Now this is weird...

[North Maine]

Ok so I got around to installing my "F" computer today... went along just fine, a 5 minute job. I was expecting to have to do the anti-theft learn thing, so i had the Turbine Doc post printed out and waiting... I turn the key there is no "wait to start", so i crank and she idles along happily, no problems, no stall, no nothing... so I go for a ride, and I feel no difference between the S I was just driving and the "F" i now have... then i'm looking at the dash, and the WTS is on, I let off the throttle and it goes away... back on the pedal and WTS is on again... WTF!?!?!?!?! It WILL NOT WTS when starting, not one bit... but it will come on if the engine is warm and I hit the pedal... is it possible to connect these things backwards? bad connection? I'm lost, cuz the truck drives fine...

so how weird is that s***?

 

[matuva]

Whose reflash have you get?
Is it the GL4?

 

[Turbine Doc]

Odd one for sure, this a junk yard stock F core or a reflash ???

 

[North Maine]

junk yard stock... I didnt think a PCM would go bad like that... so I think I'm just going to end up sending it Heath and have his HP4/GL4 program put on it

 

[Deere Freek]

junk yard stock... I didnt think a PCM would go bad like that... so I think I'm just going to end up sending it Heath and have his HP4/GL4 program put on it

I would do that anyway

 

[gmctd]

Not wierd at all - for testing purposes, there is no WAIT TO START on the first key-on after installing a nuther PCM - yer s'posed to key-off, then restart for proper WTS\GP operation - then go for an easy drive so PCM can relearn driveability parameters, particularly with 4L80E.

 

[North Maine]

But you see, it never did that. the WTS never came on unless the engine was hot and i hit the throttle... you dont think that is weird? I've been running the truck for 2 days like this (today i swapped back to "S") and it has never cylced the GPs unless the engine is above 180 and I'm underway. I reinstalled the "S" and it hit the GPs on the first key turn...

 

[gmctd]

What year is the PCM?

 

[North Maine]

according to the description of the vehicle it was pulled from it's from a 1998 2500 GMC Sierra 6.5L TD 4x4 Auto Trans

 

[gmctd]

How do the connector pins look on the "S" PCM, and the "F" PCM - clean and pristine, no corrosion\oxdation?

 

[North Maine]

The connector pins seem to be in decent shape. The overall condition of the "S" is better, shiny metal still, ect. It has a sticker that says it is a refurbished PCM from Delphi, while the F is not as clean the pins appear to be fine.