L99 electrical problems
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L99 electrical problems
Hi
I got a L99 from 1996, little brother to the LT1, in my Rat rod.
A complete new wiring harness and an updated PCM.
The problems I have is.
1. The gearbox downshifted from 4 to second gear just like that last summer!!
2. I can't get the OBD2 reader to work, when I connect it and turn on igniton the fuelpump starts to run??
The electrical system was for a 94-95 Camaro, but I couldn't get any blink codes from that either so I did rebuild it to OBD2..
I hope you have som info that iI can use
regards Peo
I haven't got a clue were to start to check the system
I got a L99 from 1996, little brother to the LT1, in my Rat rod.
A complete new wiring harness and an updated PCM.
The problems I have is.
1. The gearbox downshifted from 4 to second gear just like that last summer!!
2. I can't get the OBD2 reader to work, when I connect it and turn on igniton the fuelpump starts to run??
The electrical system was for a 94-95 Camaro, but I couldn't get any blink codes from that either so I did rebuild it to OBD2..
I hope you have som info that iI can use
regards Peo
I haven't got a clue were to start to check the system
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Re: L99 electrical problems
Hi
I got a L99 from 1996, little brother to the LT1, in my Rat rod.
A complete new wiring harness and an updated PCM.
The problems I have is.
1. The gearbox downshifted from 4 to second gear just like that last summer!!
2. I can't get the OBD2 reader to work, when I connect it and turn on igniton the fuelpump starts to run??
The electrical system was for a 94-95 Camaro, but I couldn't get any blink codes from that either so I did rebuild it to OBD2..
I hope you have som info that iI can use
regards Peo
I haven't got a clue were to start to check the system
I got a L99 from 1996, little brother to the LT1, in my Rat rod.
A complete new wiring harness and an updated PCM.
The problems I have is.
1. The gearbox downshifted from 4 to second gear just like that last summer!!
2. I can't get the OBD2 reader to work, when I connect it and turn on igniton the fuelpump starts to run??
The electrical system was for a 94-95 Camaro, but I couldn't get any blink codes from that either so I did rebuild it to OBD2..
I hope you have som info that iI can use
regards Peo
I haven't got a clue were to start to check the system
What Model and Year Transmission do you have?
I am glad to see someone that actually has the little 4.3L V8 L99 Engine.
Are you using an original L99 PCM?
Are you using the original L99 Power-Train Wiring Harnesses?
What does: "The gearbox downshifted from 4 to second gear just like that last summer" mean?
That was your 1st Post... how are we supposed to know what happened last summer?
Please clarify why a 4th to 2nd Down-Shift is an issue... depending on Vehicle Speed, many Automatic Overdrive Transmissions are supposed to do this.
The 1994 Camaro Power-Train and Interior Wiring pre-date OBDII.
What Wiring did you exactly use?
How did you modify it?
Changing from Pre-OBDII to OBDII Wiring Harnesses is rather involved...
You are going to have to go in to details here in order to help you diagnose your issues.
Start with all of that...
More questions to come.
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