Ok, this isnt my camaro but i figureed what the hey. I recently bought a 1984 chevy scottsdale and the transmission takes a while to shift into second, The throttle and kick down cables where in need of replacement so i thought his may have been the problem. I had my mechanic replace them for sake of time, and he says that it now shifts better but still has a slight hesitation before shifts (I havent picked it up yet). He said that ill have to let off the throttle a little for it to shift. Any advice. I am hopping that it doesn't need to be rebuilt I know from what I have read that th350 are easy rebuild but I don't have the time or experience to mess with it and I am praying its something else.

 

Is the modulator connected to manifold vacuum?

 

I dont know i know the previousbowner said that it had a vacum line with a crack i told my mechanic and he said all he saw was that a line that uset togoto the orginal distributer was disconnected. Where is this modlure located do you know how i can chefk

 

The modulator is on the passenger side rear of the trans case, There's a short piece of vacuum line that slides on then onto a 3/16" steel line. The steel line runs up the side of the trans to the back of the intake manifold with a U bend, The line slides into a fitting screwed into the intake with another short piece of vacuum hose.

Even if both vacuum hoses are hooked up, A faulty modulator will cause pausing shifts. A modulator can be tested with a mityvac style tester, Seems like your "mechanic" would know how to troubleshoot this, If he doesn't have a tester, Modulators are cheap enough to just replace and try before jump'n into a major rebuild......

 

Basic of basics.
I would be looking for a better mechanic especially given his comment "to let off the throttle a little for it to shift" which is obviously letting the engine vac increase

 

If the line was off, the modulator wouldn't work at all and the transmission would only upshift at a very high rpm. The vacuum signal from the intake manifold allows it to upshift based on engine load.

Provide a vacuum source to the line on the intake manifold. If you don't have a hand held pump, simply sucking on the line and plugging it with your tongue will also work. If you can't pull a vacuum or it won't hold, then there's a leak somewhere.

Is the newly replaced detent cable adjusted properly? Push up on the lock and push the cable back. Move the throttle to WOT. The cable will ratchet/click as you pull it tight. Hold the throttle at WOT and push the detent cable lock back down. Sorry I can't explain the detent cable adjustment any better than that.

 

thanks for the advice

 

well 1 new modulator and 1 new line later tranny is shifting fine again, thanks guys for the help

 

If you ever have a misfire or notice the engine smoking, you want to check the line from the modulator to see if your sucking trans fluid into the intake through a ruptured diaphram.