2003 Grand AM Lockup TC

[ms14796]

I have been browsing the tech support forums looking for information on the 2003 model year Grand AM with the 2.2l Ecotec 4spd auto and couldn't find any thing. So hear goes.

With 118,000 miles on the tranny I took it into a transmission service center in Abilene to have the tranny flushed and new filter installed. I told the tech that I noticed when hwy driving it tended to shift down a lot (about 500 RPM) on small hills. He test drove the vehicle with an analyzer hooked up and discovered the PCM was not locking up the torque converter. He could do it manually from the analyzer so we know the solenoid is working. So before I take it into Chevy dealer to have the PCM reprogrammed...
Does anyone know if there is a Tech tip issued on this problem in the past and what the fix was? I have to get this problem taken care of before I can get the tranny serviced.

Thanks.

[troy1]

Just because he can "force" the computer to lock the TCC doesn't mean that the PCM is bad or needs to be re-flashed. I could be another parameter out of wack..

[xeroinfinity]

I would advise against the trany flush.
You think you have problems now, wiat untill its flushed.

The trany shop should know whats wrong from thier scan.

It could just be a wire or connector loose/damaged.

Plus your 2003 should hav all the updated trans parts.
Dont think thiers been many updates since then.

Good Luck

[ms14796]

Sorry for replying so l8t. Ive been out of town and finally able to get back on line.

I should have explained better; I took the car into the GM dealer and had them evaluate the tranny. Problem was in the PCM software so they reflashed PCm and after that, no more problems. I took car into transmission shop for a flush and filter change. That was last September 2007. Around April the fuel pump went out and I changed it out. Of course I had to disconnect the battery. Since then I have noticed the torque converter lockout has reverted to it's old ways. Intermittant lock release. So I was wondering what the relationship was between the TCM and the PCM. Is there a program loaded into the TCM or is it a dummy terminal for the PCM? Is there anyway to reflash the PCM with a Laptop or am I doomed to continue taking this thing into the vendor?

[xeroinfinity]

If it was properly updated the PCM should not roll back to the old data from just disconnecting your battery or anything else.
ITs a flash update just as a mother board would use. And no you cant do much with a lap top unless you hav the Tech II softwares, which is pricey !
The TCC solenoid is just that , it has no brains(cpu). lol