EXIT1RENEGADE

1994 z28/m6
i cant get a scanner to communicate with the pcm.
was using a matco tools scanner (not sure which model). But every time i try to read the codes, it tell me it has a communication error.

I already checked the fuse. and tried cleaning the prongs in the connector.

Is there anything else that could be causing this problem?!?!

RamAir95TA

iTrader: (2)

It's most likely the scanner itself. Many scanners are not compatible with 94 and prior.

Silly question but the key is ON, right?

You should consider investing in an interface cable and free/cheap scanning software that will tell you 10 times more than a conventional scanner would (assuming you have a laptop as well).

SS RRR

iTrader: (2)

Yes, most likely the scanner you are using is for OBDII only.

EXIT1RENEGADE

yes key was on lol.

i was looking into interface cable and all, just havent gotten around to ordering one...

I do have a Question though that you (ramair95ta) might have an answer for.
i just replaced the opti. ran fine for a few days. After that it would not start. would just crank than when i stopped cranking (with key on still) it would cough thru the intake. messed with the opti harness and it fired right up, and ran fine. The past two days it was doing the same thing. decided to pull the pcm fuse, waited awhile put it back in and fired right up. I drove it around and ran fine till it warmed up, then it started to sputter every time i tried to push it hard. Any Ideas why?

EXIT1RENEGADE

the scanner also told me what connectors and all to use, just figured it would work lol

the scanner was a Matco Tools DETERMINATOR

RamAir95TA

iTrader: (2)

Out of curiosity have you checked the fuel pressure at all, and have you gone through shbox.com's opti diagnosis guide?

EXIT1RENEGADE

i have checked the fuel pressure, with the key on, not running the pressure is at 39lbs, at idle it was about the same, cant think of what it was. i was actually just reading that, im going to be checking that sometime today...

where is the best place to buy an interface cable

shbox

There are many models of the Determinator, but I don't see any that say OBD-I (which is what you need).

EXIT1RENEGADE

ok that would make sense then, thanks for the info

RamAir95TA

iTrader: (2)

I have always ordered cables from www.akmcables.com. MAKE ABSOLUTELY SURE you buy the right cable for your particular year. They offer them in both USB and serial (use serial if you have an older laptop with a serial port - I've found that they are actually easier to use).

EDIT: Looks like the ordering portion closed last year. Buy from www.tunercat.com.

EXIT1RENEGADE

ok thanks for the help

EXIT1RENEGADE

http://www.tunercat.com/cables/aldl.html

is this the right one? it will be used for a 1994 z28/m6 lt1

EXIT1RENEGADE

USB/ALDL-1 ... right? just want to make sure lol

RamAir95TA

iTrader: (2)

Yes, that's the one. You have a 12-pin square connector.