I got a 1988 K1500 350 4wd with automatic trans. I did a 800 mile drive with the proper amount of trans fluid required. Now every time I stop and idle while in gear the truck acts like it is trying to keep pushing forward and the idle gets low because of it, causes me to brake harder. What is the potential problem?? What I'm doing now to counter it is put it in neutral every time I come to a stop.

 

Check the throttle body gasket.

Allan

 

That is the little gasket underneath the carburetor? I don't see how that'd make act like this, but Ill give it a look.

 

It's idling too fast, right? 900 instead of 600 rpm?

Allan

 

Idle seems the same, just seems like the torque converter or something is keeping the gear engaged when I come to a stop. Seems like every seconds or two worth of idle the truck tries to push forward out of the brakes. It seems like the Idle is bogged down lower. I dont have a Tachometer on the truck, wish I did.

 

I installed a Cataltic converter (first time in a couple years its had one). The truck runs a little smoother, but now when I come to a stop the truck stalls out.

 

i am having a similiar problem on my 72 c20 2wd pickup with a CGC 350 and a t350, how did the gasket under the carb workout? im out of options

 

Throttle body and carb are two entirely different systems.

Allan

 

I think its faulty manifold vacuum due to which, vacuum will decrease causing the power to reduce making the brake pedal stiffer.

 

i think i have a similar problem, not sure if they are in fact related. My 350cgc will run great choked up (cold) and once it warms it starts to not run so great but still good, if put in gear dies imediately. weve tried adjusting the timing and have it advanced. my theory is it has to do with vacuum. any suggestions would be great!