Pre OBD Computer Diagnostics

[iroc343]

Does anyone sell software for a laptop to scan/ the computer of my 87 IROC? I really can't justify $2000+ for a Snap-On scanner and even if I could, that still leaves me without a way to burn a new prom. It now appears, to me, as if I'm going to have to become capable of scanning and programming a chip to get my car to run properly. I would like to know exactly what I need to scan the computer and to modify/burn proms. I did a search and couldn't come up with anything pre OBD. Any help would be greatly appreciated.

[72chevelleOhio]

Originally Posted by iroc343

I'm going to have to become capable of scanning and programming a chip to get my car to run properly. .

Whats got you wanting to spend mega bucks on software to read the limited information available from OBDI? The TPI is basically a piggy-back system on the old gm computer. Pull your ECM and look....IIRC its plugged into the spot where a prom chip plugs in anyway.....
Whats the car doing anyway?

[blindeyed]

Might be what you're looking for:
http://www.tunerpro.net/

Back when I was interested in trying to figure out how to tune my computer, I found that site and it was very helpful and full of information. Until after I realized my computer doesn't have a prom, even though it's OBD1, and that there's no software available to tune it. So I'm screwed lol.

http://www.moates.net/
They have alot of the devices you would need in order to burn proms and such.

[iroc343]

The car is an 87 Iroc five speed. I have installed a GM fast-burn 383 with a comp cams cam, Scoggin-Dickey Tpi baseplate, edelbrock Tpi runners, BBk 58mm TB, accel 24 lb/hr injectors, accel cd ignition, custom motorvation prom, and edelbrock tes headers. The car runs rich when first started, but once the ecm adjusts it runs okay. After another post regarding the rich start condition, I feel that the only way to get this thing to run really right is to dig in and learn how to burn a prom. I did a search and couldn't come up with much, so I thought maybe someone on this site could point me in the right direction. Either that or it's edelbrock and holley carb time.

[72chevelleOhio]

Originally Posted by iroc343

The car runs rich when first started, but once the ecm adjusts it runs okay. .

That sounds like the fuel pressure is cranked too high, or your regulator is simply disconnected. Of course thats on a stock engine, its hard to tell with a modified 383.

[Morley]

The "limited information" from your "piggybacked" OBD I ECM is a wealth of information about the running state of your engine and tune. It will eliminate "shotgunning" parts to fix a problem.
Drop me a PM with your E mail addy and I'll set you up with a schematic for building the cable to go from laptop to your ALDL. I'll also E mail you the program (freeware) for scanning your car and another piece of freeware for editing your .bin files (changing the "tune" on the PROM chip). You can get a programmer for less than $100 or you can get the Pocket Programmer for around $150.

[72chevelleOhio]

Originally Posted by Morley

The "limited information" from your "piggybacked" OBD I ECM is a wealth of information about the running state of your engine and tune. It will eliminate "shotgunning" parts to fix a problem.

Limited as in compared to todays technology....didn't realize I need to specify that. Who suggested replacing a parts?

[Morley]

Originally Posted by 72chevelleOhio

Limited as in compared to todays technology....didn't realize I need to specify that. Who suggested replacing a parts?

"Today's" OBD II systems don't really give you any more info about the state of your tune than the old OBD I systems. They simply have more sensors to monitor and report on. other than multiple O2 sensors they do nothing much for you as far as tune goes. They also monitor and report on the airbag systems and possibly CAN systems (if equipped).

No one in this thread mentioned replacing parts, except me. Being able to scan your engine/ECM gives you a real time look into what is going on and makes it much easier to spot where a problem lies.