Confused? any suggestions

[black50]

just bought a 90 Gt with a gt-40 crate, I was told the timing was off, so I got it fixed, when I bought the car it was running around 29 pounds of fuel pressure. the timing was set at 10, and was corrected at 14, I changed the spark plugs, and wires, I noticed that cyc. 4 and 8 with running very rich, and as you go to the front of the block the spark plugs were running really lean! everything was running okay after the timing, I was idling around 1k, now I start it up and its loping around 500, and the fuel pressure is around 42-43 pounds

 

[JChalfan]

just bought a 90 Gt with a gt-40 crate, I was told the timing was off, so I got it fixed, when I bought the car it was running around 29 pounds of fuel pressure. the timing was set at 10, and was corrected at 14, I changed the spark plugs, and wires, I noticed that cyc. 4 and 8 with running very rich, and as you go to the front of the block the spark plugs were running really lean! everything was running okay after the timing, I was idling around 1k, now I start it up and its loping around 500, and the fuel pressure is around 42-43 pounds

Did you change the fuel pressure, or did it change itself? 29psi is way too low, should be around 39psi. If you changed the fuel pressure yourself, did you reset the computer after that?

What do you mean by the plugs running really lean, do you mean they were white when you pulled them out?

Were 4 and 8 really carboned up, or soaked with gas?

If you could post a more detailed rundown of your combo, it may help too.

Oh yeah, and of course, pull the codes!

Jeff

 

[Modular2v]

cylinders 4 and 8 are naturally the richest cylinders where 1 and 5 are naturally the leanest

 

[JChalfan]

cylinders 4 and 8 are naturally the richest cylinders where 1 and 5 are naturally the leanest

I know there can be a difference when running a carb, but is this also true with EFI where each cylinder has an injector spraying right into it? I would think they should all be getting the same amount of fuel. I know with a stock intake 1 and 5 don't get the same airflow as the rest...

Jeff

 

[Modular2v]

I know there can be a difference when running a carb, but is this also true with EFI where each cylinder has an injector spraying right into it? I would think they should all be getting the same amount of fuel. I know with a stock intake 1 and 5 don't get the same airflow as the rest...

Jeff

right . . . which is why it runs richer/lean. . . they all are prob getting the same amount of fuel but not the same amount of air