jakesz28

What all is needed to make a 97 use the obd1 pcm? Do you just unplug the obd2 and plug in the obd1?

Thanks for the help.
I have tunercats for the obd1 and may try converting a car for a friend

stereomandan

Yes.

In addition, you need to do one of two things.

1) Solder in the resistor (as shown above) into the OBDI PCM
2) Change the knock sensor in the engine block (when the OBDI PCM goes in)

The problem with option 2 is that every time you switch between OBDII and OBDI, you need to change the knock sensor. With option 1, you simply add the resistor once to the OBDI PCM and you are all set. No other changes required.

Dan

Executioner2k5

is the knock sensor on the motor a MUST for the 97 model? i am thinking about buying an OBDI PCM so i can tune it when i want with my Tunercat but still be able to put my OBDII ECU back in for inspections

Black97SS

Taken from the post directly above yours: OR

If you read this thread from the beginning you should be able to find answers to most of your questions. There are even pictures of the modification you need to make to your OBDI PCM to avoid having to change the knock sensor.

If you make this modification you will have to do nothing more than change the PCM to switch back and forth between OBDI and OBD2

Executioner2k5

thanks :P and thanks for making me look like an R-Tard :}

Black97SS

You're welcome, and sorry, I wasn't trying to make you look bad, I know how hard it is to find info on this, been putting together stuff to do my swap for quite a while now. That's actually why I posted pics of my new PCM, to help anyone that might have been struggling like I was.

Executioner2k5

was yers already like that? and how hard is it really to solder that resistor on there?

Black97SS

Yes, mine was like that when I bought it, it was advertised here as an OBDII to OBDI conversion PCM.

It has a sticker on the outside from PCMforLess, so I'm guessing they did the resistor mod.

MadZ28 sells the conversion PCM here http://www.madtuner.com/index.php?pa...mart&Itemid=26

PCMforless has it on this page http://www.pcmforless.com/index.php?...d=44&Itemid=40

Their prices are $250-$275 but I believe that includes tuning.

How hard it would be to put the resistor in a stock OBDI would depend if you can solder. The parts on the board are fairly large, so if a person knows how to solder it would be a piece of cake. I intended to do this myself but a very reasonbly priced PCM with the mod already done came up for sale, so I bought it instead.

Executioner2k5

would it need a tune from PCMForless or MADZ28 to make it work or do they charge the 250 for just that resistor?

Black97SS

The cheapest way would be to solder in the resistor yourself and tune it with LT1_edit or tunercats. That's the whole reason I'm doing it anyway. Wouldn't be much point to the conversion if you were still going to pay someone else to do the tuning. The software for OBDI is way cheaper than the software for OBDII.

If you didn't think you could solder the resistor yourself and didn't know anyone that could do it for you, then you could buy the conversion from madZ28 or PCMforLess, kind of expensive but I believe you would get a tune with that, making it worth more. From that point on you could do your own tuning with the software of your choice.

Executioner2k5

well i already have tuner cat and im sure either me my dad my cousin or my grand father could solder it on, so all i need it the resistor and the obd1 ecu :P

Black97SS

Yep, you got it.

Zeetwentyfate

ok all of you have 97's ? do you still have to convert to the resistor when doing this on a 96?

Black97SS

Yes, you still do the resistor or change the knock sensor in the block. 96 and 97 are both OBDII.

Zeetwentyfate

i knew thery were both OBD2 but i didnt know if the sensors were another gay GM change