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Discussion Starter #1
I just bought a 97 firebird (3.8 automatic) with 39k miles on it... It has no power, never shifts gears, and the speedo reads alot faster than you're actually going (just like it's in overdrive)...had an error code for the Crank Position Sensor, replaced it and have no ALDL codes now.

Thought it was the tranny, so I replaced it with one that I know is good, but it still does the same thing. Took it to Pontiac, they said the tranny is good, but it thinks it's in 5th gear (it's an automatic...there is no 5th gear...$150 and a major headache later, they suggested parting it out.)

Saw another post where they said they replaced the ECM, but that didn't help... I can't think of anything other than the ECM that has anything to do with the tranny shift points.

Does anyone know if there are 2 ECMs for the firebirds, one for an automatic and the other for a manual? That would explain the 5th gear thing from Pontiac and the tranny always staying in one gear. Pontiac and every local tech I've talked to say the ECMs from automatics and manuals should interchange...if that's true, I'm at a complete loss...
 

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Bowtie or Die!
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636 Posts
Yes there are two differant pcm programs. Your tranny is pcm controlled. Thats not a problem you can get far with by guessing. You need to take it to a reputable shop that has a Tech 2 GM scanner and see whats going on with the shift solinoids etc...There should be a tranny code not all ttrans code will trip the Service light.Yes there most certainly is too differant pcm's for your car. If this car was wrecked and sombody installed a manual trans PCM that would cause all kinds of problems.
 

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Discussion Starter #3
Thanks for the info!

The car wasn't wrecked, the previous owner couldn't get it to run. Said he'd replaced "almost everything" but the service engine light kept coming on. Pulled the code and replaced the Crank Position Sensor, and it started right up... Thought I had a gem for only $1000. I'd bet almost anything he put a used ECM in it which came from a manual...
 

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Bowtie or Die!
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636 Posts
Yes I agree. Thats the first thing I would check. If you took it to be scanned and they said 5th gear prob, thats a dead give away. Still sounds like you got a good deal even if you have to spend a few more. good luck:thumbup:
 

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wind & fire = guides to power
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$1000! Where's the "green with envy" emonicon?

Oh well, I guess this'll have to do> :thumbup:
 

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97 firebird

2.8 s-10 700 will fit that block and your torque converter will fit that early trans, will make car drivable check engine light will still be on. its that or have good electric guy spend time and your money to fix it right. ecm or pcm is where I would check there are many computer repair places out there that for a small charge will test your computer off the car.
 
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