Flat_Black13z New Reader
Aug. 18, 2010 5:55 p.m.

So we've got a 99 Crown Victoria P71. Its going in the local demolition derby. But we have a auto trans problem.

When you start it up and stick it into drive (or any forward gear) the transmission acts like its a direct drive, with no torque converter, it just lugs terribly and tries to cruise away like its stuck in gear with a manual transmission. Typically it stalls. Not good for a demo derby. Reverse is fine. Hot or cold doesnt matter. We dont know the previous history on the car, other than they have to run and drive from the police auction. It seemed fine then, but it also had most of its entrails then too. Im not entirely sure if the car had the problem when it was complete, as i didnt have it then.

Any ideas? Is there a lockup solenoid that i can unplug? Also, any ideas for a theme? Thanks.

patgizz SuperDork
Aug. 18, 2010 8:25 p.m.

lockup solenoid sounds stuck. but might need a factory trans wiring diagram as you'd need to attempt to snip the correct wire or risk losing trans operation altogether.

black/white theme, doesnt get any easier

RossD Dork
Aug. 19, 2010 7:22 a.m.

or blues brothers.

Flat_Black13z New Reader
Aug. 19, 2010 6:01 p.m.

TTT keep the ideas coming please. I'll start look looking for a diagram unless someone else has a great idea and chimes in.

I was hoping that it was as easy as unplugging the lockup solenoid on a 3t40.

patgizz SuperDork
Aug. 19, 2010 11:01 p.m.

nah the plug on the 4r70w is like the plug on a 4l60e. unplug it and trans doesnt work cause stupid solenoids control everything instead of the tried and true valves of old

curtis73 HalfDork
Aug. 20, 2010 10:37 p.m.

Find someone with a Genisys scanner, or hook up a volt meter to the TCC solenoid wire. That way you can monitor if the computer is locking the solenoid, or if the solenoid is stuck.

if its the computer, snip the wire to the TCC solenoid. If its the solenoid, yank it out and stuff the hole with a bolt and some JBweld.

Since you mention that it only happens in forward, you can almost definitely rule out the TC itself

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