I have a 90 R/S with a 3.1L and auto tranny.All stock.Issue is that it shifts into lockup fine.Doesn't shift back out of lockup at lower speeds and car sounds like it's lugging.Like when i upshift too quick on the harley and hit the next gear too fast without enuff rpm.This is when in od mode on shifter.So I tend to ride around town in D mode till i get where will be above 45-55 mph like interstate and then down shift manualy on exit ramp.Or upshift to od manualy on the onramp.
Have found tech to set up switch to make tranny lock up think can apply reverse thinkin to keep from lockup till get to 4th gear but realy lookin to make sure of this and if theres a way ta add a switch to knock it out of lockup and keep it out of L/O till it is in 4th or above 55 mph.Gettin tired of shifting the auto should have just got a standard.But wife can't shift at all.Also need ta make it wife proof.
Lookin for 1st no L/O 2nd no L/O 3rd no L/O 4th L/O/ or potentialy no L/O as situation requires.Same on down shift soon as i drop out of 4th L/O disengeges and stays out till back up to 4th.
Long day + no sleep for past 3 days = hope this question makes sence.
Oh tryin like heck not to buy a shift kit and speedo and all are non cable units all electrical.

 

I had the same problem with a 90RS 305 tbi, I was told by shops the solenoid for the lock up was possibly sticking, I never had tine to mess with it so i dissconnected the lockup plug on the side of the transmission and just ran without lockup, hope this info helps.

 

There's a switch on the brake pedal that opens the circuit when the brakes are pressed. If your intent is to install a switch to disable lock up, you can break this wire and place a second switch in it. If you have cruise control there will be three brake switches so make sure you have the right one.

It probably wouldn't be a bad idea to take it by a tranny shop and have them look at it though. Either way, please don't drive too many highway miles with the tranny unlocked.

 

Naw know better than that.But havin it run like it's in 4th when doin 35 mph is a pain in the ****.Plan to take the tranny to the shop this summer or maybe pick up another unit and have em rebuild/build it.Just right now this is my daily to and from work as well as around town so have ta try sumthin till weather and $$$$$permit.But yea thinkin of disablein L/U till hit speeds where it's needed not at this time too concerned about the mileage differance.Just need to limp thru the winter.So if anyone knows where i can find how the lockup all works please pass it on.

 

Wiring diagram for an 86 but yours will be similar:

http://92b4crs.tripod.com/86wiring/dia-pics/24-0.jpg

Power from the fuse block through the brake switch to the converter clutch ground through the ecm to engage clutch.

 

Nothing.I get a blank page with hosted by tripod in the upper left corner.