Differences between 94 and 95 programming
08-02-2015, 06:33 PM
#1
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Differences between 94 and 95 programming
I've been trying to figure out the differences in programming between these 2 years.
When I have a 94 tune loaded into the car, stock or not, everything checks out good. But when I have a 95 tune in it, it always throws a DTC43 knock sensor error.
With the 94 tune, I show I get a little knock and pulls timing accordingly so I know it is working. 95 files show that the knock sensor is non functional.
I know on OBD2 cars, the knock sensors were different, but this is the original knock sensor from 94.
Any ideas? I'm trying to use a 95 program as it uses come of the Class 2 data as on OBD2 cars.
My car is a Frankenstein right now. I have a 99 Camaro body wiring harness and the under hood harness. I get all kinds of errors due to no Class 2 and was curious if I could get the Class 2 to work on the OBD1 setup. The plan in the future is to drop a 6.0 I have sitting in the corner, but this is fun for me trying to get this to work. I could also do the swap where you use an LS1 PCM, but that's more than I want to spend.
When I have a 94 tune loaded into the car, stock or not, everything checks out good. But when I have a 95 tune in it, it always throws a DTC43 knock sensor error.
With the 94 tune, I show I get a little knock and pulls timing accordingly so I know it is working. 95 files show that the knock sensor is non functional.
I know on OBD2 cars, the knock sensors were different, but this is the original knock sensor from 94.
Any ideas? I'm trying to use a 95 program as it uses come of the Class 2 data as on OBD2 cars.
My car is a Frankenstein right now. I have a 99 Camaro body wiring harness and the under hood harness. I get all kinds of errors due to no Class 2 and was curious if I could get the Class 2 to work on the OBD1 setup. The plan in the future is to drop a 6.0 I have sitting in the corner, but this is fun for me trying to get this to work. I could also do the swap where you use an LS1 PCM, but that's more than I want to spend.
08-08-2015, 10:09 AM
#2
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Re: Differences between 94 and 95 programming
I believe the "Class 2" data was added to what GM (or somebody) called OBD-1.5. But that was only used in the Y-Body LT1 PCM. To my knowledge it was not used in the F-Body. Logically, it would appear that the 95 F-Body was supposed to get OBD-1.5, hence the 16-pin ALDL connector. But it was never actually installed.
As far as I know, the part # for the 94 and 95 F-Body PCM's is the same (16188051). The Y-Body uses a different part # (16181333). The only significant difference I can think of between the 94 and 95 F-Body programming would be the use of pulse width modulation for the 95 A4 converter lockup, as opposed to the switched lockup in the 94.
DTC 43 sets when the PCM does not see a value between 0.78 - 4.1 Volts on the circuit (94 manual, I don't have the 95 manual. Maybe Rob/Shoebox can comment). You indicate that you only get the code with the 95 program, and that the 95 program indicates the knock sensor is non functional. I would think that it is possible to program the knock sensor out by altering how it responds to the knock signal, but that might not disable the diagnostic.
As far as I know, the part # for the 94 and 95 F-Body PCM's is the same (16188051). The Y-Body uses a different part # (16181333). The only significant difference I can think of between the 94 and 95 F-Body programming would be the use of pulse width modulation for the 95 A4 converter lockup, as opposed to the switched lockup in the 94.
DTC 43 sets when the PCM does not see a value between 0.78 - 4.1 Volts on the circuit (94 manual, I don't have the 95 manual. Maybe Rob/Shoebox can comment). You indicate that you only get the code with the 95 program, and that the 95 program indicates the knock sensor is non functional. I would think that it is possible to program the knock sensor out by altering how it responds to the knock signal, but that might not disable the diagnostic.
08-10-2015, 12:42 AM
#3
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Re: Differences between 94 and 95 programming
I tried to disable the KR, but as you said the code is still present.
The.bin files I am using are from a 95 T/A. I have tried others as well with the same result. Only 94 .bin files do not throw a code.
You mentioned a difference in the Corvette and F Body PCM parts numbers. Is there some kind of difference? Did they have a different knock module in the car? I have an LT4 module somewhere, but it doesn't make a difference.
Lastly, is there any difference in the Corvette programming compared to the F-Body?
All of this come down to the car is a 94. I have a 2001 body harness and engine harness in the car. Years ago, I had a donor car and was going to convert the car over to LSX setup. I never got around to it. I still like driving the car with the LT1 in it, but all of the lights on the dash are driving me crazy! With the help of the Tech 2, I've been able to get everything narrowed down and most of the lights off, but there are a few that want Class 2 data to go away. Again, not expecting it to, but would be cool of it worked. I've managed to get the 98+ ABS block to work and the airbag module. The traction control won't work because of the TPS signal needed. When I tie into the TPS directly, it throws the voltage off and says the throttle is resting at 16%. Maybe a diode on there would correct it.
My next experiment is going to be to put a 97-04 Corvette dual climate module in my 2000 Silverado!
The.bin files I am using are from a 95 T/A. I have tried others as well with the same result. Only 94 .bin files do not throw a code.
You mentioned a difference in the Corvette and F Body PCM parts numbers. Is there some kind of difference? Did they have a different knock module in the car? I have an LT4 module somewhere, but it doesn't make a difference.
Lastly, is there any difference in the Corvette programming compared to the F-Body?
All of this come down to the car is a 94. I have a 2001 body harness and engine harness in the car. Years ago, I had a donor car and was going to convert the car over to LSX setup. I never got around to it. I still like driving the car with the LT1 in it, but all of the lights on the dash are driving me crazy! With the help of the Tech 2, I've been able to get everything narrowed down and most of the lights off, but there are a few that want Class 2 data to go away. Again, not expecting it to, but would be cool of it worked. I've managed to get the 98+ ABS block to work and the airbag module. The traction control won't work because of the TPS signal needed. When I tie into the TPS directly, it throws the voltage off and says the throttle is resting at 16%. Maybe a diode on there would correct it.
My next experiment is going to be to put a 97-04 Corvette dual climate module in my 2000 Silverado!
08-10-2015, 07:02 AM
#4
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Re: Differences between 94 and 95 programming
How are you attempting to disable the knock sensor? If you are just changing the max allowable retard, and the attack and decay rates, it's probably not disabling the diagnostic. I am not an LT1 factory PCM programmer, so don't give any special weight to anything I say about programming. I switched to an aftermarket ECU 15 years ago.
Have no idea about the Y-Body programming. I do have the factory diagrams for the Y-Body, by year. I'll look and see if there are any additional ASR or ride control interfaces.
Have no idea about the Y-Body programming. I do have the factory diagrams for the Y-Body, by year. I'll look and see if there are any additional ASR or ride control interfaces.
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