Hello, I have a 1995 camero z28. I have a check engine light, and i was able to scan the car by jumping the cables to the obd 1 port on my scanner. I pulled up a DTC 51 code which i looked up and it showed PROM Error. So i got a new computer for the 1995, and now the PROM error code is gone. But now the code that i have is DTC 46 Fuel Enable Fail, i did some research and it says I should by pass the Vats system. I bypasses that system, and still i have the fuel code. I was wondering if i would have to get my computer reprogrammed to the car. What are your thoughts?

 

DTC 46 sets when the PCM does not receive the 50Hz fuel enable system from the theft deterrent module, and shuts down the injectors. That can occur if the key resistor reading is missing or incorrect, or if the theft deterrent module fails. How did you bypass the PASS-Key II (VATS) security system…. using a resistor or using a 50Hz signal generator bypass at the theft deterrent module?

4th Gen LT1 F-Body Tech-PassKey/VATS

PS: “Camaro”

 

Yes, First i used the 15 resistors and bypassed it that way, but that didn’t fix it. So i bought the gm bypass off amazon. That still doesn’t work. The car still runs and drives, but what’s weird is that when the car hits around 190 degrees the check engine turns off and no more codes until the car is cool again. I replaced all temperature sensors.

 

When coolant temperature hits 190-deg on the dash gauge or 190-deg in the PCM?

Did the seller program the PCM for your specific year and transmission? There are subtle differences with the 4L60E transmission between 94 and 95. Not that it should cause your problems. Would cause other problems. Was this a new or a refurbished PCM?

Another random thought…. what scanner are you using? There is a model sold by Equus and also by Innova that has an incorrect LT1 data base, and typically returns a false list of seven codes, that includes DTC 51 and several codes that don’t even exist on an LT1.

Another path to troubleshooting the PCM would be a data log using Scan9495:

https://www.camaroz28.com/forums/com...95-lt1-874306/

 

When the gauge hits 190 or when it’s just a warm day. The car on a cold start has the fans running, but then turns off when the engine light stops. I got the PCM from pick and pull, it was for the same year i’m not sure if it was the automatic or not. The scanner i am using is the Innova 3120, which i had to set the year to a 1992, and jump the cables because there is the 16 pin port for my ob1 system. Is it possible that I’ve been getting the wrong code or just some random codes out of this scanner? If so, what scanner should I use?

 

The Innova 3120 has known problems for LT1 use. Your original PCM was probably fine, since they rarely fail. OBD1 scanners are hard to find, but there are some like the Actron 9185 9190 and 9690 that do 1 and 2. A laptop + cable and free software like scan9495 would be a good thing to have and highly recommended for any future diagnostics.

https://www.camaroz28.com/forums/gen...m-prob-883858/

 

Will the Tech 2 scanner work? I just tried the usb scanner to the computer and it wouldn’t connect. Can you recommend any other scanners that are available to buy. Is it possible to change the obd 2 port back to obd 1 port, since GM decided they didn’t want owners to be able to scan their cars.

 

The author of Scan9495 has successfully used a relatively cheap Chinese clone of the Tech-2 to read the 94-95 OBD-2 PCM. Requires an OBD-1 adapter and program cartridge. The 94/95 PCM is just basic OBD-1. I don’t know if the Tech-2 requires a 12 volt pin in the data link connector (DLC). The 94 12-pin DLC does not have a 12 volt pin. But the 95 16-pin DLC does have a 12 volt pin.

Should be easy to rewire a 12-pin DLC on your 95. Look at the DLC wiring diagrams on the Shoebox site:

http://shbox.com/1/DLC_wiring.jpg

 

Have you considered Scan9495, mentioned earlier? Free download, just buy ready made cable specifically for the 95:

https://www.camaroz28.com/forums/com...95-lt1-874306/

OBD Diagnostics