Looking for expert Help

[tracykeyes]

Ok, I just purchased EFI live becuase I am having an issue with LS1 from a 97 vette. It is currently in a kit car so I am not using a BCM. The problem is it sarts then dies after2-3 seconds. Sounded like VATS to me. So I used EFI to check the VATS. It is disabled in the PCM. Now here comes the Expert part!
It appears that when I have an OBDII tool EFILive or other connected to the engine it starts and runs fine. When I remove an OBDII tool the engine goes back to start then die. I tried this numerous times times to validate and it is a fact. When OBDII is connected to a tool the engine runs fine. Very wierd! So I guess my question to you guys is this? Is this older PCM looking for another serial data connection before it will allow the motor to start? If this is correct then is there a way to disable this function or trick it into thinking it is there!
Ok, let the comments and questions fly!! Thanks all.

[Tordne]

So to disable VATS you changed G1201 to "None"?

Very interesting if what you are seeing is correct, that there is a difference to the running when a tool is connected. Also, to verify by connected do you simple mean that the EFILive OBDII cable is plugged onto the OBDII connection, or that you have actually established a connection to the car from the scan tool (through the FlashScan interface)?

Cheers,

[tracykeyes]

Yes the G1201 is set to none. It was this way when I first read the PCM. So my kit factory did disable it. I was using my PC and the ScanTool/EFILive OBDII plug in the OBDII port. It was connected because I was able to disable DTC for a non-existant auto tranny. Also used the scan tool and cleared DTCs and to see which ones to disable. This same thing worked with my other NON-EFIlive hand scanner.

I had another kit builder with the same year say he had to hook up a BCM to get his engine to run. He assumed it was VATS but I think it might be something else.

Wierd! I know but that is what I am seeing.

edit 1-- I think I under stand you question. I need to verify if it the act of pluging in a OBDII plug or actually esablishing a connection is what causes the engine to run..


edit 2-- Ok just tested again. It is actually the establishing a connection to the PCM the allows it to start. Just plugging in the OBDII connector does nothing.

[Tordne]

Is it just plugged on to the OBDII port, or actually connected. Subtle I know but could be significant. The EFILive scan tool connects when you press the tool bar button for instance. Until then not much is going on (at least I don't think so).

[tracykeyes]

Correct. I have to establish the connection before the engine will run correctly.

[Tordne]

Very interesting.. Any DTC's set at all?

[tracykeyes]

Not after I disabled all the auto tranny codes. The EBCM has some but I don't think that would matter.

[Doc]

So is this "Kit" car a manual(or some non electronic tranny)? Instead of disabling the auto codes why not just load a 97 Manual Trans OS(to bypass any possible interference)? Maybe it's not getting a tranny signal? Just a guess.

[tracykeyes]

That is a good thought. I had posted about re-flashing my PCM but I did not get a reply wether it was possible to flash a manual into a Auto PCM. If it is I will give it a shot.
Can I just reflash the PCM using the file on Holden Crazy and select "Program PCM operating system and calibrations"?

The kit uses a porsche G50 manual tranny and no electronics.

[Tordne]

You can absolutely flah an M6 tune over an A4. The PCM is just a hardware platform. It's kinda like you can install Windows 2000 or XP on a PC system.

So, yes you can take a base tune file from my tune site and full flash (OS and calibration) into the PCM no worries