I have an 87 L98 GTA and would like to buy the tool to check the on board diagnostics (just to see if everything is OK). It runs fine and the SES light isn't on.

Will someone please explain just exactly what kind of computer controls this car has and what parameters can be adjusted (if any)? Any info is much appreciated.

TIA
Frank Brooks

 

GTA,

You might want to visit the DIY PROM message Board on this site. There are several highly experienced programming specialist that frequent that board. There is a very good "sticky" post on PROM tuning basics.

The ECM in our cars is actually relatively limited in its operation, and most of the major operational parameters are stored on the EPROM. The EPROMs used in this series ECM is very common, and burning new data to them is relatively easy with a small software programm and a PROM reader/writer, such as a Pocket Programmer II. I have one of those, and it is all I'll every need in hardware for programming, and was less than $150.

Another piece of software you might need is to interface your PC or laptop to the serial data stream presented by the ECM. A connection cable and software package can be purchased as a package, or the cable can be breadboarded and built by hand. There are some shareware programs that interpret the serial data and present them in graphical form on your PC. It's your choice as to how much you want to spend to save some building time.

So the whole operation doesn't have to cost a lot of cash, but you'll more than make up for that in time invested. Again, the people on the DIY/PROM Board can save soem of that for you as well.

 

Thank you. I did look at that section, and it seemed helpful. All I want to do is be able to check sensors and stuff, though. I dont plan on modifying much, and I would like to replace anything that is defective. Which scanning tool would be best for that?

Frank

 

PS Have you really posted 7875 times in three years?

Wow.