Please read entire post..sorry it is sort of long.
About 8 months ago, I tried to take off my factory cruise control. I lost converter lockup even though I am not sure if I knew it was doing it before that. I put it back in, but the shift points changed. They went from 15,25,35 and engaged lockup at 45...... then it went to 15, 35, 50 and no lockup. I know it isn't locking because you can tap the brake pedal and the RPMs don't change.
About 2 weeks ago after messing with a bunch of wires under the dash while fixing my brake/backup light problem... it started working. Now it did get a lot cooler around then. It wasn't driven for about 2 weeks. It went back to lockup shifts I listed above.
It then went to only locking up when the truck was "cold" It would cycle a couple of times after shifting into 3 and 4 then smooth out. It would stop after braking when warmed up or if I had to engage kick down. It hasn't come back since about a week ago. There is no slipping, it shifts real good. I don't go faster than about 55-60 since 55 is the highest speed limit around here. I don't know if lockup occurs at a higher speed when it does this.
I confirmed that the brake switch is functioning. the vacuum switch is hooked to full manifold. the TV cable is adjusted just fine. Also, this truck has a swapped in 350 from 1970.. the LE9 305 is long gone. The ESC is still there but every wire is cut at firewall. I don't know if this truck was EGR bleed transmission or not. The RPO is MX0 with K34 cruise control. Vacuum diagram code is DFH which I can't find anywhere online...
Does that sound like a bad 4th gear pressure switch? Converter going out? Vacuum switch is failing? any help is appreciated.
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I have this switch
It has an ORANGE wire that is hot all times. It has a WHITE wire that is hot when the brake is pressed. This plug is closest to the plunger. (I thought the brake plug was suppose to be furthest away from plunger?)
I also have a plug that has two GRAY wires into one side of the plug. There is a GRAY/BLACK wire into the other side of the plug. GRAY/BLACK is hot all the time. The two GRAY wires are HOT when the brake pedal is at rest. This plug is furthest away from plunger.
I also have this switch
It has a LIGHT BLUE and a BROWN wire running into the plug. It also has a vacuum hose out the back. This switch is to the right of the brake switch.
On the other side of the column I have this white plug.
It has a LIGHT BLUE wire, 2 WHITE wires, BROWN wire and 2 LIGHT GREEN wires.
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I am wondering if things are plugged in wrong.
this pic (WHICH IS NOT FROM MY TRUCK, JUST FOUND IT ONLINE) shows the LT BLU and BROWN wiring on the same switch with the brakes. That clear plug is on the other switch with the red plunger in my truck.
Wiring diagrams show LT BLU and BROWN to brake switch with reference to stop lamp. It shows 2 GRAY and 1 GRAY/BLK to "brake switch". I assume that this means the release switch with the red plunger and not the black switch since the diagram says REF STOP LAMP for the LT BLUE and BROWN.
Do you think it will make a difference if I switch them around. Could I have switched them around when I tried to take off the cruise or maybe it got messed up when PO made the engine swap?
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