86 auto transmission question

[neil30076]

I have got all teh vacuum lines connected where they should be now, but my latest addition 86 auto shifts very hard - I suspect the vacuum line to the auto-box is leaking somewhere. Can anyone tell me exactly where the vacuum line runs - i see a black vac line running from the 7 way spider down over the bell housing but i don't see it anywhere after that!
TIA
Neil

[Landseer]

Yes, I can.

It connects to a metal line that is strapped with a couple of huge clamps to the top of the torque tube. Hard to see.

Then it converts to flex hose and enters the modulator valve.

You can test its functionality if you have a vac gauge.

I just tested and fixed my wife's 86 auto that had hard shifting.

With exhaust still in-place, I detached the heat shield near the drivers side of the trans, moved it away from trans.

Disconnected hose from mod valve. Attached vac gauge to hose (I have an Acton gauge/tester from Advance auto).

Had wife start car. Saw vac on gauge. Turned car off.

Then, put gauge onto mod valve. Pumped it up. Didn't hold vac.

Replaced mod valve (requires dropping exhaust).

Still shifted hard. Tonight, loosened bowden cable. ( she had it set so she could hold a gear longer and upshift by feathering her foot / works for her in stoplight racing I guess). Now it works great, maybe a little too soft. Probably should give the adjuster on the mod valve another half turn.

[neil30076]

Great instructions, thanks.
Neil