Hooking up a computer to a car with ODB-I port

[imported_goku]

I have an LS 400 '94 with an ODB-I port under the hood and I was wondering where I could get some hardware+software solution to hook it up into my laptop so not only I could recieve engine codes and the like, but possibly (not sure if ODB-I/II support this) tune the car via the laptop so that depending on the conditions get better mileage or performance. I know it may seem worthless for a car like this but I think i'd be very valuable knowledge to know how to do this.

I found this information about it all on wikipedia:
http://en.wikipedia.org/wiki/OBD-II

But it doesn't say much how to go about accessing an ODB-I equipped car. I was also wondering if an FJ80 from '91 had an ODB-I port at all and or is there a way to access information from the car's computer and hook it into a laptop or not.

I don't know of any car forums that would have this sort of information so if you're too lazy to give me this info, at least guide me in the right direction, thanks.

 

[Shawn]

You can't.

 

[Savij]

Originally posted by: Shawn
You can't.

Well i've got a Haynes manual for my car and I can pull a decent amount of info off of it using just a shorting wire.

 

[Shawn]

Originally posted by: Savij

Originally posted by: Shawn
You can't.

Well i've got a Haynes manual for my car and I can pull a decent amount of info off of it using just a shorting wire.

Correct. But he wants to hook his computer up to it and change settings. Not possible.

 

[imported_goku]

Originally posted by: Shawn

Originally posted by: Savij

Originally posted by: Shawn
You can't.

Well i've got a Haynes manual for my car and I can pull a decent amount of info off of it using just a shorting wire.

Correct. But he wants to hook his computer up to it and change settings. Not possible.

Is this the advancement that ODB-II had over ODB-I?

 

[jcovercash]

If you have to ask if you can do it then most likely you shouldn't be attempting to tune your car. Its not just as easy as changing a few things, you have to actually know what is going on.

And if you did know what was going on you would know if you could tune it or not via the laptop.

[/EOT]

 

[imported_goku]

Originally posted by: jcovercash
If you have to ask if you can do it then most likely you shouldn't be attempting to tune your car. Its not just as easy as changing a few things, you have to actually know what is going on.

And if you did know what was going on you would know if you could tune it or not via the laptop.

[/EOT]

I see, so if I know I can do it with a friend's '01 subaru but i don't know if I can do it with my '94 lexus, then I should do it to the friend's car and not mine? 😕 I don't like this attitude of if you don't know what you're doing, you shouldn't do it at all. HTF am I suppose to learn how to do it then? 😕

 

[jmolayal]

Ok seriously.. Who the hell suggested to make a trial run on your friend's car? These guys are telling you that what you want to do is impossible. I think the point you should have gotten was to learn more, then try to tune your car. I could be wrong though.

-Jaison

Originally posted by: goku

Originally posted by: jcovercash
If you have to ask if you can do it then most likely you shouldn't be attempting to tune your car. Its not just as easy as changing a few things, you have to actually know what is going on.

And if you did know what was going on you would know if you could tune it or not via the laptop.

[/EOT]

I see, so if I know I can do it with a friend's '01 subaru but i don't know if I can do it with my '94 lexus, then I should do it to the friend's car and not mine? 😕 I don't like this attitude of if you don't know what you're doing, you shouldn't do it at all. HTF am I suppose to learn how to do it then? 😕

 

[Shawn]

Here is a diagram for the OBD-I connector from a 1990 miata. As you can see they aren't standardized like the new OBD-II connectors and there isn't much you can do with them anyway. Basically all you can do (with this car at least) is: put the car in diagnostic mode (to read the codes), turn the fuel pump on, or turn the cooling fans on. That's about it.

 

[Pacfanweb]

There really isn't anything that is referred to as "OBD 1".

Prior to 1996, all manufacturers had their own specific diagnostic tools and computers.

You can call it "OBD 1" if you want, but each maker called it something different. Like, Ford called their different progressions "EEC" for Electronic Engine Control. (EEC I, II, III, IV, and V)
Mazda was "MECS".
GM's back in the 80's was CCC....Computer Command Control. Don't know what they were calling it by the early 90's.

The point is, you had to have a different tool (or at least a different connector if you had a universal scanner) for each one, the codes were different for each one....they weren't similar at all.

With the advent of OBD II, everything was the same....the codes, the data ports, teh language, etc.