Okay two questions:

1. I have a 1995 Z28. I hear its OBDI, but it's also a crossover year and can be OBDII. How many pins are on each? I forget. And OBDI doesn't tell you if there is a misfire, wheres OBDII does, correct?

2. Okay, not forgetting the former questions, I've posted before about my rough idle and highway problems. I've pinned it down to a combination of my engine mounts and probably my Opti (already read post on diagnosing). So I put it up on jack stands, take it back down, and now when coming to a stop, it doesn't lug or anything. Entirely smooth. WTH?!?! Here's what I did while under the car:

----inspected for a short in the starter motor which may have been causing inconsistent starting
----Pulled off the 8 cylinder plug wire and put it back in (for kicks, no really).
----Checked for arcing on the plug wires (still need to check the coil).
----Messed with a plug wire that was taped.
----Tapped bell housing (for kicks, again).

So what could I have possibly done that would have caused it from lugging to a stop (like stopping while in gear--no clutch engaged) very gently to running perfectly smooth. Any help on BOTH questions would be great! TIA!

 

1. All 95 F-Body LT1's have an OBD-I PCM, and an OBD-II style 16-pin ALDL connector. OBD-I does not include misfire detection. If you want to use a 12-pin OBD-I scanner, Shoebox has a guide:

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

2. A plug wire that has been taped is not a healthy plug wire. Electrical tape does not contain 30,000 Volts. It should be replaced.

 

Thanks so much injuneer! So then, would it be better to buy the OBD-II scanner and would it work straight up? Or should I buy an OBD-I scanner? I know there is a difference in cost with some, but that's not something I am really worried about at this point since I know I will own other vehicles with ODB-II.

 

Look at the picture that Fred posted. You need an OBDI scan tool adapted for use with the 16 pin ALDL.

 

So basically you can't just hook up a ODB-II scanner to it?

 

You can "hook it up".... but it won't work. You can not read an OBD-I PCM with a scanner that is intended for use on an OBD-II PCM.

There are scanners that will read both OBD-I and OBD-II. But if you have one of those, you would have to use it in OBD-I mode, with the correct adapter plug, or using Shoebox's "jumpers".

 

Perfect, that's just the answer I needed. Thanks!