OBD1 or OBD2?

Reply Subscribe

Thread Tools

Search this Thread

Sep 30, 2018 | 01:16 PM

N875ED

Thread Starter

Advanced

Joined: Sep 2018

Posts: 67

Likes: 13

From: Lebanon, Ohio

OBD1 or OBD2?

I have a 1995 LT1 and tried to use my Actron CP9580 code reader (OBD2) but it only scans cars back to 1996. (I thought a technically advanced car like a Corvette might have actually switched to OBD2 earlier than other cars.)

So, do I truly have an OBD1 car as I expect, or am I missing something? If OBD1, does anybody have a recommendation on a scan tool?

Thanks!

Sep 30, 2018 | 01:30 PM

rjacobs

Melting Slicks

Joined: Dec 2004

Posts: 2,650

Likes: 632

From: Dallas TX

96 was first year of OBD2, but even it is "weak" OBD2.

Sep 30, 2018 | 02:42 PM

RVAVette

Intermediate

Joined: Jul 2017

Posts: 38

Likes: 1

From: Richmond, VA

Quote:

Originally Posted by N875ED

Bad news is it’s OBD 1, Good news is the best scan tool is really cheap. I recommend a high performance paper clip for like .02 cents.

Sep 30, 2018 | 04:42 PM

pcolt94

Le Mans Master

Joined: Jan 2006

Posts: 5,620

Likes: 206

From: Orlando FL

Quote:

Originally Posted by RVAVette

Bad news is it’s OBD 1, Good news is the best scan tool is really cheap. I recommend a high performance paper clip for like .02 cents.

This is the initial way to go and works well. It will give you any codes in all the modules where if you had a basic OBD1 scanner it would just give you the codes in module 4 for the PCM.
Using the FSM there is a huge amount of information that can be seen other than just codes but you have to have the information and learn how to do it.

Sep 30, 2018 | 08:09 PM

STL94LT1

Race Director

Joined: Jan 2002

Posts: 12,261

Likes: 85

From: O'Fallon Missouri

94/95 cars were OBDI with OBDII ALDL connectors.

Last edited by STL94LT1; Sep 30, 2018 at 08:10 PM.

Oct 1, 2018 | 02:06 PM

N875ED

Thread Starter

Advanced

Joined: Sep 2018

Posts: 67

Likes: 13

From: Lebanon, Ohio

Thanks, gentlemen, for the fast reply. I guess I now I have learn how to count flashes.

Oct 1, 2018 | 07:36 PM

Kevova

Le Mans Master

Joined: Sep 2013

Posts: 6,192

Likes: 750

From: near the thumb in the mitten

OBD2 was dictated by the government.The connector was changed because PCM is reflashed there is no chip. The older style connector is used with Ecms with replaceable PROM ( chip)
OBD1 scanners require the correct cartridge :GM powertrain thru 1995. Snap On MT2500, OTC Monitor 4000, Tech1( The GM scanner) and Tech2 are all good scanners.You will need the 16 pin OBD2 style connector or adapter. There are also scanners that will do both 1 & 2. Paperclip will give you codes, a scanner will give up data. EBay, Craigslist, & Pawn shops are possible sources.

Oct 1, 2018 | 08:23 PM

Matt81

Racer

Joined: Sep 2001

Posts: 352

Likes: 51

From: Austin TX

My dad bought a 95 Firebird Formula a couple of years ago with the LT1 engine. It had a couple of codes i wanted to check out, came across a really excellent bit of software called Scan9495. Link is here. Site includes details on building a cable as well. I think I got the parts for less than $10 thru ebay.

Software shows live data feeds from all the modules, as I recall.

I would assume this works for the same year Corvettes. If course, I also know what happens when you assume...

Hope this helps some!