Fuel issues

[Guest]

Hey ducattiman you ever consider a wideband 02 to see if you really are running lean and not speculate at the idea? Probably not

[sharkey]

anyone who knows about engine tuning knows backfiring out the intake means lean, and dead lean at that. its not speculation, its proven fact. i just got my megasquirt on my car, and when it was lean and i stepped on it, it backfired out the intake and the a/f gauge was showing 19.5:1.

[Guest]

It doesn't always mean it is lean though. There are other factors that contribute to backfiring.

[Ducatiman]

hey shaun,, are white plugs with blue electrods a sine of running lean??? Trust me their no vacuum leaks anywhere the wires are on corectly the timming is fine it needs more fuel i cranked up the fuel psi to 55 lbs it seemed to help a little but its still not right

[Ducatiman]

Does anybody have ECM pinouts for a 93 grand prix?

[bszopi]

http://60degreev6.com/showthread.php?t=25020

Either the 92 or 94 DOHC should be similar to the 93 GP. I'm just not sure about the pinout differences between a DOHC and MPFI. And I'm not sure which you are looking for...

[Guest]

hey shaun,, are white plugs with blue electrods a sine of running lean??? Trust me their no vacuum leaks anywhere the wires are on corectly the timming is fine it needs more fuel i cranked up the fuel psi to 55 lbs it seemed to help a little but its still not right

Maybe its a sign of too hot of a heat range of plug. Did you think of that? Probably not.

so you think its lean. Do you know how lean? No you don't. Because you don't have a wideband.

[Ducatiman]

the heat range of the plugs are not on the hot side.............

[Ducatiman]

shaun I went from a stock motor to a built motor and the computer is still metering the same amount of fuel for a stock motor

[AaronGTR]

anyone who knows about engine tuning knows backfiring out the intake means lean, and dead lean at that. its not speculation, its proven fact. i just got my megasquirt on my car, and when it was lean and i stepped on it, it backfired out the intake and the a/f gauge was showing 19.5:1.

Ducatiman, I'd have to agree with you and everyone else about the lean issue. Given the amount of work done to the engine and all the evidence I think it's pretty clear cut. The megasquirt would definitely be a cost effective option compared to the haltech. A wideband might not be a bad idea still for fine tuning eventually but you shouldn't need it to correct the majority of the problem and get a rough tune that it will run and drive on.

I'd help you out with the tuning myself but my tuner only works on obd2 3400's. I do have a innovate LM-1 wideband though if you wanted to use it sometime to check the AFR after you get some tuning done... or maybe you'll end up getting one yourself since they aren't very expensive anymore. Either way I'd like to see the car when it's running right again. I live in macomb county so I can't be far from you.

[Ducatiman]

well im in south lyon the other prject im working on is a dune buggy with a 3.1 liter out of a 93 grand prix and im using the 002 bus trans but im still waiting for my adapter plate and flyweel from kenedy enginering (should have about 9lbs per hp should be fun)