P1811 code, need help!!!
Thread Starter
Teching In
Joined: Sep 2009
Posts: 3
Likes: 0
P1811 code, need help!!! My girl has a 2001 buick century 3100 with the 4T65-e trans. She went to drive it and it would rev up and barely move, like it was slipping real bad but it was slightly moving. I check fluid level and it was up, fluid was a little dark and I didn't see any metal glitter on the dipstick. There was a 1811 code in there for trans max shift adapt. I don't know trannys so i've read about a couple different things to try like changing the PCS solenoid and new filter. I also noticed the Trac off light is on. What do you guys think, help point me in a direction. car has 108,000 miles. 
Launching!
Joined: Feb 2010
Posts: 285
Likes: 0
From: south florida
Changing the PCS is a temporary fix at best. There are problems with those solenoids but the proper way to fix it is to rebuild the unit and take up clearance in the 2nd and 3rd clutch packs and replace the PCS solenoid and the aluminum accumulators are usually worn at that millage. Basically the computer detects longer fill time for each clutch pack and raises line pressure to compensate which gives you firm upshifts and disables lock up also, could go into limp mode which sounds like yours is in.
Teching In
Joined: Dec 2012
Posts: 49
Likes: 0
sounds like a internal failure if the epc goes bad it will max out the line psi so it will shift very hard. so i do not think the epc is your problem code 1811 sets if the transmission is getting hot or been slipping usually a 1870 code sets trans will more than likely need rebuilt
TECH Enthusiast
Joined: Jan 2019
Posts: 677
Likes: 490
From: Roxana, IL
P1811 is long shift adapt. Here is a link to that code.
https://carscounsel.com/p1811-code/
And a link to an impala forum to for it and how they fixed it.
https://www.impalaforums.com/threads...fixed.1156954/
https://carscounsel.com/p1811-code/
And a link to an impala forum to for it and how they fixed it.
https://www.impalaforums.com/threads...fixed.1156954/
