked a engine. It'* a good thing he watches his car so close. He knew something was wrong right away and didn't get on it to hard. All in all, a good time tuning.