Removed cruise, lost converter lockup?

[Boone83K10]

Like the title says...

I removed the cruise control servo. I unplugged the wiring, unplugged the vacuum hose. I plugged off the vacuum line. After that I have lost torque converter lockup. It doesn't lock and I have had it up to 65 mph. Before that it always locked almost as soon as the throttle became steady. This truck came from factory with cruise so it has always been there.

The TV cable is adjusted properly. It shifts at 15, 33 and 48. It is in 4th but it never locks the converter. Any ideas?

 

[bucket]

Is it the type that's bolted to the inner fender and has the speedo cable running to it and from it?

 

[Boone83K10]

no, it is bolted to the bracket that holds the throttle and tv cable. the vacuum line runs down under the dash to a switch at the brake.

 

[Boone83K10]

I guess I can put the cruise back on and see if it comes back.

 

[bucket]

I wonder if disconnecting power from it somehow killed power to the vss on the back of the speedo.

My 84's lock-up doesn't work either and someone has removed the cruise.

 

[Boone83K10]

I put the cruise back on and the converter locks up like normal now. I don't think mine has VSS but anyway it works again which is very interesting.

also, I don't know why it bothered me. I live in the mountains were 55 is the fastest limit. I very rarely even go 45 but still and the cruise is not even hooked up to the carb.

 

[Boone83K10]

sorry for the resurrection of this thread but..I readjusted the TV cable. Now it shifts 10, 25, 35, 45

but now the converter only locks up when it's cold.. once the trans is warm it will not lock the converter?????

I don't get it...

 

[89Suburban]

Wow I missed this. Is this on the 87? Let me our over the electrical schematic for that....

 

[Jims86]

Sounds like you unplugged the positive power plug from the brake switch(the one with the vac lines)plug that back in, and you should get lockup

 

[Boone83K10]

this is on an 83..

I have not messed with the brake switch. It is still plugged in. If I unplug the wiring from the servo, I lose lockup. The cruise wiring is all hooked up again (except for linkage to carb), but lockup only occurs when the trans is dead cold, after it warms up I do not have lockup anymore.

One other thing, the servo has two nipples for vacuum, the larger line that runs to the brake switch is fine, but the smaller nipple is broken off and no vacuum line to it. The cruise is not even hooked up to the carb so it's dead to me anyway since this is a play toy truck.

 

[Boone83K10]

Well I had lockup for most of my 25 mile trip, but I needed to get up a long, uphill mountain road and it kicked down to third for climbing... after that the shift points changed back to 15, 38, 55 and no lockup... sigh

 

[Jims86]

Well I had lockup for most of my 25 mile trip, but I needed to get up a long, uphill mountain road and it kicked down to third for climbing... after that the shift points changed back to 15, 38, 55 and no lockup... sigh

What is your vacuum source for the lockup switch on the firewall?

 

[Boone83K10]

full vacuum from bottom of carb

 

[Boone83K10]

sorry to resurrect this thread but it's my thread and I want to


I did some testing tonight. Since my last post, my shifting has been 10 mph into 2nd. 35 mph into 3rd and about 52 into 4th. No converter lockup. the cruise has been reattached (except for vacuum from manifold since the nipple is broken). Today I hop in the truck after it sat all weekend. This morning it shifts 15, 25, 35 and 45 with immediate converter lockup in 4th gear.

This afternoon it does the same but I needed to go to trash dump, on way to dump it quits the good shifting and goes back to the same shift pattern before.

I couldn't understand why. I then bumped the pedal accidentally in an "eastward" pattern (so i bumped it toward the gas pedal). The converter lockup engaged.

WTF IS THIS I SAY...

my guess is that the brake arm has some play in it from side to side and it doesn't fully engage the brake/cruise switch after I depress the pedal???

thoughts?

 

[83K5guy]

If that's the case try to move the brake switch under the dash by the column closer to the arm that depresses it when the brake pedal is released. Have you noticed the brake lights staying on? After I swapped pedals to manual I had to adjust it till it was right.