Rb20det has no vacuum and wont build boost

[pilchera]

Okay my rb20s oil pump went out recently. put new pump,rod and main bearings and put motor back in. all intercooler piping is tight, and all vacuum lines are hooked up..

boost gauge stays at zero. you can hear turbo spool driving but will slowly go to 5lbs of boost when your in it. wont idle. doesnt so vacuum on boost gauge

*** what ive tried...
spray starting fluid on all inj.. all vac lines... all intercooler pipping and intercooler.
no change .

also hooked a smoke machine up to it, and couldnt find any smoke coming out any where..

any ideas?

[pilchera]

all cylinders have between 130 and 140 compression
except for number 3. it shows 2.5psi
did a leak down on that cyl and it will hold 95 psi all day long?


ideas anybody?

[Gabes13]

Probably not right, but is your timing belt set up right?

[l0nestar]

re-verify your test on #3.

[pilchera]

redid it and also did a wet test, and it changes nothing.. timing im almost positive is correct. and if it was timing wouldnt it be more than just one cyl.

still no vacuum, and boost controller is not controlling boost and/or reading, im assuming because there is no vacuum?

[Xit40]

Something is not right with those results. If your not getting compression a leakdown test should not hold 95 psi. Since the wet test didn't improve your compression results you can be fairly sure that your piston rings are ok.

I would boost leak check it first to make sure there are no external problems like vacuum/boost leaks. If that turns out good move back to internal checks compression and leakdown. There is definitely something odd going on with cylinder 3 so i would focus your search there. Maybe even pop the valve covers off and verify that that your valves are working as they should. Double or triple checking the timing, by hand first, is always advised.

Is there a chance you scored the cylinder walls below top dead center when your oil pump went out? That's the only logical explanation I can imagine that you would get no compression yet the leakdown shows no leaks really. The leakdown test should be able to pinpoint the problem. When doing the leakdown on cylinder 3 start it at TDC and slowly move the piston down in the stroke to see what happens. It should hold pressure if everything is good until the valves open. If it doesn't then you most likely have cylinder wall scoring that's causing the problem. Report back