Mystery Diagnosis 2

[2772]

_________________________________________OK folks, just got my C10 from the trans shop. Filled the tank with gas, made sure the oil level was good and I was off to the races. After a few minutes I noticed something, setting the truck in reverse or drive and it just about shuts down. Have to hurry and give it some gas to keep it going. Park and Neutral are fine idles well. Shifts well too. I was told the put some real goodies in my rebuilt TH350. HD torque converter, shift kit, new flywheel etc.......so WHAT'S MY ISSUE? Posted via Mobile Device
Posted via Mobile Device

[SeeTen]

I'm not positive, but the dying-at-idle (but everything else runs fine) sounds like a vacuum leak. And if I'm not mistaken, I know older passenger vehicles (like mustangs for example) have a vacuum modulator ON or IN the transmission. What it does, I'm not sure. (And where it IS, I can't be sure too. I'm afraid of the work autos may require, so I stay away as much as I can).

Try to google vacuum modulator to get a better idea.

Hope it helps!

[2772]

Thanks Mate.
Posted via Mobile Device

[nightmare]

if i remember correctly, there's supposed to be a vacuum line that runs down to the trans, and plugs in somewhere. like SeeTen said, look up vacuum line to th350

[2772]

Is it something I can do myself or do I have to go back to the trans shop?
Posted via Mobile Device

[hatred]

The trans modulator is on the passenger side of the trans not far from the dipstick. Usually a hard metal line that runs from the intake down to it with vacuum lines used as connectors on each end.

Hope tho helps.
Posted via Mobile Device