BigWil

Yah I know, better my PCM than my GF. I have a 94 LT1 and when I plug in the code reader from the part store (key on engine off) I get nothing. Not even the code 12 like it is supposed to. It just sits there with a solid "service engine soon". I would like to get the PCM kit so I can tune it but need to make sure this thing doesn't have a bad PCM before I do.

Any thoughts on how I can diagnose it?

Big Wil

brucer

i thought autozone code readers were for obd2 only, i dont think it'll read obd1

moparman

If the code reader or scan tool is OBDI and it won't connect to the pcm, check the cig lighter fuse to be sure it is good as the port is on the same circuit.

If it is the correct tool and the fuse is good, it is possible the tool is not working properly.

shoebox

You can't use a cheap code reader that only shorts the A and B pins. You need a real scanner.

94CamaroZ28/SSClone

Yes Autozone only has OBD2 not OBD1 for our LT1s.

Injuneer

Shoebox gave you the correct answer.

Guest47904

What is a PCM kit?

Does the car in question run?

Does the PCM go through it's prestart diagnostic when you turn key on but don't crank it?

BigWil

It is the OBD I reader that I purchased not the ones they used to loan out. It has 3 pins not 2. Reading both the manual for it and the buy over the counter repair book for the car they both explain the 2 pins plus the ground for a total of 3. So all this said the main answer here is still that the low end reader won't work? My smog guy has even put it on his machine and he says it doesn't produce codes either. He said maybe there is a short in the system somewhere. I just wouldn't know where to start looking. Harness all looks good. I've unplugged and reset the system. Same results.

I've checked the cig lighter and it works fine. I checked all fuses while I was at it. Thanks for that.

Maybe one would call it an ECM/PCM Tuner Kit instead of the term I used. http://www.tunercat.com/ As I said though if there is something wrong with the system then my money would be wasted.

Thoughts?

Big Wil

BigWil

Yes it does. And pretty well so far. Need to check my codes and get anything fixed so I can smog it then tune it for performance.

Nope. In key on engine off it just sits there with the solid "service engine soon" light lit. I don't even know that the 94 LT1 OBD I produces codes after start. Heard that it doesn't and can't get to that point to verify in either case.

Big Wil

shoebox

You just have not used the correct scanner on it, yet. Forget trying see a flash of a code 12 or use of a $29 "code reader" you plug into the DLC. Won't work. Can't do it.
I don't think there is anything wrong with the PCM.