nbays1975

I just got a new GTA and am having a strange problem. Raw fuel is coming out the exhaust pipe. It runs very poorly until it reaches a certain temp and then instantly starts running better (but still rich). The interesting thing is that I just had new exhaust put on. It didn't do this with the old exhaust. However, the old exhaust had a "modified" cat. Completely gutted. The new exhaust has a functional cat. I'm assuming the problem is in the tuning, but I don't know where to look. I Pulled the memcal and there is a chip from FastChip in it. I just ordered my burner and am new to chip burning. I know I'm not going to get the perfect chip right off the bat, but I would like to at least get it to idle and be safe (my bumper caught on fire from the fuel!). Anyway, does this sound like a chip problem, and if so, where do I begin?

I didn't build the engine myself but here are my engine specs as best as I can determine:
The engine is heavily modified 383.
Speed pro forged pistons (10.5:1)
Edelbrock Performer heads
Trick Flow 1.5 roller rockers
Comp Cams hydraulic roller 230/234 528/539 110lsa
Holley Stealthram
30lb Ford SVO injectors
52mm Throttlebody

RBob

iTrader: (1)

Well-l-l, the first thing to do is to stop driving it until you can start with tuning. With that much fuel it will definately ruin the engine.

The second step is to decide which Mask you are going to run, then get a stock(!!) BIN to start with. There is the early '86-'88 $32 mask, and the later '89 $6E mask. Personally I would go with the $6E mask. At a minimum will need to set the injector constant for the larger injectors.

The third step is to get a data logging set up. Will need data logging to see what is going on.

RBob.

{edit: I would also check for mechanical issues. The FPR could be leaking fuel through the diaphragm which can show up in the vacuum line. The FP could be too high. Or an injector or two could be leaking.}

JP86SS

iTrader: (1)

Be certain this is fuel coming out.
Most of the time it is condensation buildup within the mufflers that gets blown out on startup. Some mufflers hold water better than others.
It will stop once the car exhaust is warmed up and dries out.
If you really think its fuel, collect some and get far away from the car and see if it burns. Then you'll know.
Jp

How'd the bumper catch fire back there?
you'd be blowing out flames pretty good I'd imagine.
Better check the fuel pressure too!
The regulator diaphram may be busted and your pulling fuel directly into the intake.
Pull the small vacuum line off of it and see if it is wet or has had fuel in it.
that would do it.

rockit

iTrader: (3)

cars a real firebreather huh? congrats, welcome to the not so exclusive club of gta owners round here, and to another club, thirdgens that don't run right!
"i'm not only the founder, i'm also a member"

i'm sure when you get tuning red'n'gold will chime in, best of luck till then.

oh and rbob and jp are both well recognized around here, you can take pretty much anything they say for fact.

nbays1975

I don't know for sure since I was driving when it happened. My speculation is that raw fuel collected in the tail pipe and when the exhaust got hot enough it ignited. BTW, I'm not driving it right now, no worries. I drove it home after getting the exhaust put on and now its sitting in the garage.
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I'm pretty certain its fuel. I can smell it when I drive. Also, even when it finally warms up and is running good, if I give it too much gas it chokes and my A/F ratio gauge jumps to the right (Rich).