The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > General Truck Forums > Engine & Drivetrain > LSx Swaps

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 11-11-2018, 07:14 PM   #1
nobox351y
Registered User
 
Join Date: May 2016
Location: LeRoy
Posts: 69
4l80e p0742 Code issue

2001 5.3 with a pre case mounted neutral safety switch 4l80e 93ish swapped into a 87 r20 burb.

Took it out for the first real test drive today and all seems to function well with the exception of the this code p0742.

It seems like the converter is failing to unlock under decel. As you come to a stop the transmission pulls the engine down to about 400 rpm and then it unlocks. It threw the code and after that the converter wouldnt lock up, which is fine until I get it figured out.

Aside from checking to make sure that the tcc circuit to the brake switch has 12 volts when brakes are not applied and 0 volts when they are applied, are there any other options?

I believe I have it wired correctly but will double check that for sure.

Thanks Guys

Last edited by nobox351y; 11-11-2018 at 08:21 PM.
nobox351y is offline   Reply With Quote
Old 11-12-2018, 02:20 PM   #2
nobox351y
Registered User
 
Join Date: May 2016
Location: LeRoy
Posts: 69
Re: 4l80e p0742 Code issue

User error...Still had parts of the 4l60 tune in the pcm. Segment swap to 4l80e settings and all is right in the world.
nobox351y is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 10:22 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com