New/used PCM, how to write over VIN?

[Y2kHawk005]

I have searched and searched and I'm sorry if this is an old topic I need help on. I just picked up a new/used pcm from a pick a part place here in Austin, and now I want to perform a "Write Entire". The system states "unlicensed" vehicle. Who can help me with this specific specific question. When I click the Flash Tab, click the Write Calibration index to see Write VIN/Tuner Lock/VATS. Can I input my Firebird's VIN into the new pcm to match my tuning file, or does this WRITE VIN function override the VIN on my tune file?

The good news is and it took some time but I found a PCM out of a 2000 Chevy Tahoe 5.7. I have MPV1 Pro...

Input will be appreciated.

[5FDP]

The tahoe 5.7 computer is different than the Tahoe 4.8/5.3 computer that would match a camaro/firebird 5.7.

They would both need to be P01 computers if your firebird runs an LS engine.

You can't change the VIN on single vehicle licenses. You also need to license any computer if you want to write any change to it.

Besides the VIN number means nothing, unless you have emissions. The VIN can be whatever and it doesn't matter, you can change the calibration to match a previous computer.

[Y2kHawk005]

Thanks, I have my old pcm out and plan to check it out tomorrow. My car is an LS car and the wiring harnesses looked identical, great shape etc. What I am also thinking about is having this computer flashed with my original stock Tune and VIN. This route would be helpful and should be another route to correcting the problem. I'm chasing a P0200 issue with my car where this should be the last thing. Already replaced injectors, diod light tested to find Inj 8, has power 12.05 volts but no Pulse - so a driver issue. I'm so close.......

[mbray01]

Just n FYI i would suspect bad wiring, long before suspecting injector driver issues

[Y2kHawk005]

Yep, my saga continues! Got the PCM apart today to find corrosion (bad but not too bad) inside the computer and where the one of the wiring harness' connects - not in the wiring as far as I could tell. Cleaned the corrosion as best as I could and tried again tonight. Hooked up HPT Scanner immediately. Still Injector Open Loop Fault. Thinking now that PCM may not be able to communicate with injector #8. It provides it power but nothing else.

Now I am leaning to licensing PCM I picked up yesterday and performing a write entire calibration.

I will continue to report...

[Y2kHawk005]

Talk about a code that's kicking my butt! I replaced the PCM - put my tune on it and still have the Injector Open Loop. At least now I can go at the driver communication? I'm a little in the dark here but working through this...

[DrLoch]

Wiring issue. If you can, swap 6 & 8 injector connector to see if you still have an open circuit on 8. If it moves suspect injector.

[s30.hybrid]

Wiring issue. If you can, swap 6 & 8 injector connector to see if you still have an open circuit on 8. If it moves suspect injector.

Since you already ruled out the PCM drivers, then this is the next step I would do in troubleshooting (actually, it would?ve been the first step but...) while you?re swapping the injectors take a real close look at the connector wiring. It?s already been mentioned but the likely issue here is wiring. If you have a multimeter with an audible continuity tester, you can use that to see if there?s a break in the trigger wire between the PCM bulkhead and the injector clip wiring. You might need 1 long test wire and some alligator clips to get to them.

[Y2kHawk005]

Good idea and will try anything at this point! Here is a short summary: I replaced all injectors as I had severe water damage, bank 2, with 2 holes (Cylinder #2) in a cylinder head. Yep, a speed shop that helped out free spun my car on a dyno and proceeded to not tell me about head gasket damage. Dishonesty, theft and life caused my car to sit for 7 years. So, I purchased a new set of heads from Texas Speed & Performance, installed and then I started getting P0200. With the amount of water and tested the right side injectors with 3 bad, I ordered new injectors. I have tested all injector circuits for pulsation with a DIOD light. Tested voltage & Injector 8 has power 12.05 Volts, but no pulse. Diod light does not come on. It doesn't make sense that everything electronically works, just Open Loop Injector issue will not let me tune my car to get it back on the road... I'm looking into the wiring harness again and praying at this point. Through researching this, others have been driven crazy by this too. Almost forgot - I have also adjusted my tune(s) taking out the MISFIRES as per the HP Tuning School (Big Cam LS builds can throw this code). I guess mine ranks as a big cam with a solid roller 265/272 @.50 106 lsa. Soon I hope to have this worked out...

[Y2kHawk005]

Since you already ruled out the PCM drivers, then this is the next step I would do in troubleshooting (actually, it would?ve been the first step but...) while you?re swapping the injectors take a real close look at the connector wiring. It?s already been mentioned but the likely issue here is wiring. If you have a multimeter with an audible continuity tester, you can use that to see if there?s a break in the trigger wire between the PCM bulkhead and the injector clip wiring. You might need 1 long test wire and some alligator clips to get to them.

Excellent and thanks! Exactly what I was thinking. Wiring has been my weakness all along. No better time than now to have to learn it. Thanks again the for reply's and suggestions. Will continue.....

[Y2kHawk005]

I found the bad wire....Blue/White Injector number 8 and #77 in the wiring harness. Damaged inside at the plug.. Replaced the injector plug, Put it back together, car sounds great, idles fine, appears to be all good with no check engine light. Hooked up the scanner and OL Fault Injector. Immediately Diod light tested all injector connections again and all tested good. The only thing I can think of is wire looming to cover any exposed wire... Any other ideas or suggestions? I am running out of possible solutions. I have even tricked the software removing mis-fires to correct the Injector OL Fault as explained to do for large cam LS based GM vehicles. I have a Solid Roller 265/272 106 lsa in 408 LQ4 . Would uninstalling the software and re-installing help?

[B52bombardier1]

Did you clear all old fault codes after repairing the injector #8 connector? It might be remembering the old code.

Rick

[Y2kHawk005]

Working today, will check again tonight but the battery was disconnected (should have cleared the code) and no check engine light.....

[Y2kHawk005]

OK - Found Injector 6 does not have a pulse (via a noid light today) yet has Continuity and Power. I went a step further and tried 2 different PCM's and it would be too ironic for both PCM's to have the same driver issue. I'm still a novice on the software tuning side, but I'm learning all kinds of new stuff along the way. Anyone have an idea for this one?

[blindsquirrel]

Disconnect PCM. Key-on. Measure voltage at each injector pin at the PCM (this verifies the entire circuit all at once - the +12v from INJ1/INJ2 fuses, the injector connector, injector, and control wire to the PCM). If OK, ground the injector wires one at a time at the PCM connector. Can you make the injectors click?

[s30.hybrid]

Glad to hear you got #8 figured out. On #6, if you?re sure the power and signal wires are good from the PCM to the connector then I would focus on the terminals and pins in the injector connector and the injector body. I suspect one is bent or corroded preventing the circuit to compete on the noid light as well

[Y2kHawk005]

Disconnect PCM. Key-on. Measure voltage at each injector pin at the PCM (this verifies the entire circuit all at once - the +12v from INJ1/INJ2 fuses, the injector connector, injector, and control wire to the PCM). If OK, ground the injector wires one at a time at the PCM connector. Can you make the injectors click?

Awesome and thanks!... Have my Laptop and just did the test on both Inj # 8 and Inj # 6 Measured +12v on both control circuits, then at the PCM connector grounded #77 Inj #8 control and the Injector clicked! then grounded #37 Inj #6 control and the Injector clicked, so what I don't understand is why no NOID Light on #6....

Probably the biggest mistake I made when building my car was that I was not that involved with the shop who helped with the tuning, electrical and NOS set up. I unplugged my AEM Pillar fuel gauge and shift/rpm gauge and have no idea where to plug those in.... help there would be appreciated too. I believe I am close....

[Y2kHawk005]

Glad to hear you got #8 figured out. On #6, if you?re sure the power and signal wires are good from the PCM to the connector then I would focus on the terminals and pins in the injector connector and the injector body. I suspect one is bent or corroded preventing the circuit to compete on the noid light as well

Thanks! I have checked, double checked the terminals, changed computers, and everything else. All of this so I can get to the tuning. Currently my Fuel status is reading "Open Not Ready"...... Hope that's a good sign - maybe just maybe...... Plan to drive around in my subdivision in the morning to see how the car responds.

[blindsquirrel]

You 100% certain the noid light still works? Tested it recently on one of the other known-good injector plugs? I mean, not that I've ever been bit by that kind of thing personally, you know...

Have you cleared the codes with the scanner? Disconnecting the battery won't clear codes on anything built in the past 25 years or so.

Does it run and have a misfire? Or are you just going by the stored code and the noid light?

[Y2kHawk005]

You 100% certain the noid light still works? Tested it recently on one of the other known-good injector plugs? I mean, not that I've ever been bit by that kind of thing personally, you know...

Have you cleared the codes with the scanner? Disconnecting the battery won't clear codes on anything built in the past 25 years or so.

Does it run and have a misfire? Or are you just going by the stored code and the noid light?

I am certain the NOID light works as I re-tested all injectors just for my sanity. I am going to check and re-check again today based on the information you gave me.. I have the old school orange scanner I bought from Autozone back about 2006, 2007 and then HP Tuners MPV1 Pro... I even did the HP Tuning School suggestion and went to the Misfires tab and took out the Misfires (Adjusting all not at 32,000 to 32000) Car runs better for sure.... This very well could be a bad plug but then I don't get why it Audible tests and Voltage tests fine. The injectors click, although I will say 6 seemed a bit weak late last night, that's why I will test again today. The code given before was P0200 which I have read has given many people the same crazy trail I have been on for months.. I'm not upset by anything I have replaced. 8 new injectors, new/used re-programmed OEM PCM, replaced #8 injector connector, testing and re-testing - I'm bound to figure this out soon. I appreciate your responses and ideas even if you have never tackled something like this before. Someone who knows electrical or has a different idea is great in my opinion. One positive I will say in a 4th Gen F-body, I'm getting really good at taking off and installing my direct port NOS system. It's a royal pain, with half the engine under the cowl & windshield. Aftermarket A-Bear (coil over) Valve Covers make it challenging as well. All good, will post more findings today...