Agt. Orange

I just swapped a LS1 into a 97 firebird, changed everything and all harnesses. everythng works except the car idles crappy dies at times and trips the code 1638 for 5 volt reference? what does this mean?


car has ported heads and a 224/224 .581/.581 cam installed also.

it also has a misfire detected, and the AC pressure low (havnt filled it yet)

Im also using HP Tuner.

thanks.

Black02SS

iTrader: (36)

Sounds like the code is a alternator issue. If you want to send the tune, I'll glady check it out. What year of tune are you using along with the year of PCM?

Agt. Orange

it is a 2000 LS1 but the harness and pcm is from a 99, i have a tune w/ the ve tables adjusted for a cam, and also tried the stock tune. doesnt make a diff. we took it for a drive, it kinda coughs and mis fires and has absolutley no power.
i'll look into the alternator. could it be something stupid that was over looked? we've double checked everything and all seems to be hooked up and working....that we know of.

Black02SS

iTrader: (36)

Is that the only code that it is throwing? I know it may sound stupid, but did you check the plugs and wires? Where is the misfire coming from?

Agt. Orange

misfire is unknown. it runs fine when its in neutral. it also has a 3800 stall and nothing tuned for it. while driving it stutters and wants to die when you let off the gas. plugs are new, wires seem in good cond. its not a steady mis. very eratic.

codes- engine misfire detected, AC low, and the 5v reference circuit 2
no other ones.

Agt. Orange

is there a code that would detect if the fuel pump was not working right? a low pressure code or anything?

Black02SS

iTrader: (36)

Can you hop on AIM real fast?

Agt. Orange

yep im on.