need help with boost problem....
 

well....i finally made it through the break in on my reman...but now im having another situation. my boost pattern is all funked up...i get full boost in first gear real quick and i dont feel any transition, but when i shift up, the boost only comes up to about 4psi....but i can acheive full boost if i start the pull in gear..i just cant shift...this causes the next gear to be low boost.....any help would be great.....

Sounds like you may have a bad check valve to the vacuum tank. Tee into your vacuum tank and make a run as described above. You should maintain vacuum when boosting.

ill try that...thanx...

I'm having that same issue, going non-seq on wednesday, hopefully no more boost problems for me!!!

turns out i am losing vacuum to the tank during boost....not all of it, but a considerable amount.....i checked the check valve on the front of the uim, but it seems to be fine....any others i should look for???

i dread the evil "rat nest removal" is growing near again....

cut hose...

vacuum is not escaping the tank unless im under boost....i can shut the car off and the vacuum stays forever....but if i get into boost i lose the tank vacuum....this causes the turbo control system to fail....im begining to suspect a bad solenoid.....

I had a hose split on the TCA side of the Turbo Control Solenoid (the pressure one). When the solenoid opened, all my pressure went to the atmosphere instead of to the TCA.

So your pressure/vacuum tanks can hold pressure or vacuum, and you still have a split/popped off hose.

hmm....ill try that one......putting her on the lift tonight to get a good look.....thanx....

well...i disconected the tca and wired the door shut...that solved the loss of boost when shifting....so im guessing theres a leak in its system.....couldnt find any damaged hoses...so i guess the uim is comin' off this weekend....!!...may go non-seq...

I wouldn't go non-seq. You are almost there...

Do the following with the key off:

1. Climb under the car and verify the TCA is working when pressure is applied to one side, then when vacuum is applied to the other (use a MityVac).

2. Do the same test, but at the top of the hard metal tubes under the pressure tank (see your diagram). This will test the hoses & metal tubes. If it's these hoses, it's an easy fix.

3. Verify both the Pressure Tank and Vacuum Tanks hold pressure/vacuum. They should as the solenoids are closed.

4. If 1-3 are ok, your solenoid(s) are bad or the hoses popped off/split on the TCA side of one of the solenoids (between the solenoid and the hard tubes). Depending upon where they popped off, you may not need to remove the UIM. I think it's probably this, based on what you said above.

There isn't much to the TCA, It just sees nothing before 4500 rpm or vacuum & pressure after. You can even T in at the top of the hard tubes if you want a quick check for vacuum & pressure.

It needs to really slam open at transition, so you need both pressure & vacuum to get it to work right.