4l80e issues

[540' chevelle]

This is what I have: 540 Fast efi big block with a 4l80e. Not a lot of miles and really have not tuned the trans yet with the Fast trans controller just the basic parameters installed. Here is what the problem is.

In drive at 800 rpm and not moving the trans is trying to pull forward. You can feel the cam through the brake trying to pull and you got to get on the brake.. This has a 2500 stall converter how can this be? Can it be the over drive clutch engaged? Can this be a tuning issue?

I think the torque converter is toast.



What do you guys think? Can this be tuned? Also if you take off in drive the car is a pig. But if you put it in 1 first the car is better but not as good as the T400 with a 3500 stall.

Help.

[540' chevelle]

Any ideas at all???Anyone?

[ProdigyCustoms]

Converter is junk.

[LS1NOVA]

Yep converter is junk, stator I think.

[Steve Chryssos]

Any update here? You can go into the force motor tables and see if excessive pressure has been specified at 0% TPS. If the lock up clutch were engaged, the engine would stall abruptly.

As for the converter being junk, it's a possibility. It;s also possible that an excessively tight converter was mis-labeled as 2500. And 2500 is too tight for an engine with the torque curve of a freight train. But some TCU diagnostics are in order before tearing into the drivetrain.

[HWYSTR]

540' chevelle - What year is your car? And what did you do for a crossmember?

[Nemesis RR]

Any update here? You can go into the force motor tables and see if excessive pressure has been specified at 0% TPS. If the lock up clutch were engaged, the engine would stall abruptly.

As for the converter being junk, it's a possibility. It;s also possible that an excessively tight converter was mis-labeled as 2500. And 2500 is too tight for an engine with the torque curve of a freight train. But some TCU diagnostics are in order before tearing into the drivetrain.

I say it is the torque the car is putting out as well. I have a 2800/3000 convertor on a worked ls2 and I get a little creep.