Trunkflapper

So I read the write-up thread and searched, but I'm still not 100% sure on a few things.

The car is a 97 auto, going to a 99 pcm.

Can I use HPtuners with my 97 vin? Or do I have to run EFIlive?
Do I need to have the new pcm "flashed "? How does that work?

I'm sorry if these have been asked and answered before... I did use the search feature. Any help would be great. Thanks

Quincy

chevy406

Here is the method I used to install a 408 LQ4 into my '69 Nova. I bought a used '99 C5 ECM and wiring harness off LS1Tech. I decided to use a Victor Jr intake with 4150 style throttle body, which of course is cable operated. So I ended up re-flashing the drive-by-wire Corvette ECM to an F-body operating system. Using my HPTuner I first had to license the Corvette ECM. Then I had to license a 2002 F-body tune that I downloaded from the repository. Using the F-body tune, I did a "write entire" on the Corvette ECM. Then I could use the edited '99 Corvette ECM for my drive-by-cable application.

So unfortunately you will have to either license 2 tunes or find someone with an unlimited license to flash it for you. Where do you live?

0C_Williams@RPM

basically...

1- re-pin the harness to for the 99 cpm (or buy a 99-03 harness)
2 - reprogram the 99 PCM
3- use EFI Live to write your 97 VIN (HP Tuners will not allow)

Trunkflapper

When you say "reprogram the 99 pcm " what are you referring to? Have it flashed to my vin? How will that work if it's a 97 vin on a 99 pcm?

0C_Williams@RPM

You need to read/write the 99 PCM as a 99 and use EFI Live to re-vin.

Trunkflapper

So I'm looking online at 99 pcms and basically they are saying if I do not provide them with a vin at the time of purchase, it will come with a "random configuration " Will this work?

Trunkflapper

And then use EFIlive?

tblu92

Why do you feel the need to ditch the 97 ECM ??? tell us about your engine----

Trunkflapper

The reason for this is not because I want the upgrade. My engine is mostly stock, very minimal mods. The problem is that my 97 pcm has failed, and I simply can not locate a 97 or 98 pcm. I would love to find one and go that route, they just amlost don't exist.

tblu92

Well my opinion would be to FIND a 97 ECM--- the headache of re-pinning and more importamtly(re scaling your MAF ) is no little project--AND you would deffanately need a full tune to adjust the 99 ECM-
A 97 uses the smaller diameter MAF where the HZ table only goes up to 11250
A 99 uses the newer larger MAF where the HZ table goes up to 12000
So rescaling of your MAF table would be a MUST---
If your engine is stockish with a few bolt-ons-- you could just plug in the new ECM and go
Try ECM's for less Or PCM's for less--even try Ebay

edcmat-l1

If you already have HPtuners, there are ways around the VIN/OS mismatch. Again, if you already have HPtuners, and you're looking at doing the swap. send me an email. I can sell you a PCM and help you through the tuning and the VIN/OS mismatch so you end up with your correct VIN in the 99 computer.

Email address is in my sig.