OBD I and II

[biggbabysweetz1]

ok i was at work today and was asked "is it possible to upgrade a vehicle from OBDI to OBDII?" to be totaly honest i was dumbfounded, i have no idea. so i ask is it possible?? i guess this guy wants to hook a laptop up to his OBD port to get realtime diagnostics

[Moppie]

Change the ECU, add a few sensors and bit of wiring and I guess its possible.
But you would need an ECU capable of running that particular engine in its OBD I trim.

It would work on something like a Toyota 4age, or Honda D or B series, as they were made with OBD 0, OBD I and OBD II ECUs with very little change to the actual engines tune or basic systems.
Its actualy very easy to go from OBD II back to OBD I or 0 on these engines, as Im sure it is with others made over a similar time period.

The question you have to ask is why?
I can't see any advantage from doing it.

[biggbabysweetz1]

well i guess his basis is hes a computer geek who has a laptop in his CAVELIER and wants to upgrade it to OBD II so he can get diagnostics on the engine while driving. personaly i dont know why you would want to monitor the engine on a factory cavelier, i think the ECM does a fine job of monitoring it

[biggbabysweetz1]

Hes Weird like that

[Black Lotus]

I don't think you need to go to OBD 2 to get real time info from the engine. Both my cars use OBD 1-- GM P3 and P4 ECMs and I know that with the P4 unit (1989) you can get real time data thru the ALDL port into your laptop via a cable and a special program.
It is usually used to collect troubleshooting data on the fly. I.E. to see if the data coming from coolant temp. sensors, knock sensors, etc. makes any sense.
He should hook up with the groupies on a Cavalier site and see what's available (if anything) in the way of equipment and programs for this car.
If his car is stock and is running OK, him wanting to see that data is a bit....kinky. He must be bored.

[biggbabysweetz1]

well what do you expect from someone whos got noting but ferrari pictures on his walls and pistons and various other engine parts encorporated into his living area (piston ash trays, bearing light pulls, etc)
hes a freak what can i say?

[Schister66]

you can do it...Hondas do it all the time because OBD1 is the only way to tune an EMS. You can get real time diagnostics and tune the car...ie dyno tuning!

If he's really into it, he should get a Honda because parts are everywhere and fairly cheap...i have to convert my OBD2 GSR when i boost this spring. I have to get a P28 ECU and a conversion harness...plug and play...

[biggbabysweetz1]

im not sure if hes into the tuning part or just seeing what his engine is up to, ill talk to him tomorrow and see what hes trying to do. I know hes got his laptop in there right now for GPS navigation, War-Driving, music, dvds, etc. but ill see what he says. thanks for the info guys

[LeSabre97mint]

Originally Posted by biggbabysweetz1

im not sure if hes into the tuning part or just seeing what his engine is up to, ill talk to him tomorrow and see what hes trying to do. I know hes got his laptop in there right now for GPS navigation, War-Driving, music, dvds, etc. but ill see what he says. thanks for the info guys

Do a search on Google for OBD1. I'm at work and don't have a link available to post. There are sites out there with PC driven OBD1 code reading.

Here is a link I added: http://www.aldlcable.com/sc/pages.asp?id=20

Regards

Dan

[biggbabysweetz1]

thanks dan, also he is looking toward realtime diagnostics. as to why he wants to do it on a cavelier



UPDATE: awesome, found the site aldlcable.com . ill let him know hes gonna spend 40 bucks on a cable, hes not to into electrical circuits lol

[Igovert500]

Yeah he should be easily able to find OBDI datalogging stuff online that is PDA/laptop friendly.