Ok I finally bought a mityvac and tested all the actuators. They all appear fine except the TCA. When I apply pressure it leaks about as fast as I can put it in. I am guessing it should hold pressure and not leak?

Second, in the workshop manual page F-86 it states to NOT apply more than 11.5 PSI to the actuator. So my question is if I am pushing around 13-14PSI of boost does something control how much is applied to this actuator for it to move or does it just use whatever boost you are generating? Should I be concerned with that possibly causing premature failure of the TCA?

Thanks

 

Just wanted to give everyone another chance to answer.

 

The TCA is moved by the vacuum and pressure reservoirs, and since I don't know of any 'blow-off' valves on either system, then they would change peak pressure if you up the boost.

But going to 14psi instead of 11.5psi is not a very big deal. I think they just put that in the manual to cover their asses. In fact, in normal operation, it sees vacuum and pressure, so the net pressure on the diaphragm is probably near 20psi. Since vacuum doesn't change much with upped boost, it will only be a few percent difference in operating loads. No big deal.

TCAs are cheap if bought used. In fact, I have one in excellent working condition, 60k miles, $40 shipped. (Just for fun, get a price quote on one from the dealer)

Dave