So Walien and I we working on an FD (doesn't make any boost, vac lines were redone by Walien, solenoids were checked for proper operation, check valves as well) so we decided to pressure test it.

The system is sequential, and all stock except for the Apex intakes.

We pulled off the intakes and plugged the other intake pipe and set the air compressor to 10 pounds. The first time we tested in the CRV was breaking loose at 5psi, so we figured it was either a bad CRV or the point where we were putting the pressure.

We moved the pressure input to the top intercooler pipe and tested it again. Around 5psi it would blow out the dipstick and bleed off the pressure.... and other times it would actually hold the whole 10 psi.

We unplugged the line that goes from the oil filler neck to the upper intake manifold (where the large check valve is) and we had air coming out of the oil filler neck nipple. We figured that the pressure was allowed into the intake manifold, but the check valve prevented it from going back from the manifold into the oil filler neck.

Anyway - after we were able to hold 10 psi we took it for a drive and got like 1/2lb of boost. The turbos might be bad... and we have another set to swap. But even if the turbos were *** we should get at least 2-3 psi constantly or we'd have a super high EGT temp wouldn't we? Lots of smoking as well I'd assume?

Just trying to figure the best way to pressure test the system... also note, the car was in the "on" position the whole time, but not started.

Suggestions are appreciated.

 

Even toasted turbos can make boost in most cases, and you'd either have heavy smoke or lots of oil in the intake (or both).

Dave

 

perhaps something is routed wrong? just trying to determine if that oil dipstick bleed off is normal or if something is *** backwards.. need to properly test the charge system =/

 

When pressure testing, dipstick bleed off is normal. All it means is that you don't have a 100% air-tight seal around your rotors, which realistically isn't possible anyways.

Stick your finger into the primary turbo and see if the shaft spins. If you cant spin it with your finger then you might have a seized set of turbos. More likely though I'm guessing your wastegate is stuck open.

 

Would that be an actuator problem? The stuck wastegate... does the actuator arm have to force it in one position. According to my buddy....he didn't even hear the turbos spooling up. I'll have him check it out (since I'm back in AZ now).

 

It would be an actuator problem if anything, or the wastegate door might be carboned up and stuck in the open position.

Connect your air compressor to the wastegate actuator (if you have a stock setup it's the hose with the pill in it, and you might have to pull the hose off the other side of the actuator nipple and put a cap on it) and slowly up the pressure from 0-10psi. You should see the actuator arm start to move towards the turbo at roughly 7.5-8psi. If you get to 10psi and the arm hasn't moved yet, then your wastegate is stuck. It might be as simple to fix as pulling the rod back towards the actuator with a pair of pliers a few times to relieve exterior rust or interior carbon.

It's worth a shot before you start pulling out your turbos.

 

Wastegate being stuck would still produce boost though wouldn't it...

 

If it's stuck closed, yes. If it's stuck open...well it really depends I suppose. I still recommend you test it.

If you have no boost leaks, but you can't get boost, then there is really only two possible problems. Shot turbos, or wastegate problems.

 

Hello all. A friend of mine suggested shot oil seals in the turbo, thus causing the pressure to escape into the oil system. Probable? Possibly.

I guess it's time to replace the turbos. What do you guys think?

 

Replace them dude

 

How would 10psi overcome oil pressure of 80+ psi?

I have never seen that before, I'm pretty sure its impossible. Chances are you have other problems.

The dipstick problem you speak of sounds to me like excessive blowby on the rotors...

 

As stated earlier, if you can pretty easisly spin the shafts by hand, the turbos arent the issue.

 

hook some compressed air up to the wastegate actuator like rossc said and make sure it's opening with pressure and closed without pressure.

then check to make sure the turbos spin freely (as several people have posted above)

just because your car isnt boosting correctly doesnt mean your turbos are bad... come on guys
and i don't think the air coming out of the dipstick tube is related at all to your boost problem.

 

Air leaking past the turbo seals is not probable, or else you would have an intake full of oil and alot of smoke. Don't even worry about pressure in the oil pan when you are pressure testing. It's going to happen, especially if you are pressure testing a cold engine.

If you come on the forum asking for help then you should listen to what people have to say. So far it seems like you haven't tried any of the suggestions people have offered.

 

I have already checked all of the actuators with a MityVac. I guess the OP just forgot to mention that I did. All of the actuators actuate when pressure is applied.

Also, I checked the turbos for shaft play and radial movement; all are within spec.

I'm starting to run out of ideas.

I have a good set of turbos lying around, which I will swap onto the motor.

 

Sorry about that... probably a key bit of information.

 

You need to hook vacuum/pressure gauge up to the various circuits in the turbo control system to determine exactly what is happening at what rpm and under what circumstances. For example, where you talk about the CRV. . .the CRV will most always leak if pressure is not applied to the "A" port while pressurizing the "C" port. It's not too complicated, but you have to understand all the turbo circuitry (vacuum, pressure, rpm, holding tanks, etc) to test it out. I'm guessing your problem is not your turbos, but you never know!
--Jeff