1990mustanggt

Could be possible. My fuel guage stopped working. I just thought I had enough gas in it though. I made it 17 miles down the road after the first time that it started doing this.

FiveLiterRiceEater

if it backfired through your throttle body your timing is probably off, are you positive your distributor isnt 180 off?

FullAuto

Well I don't think you're beyond the computer's limits. I made over 600rwhp with a stock A9P with no chip.

1990mustanggt

If it was 180 out it wouldn't crank at all. It would just spin over and backfire. It's like it loaded up or something.

PRO50SC

W/ all that new gear, the ecm may be having a brain fart. It's not used to running at the capacity it is now. You may have to have chip burned for it.

1990mustanggt

That's what I'm worried about. I don't want to have to spend anymore money right now. Plus the closest place to me is like Alabama or Texas. Long drive to go have a chip burned.

1990mustanggt

I still don't know what's causing this. Are there any other ideas that some of you might have, or had this happen to?

turbostang21

no chip?? please explain[&:] i should be well over 700whp (pump gas) on a mustang dyno when i tune for methanol w/ a stock computer...but i certainly have a chip (sct w/ 4 programs).
1990 i woud check for vacuum leaks, tps voltage, and iac

btw there are cars making over 1000whp on the stock comp. with some sort of tuner