Author Topic: 20 PSI, can't lower it (Read 2865 times)

slorimer · « **on:** January 15, 2008, 06:52:37 am »

On my 94 1.9TD, I have a K14. I believe the waste gate is seized closed as the boost goes up to ~22 PSI at full pedal around 3k RPM. I have not adjusted fuelling and I believe the previous owner hasn't either as the locking collar is still on the max fuel screw. From the info on this site, it seems that boosting that high isn't giving me any gain over ~15 PSI and I could be reducing the lifetime of the engine/turbo (notably headgasket). I can't see any external adjustments other than the screw with locknut on the waste gate. I have played with this and it doesn't seem to change the boost what so ever. Is there a way I can temporarily reduce the boost until I service the turbo?

Is it difficult to remove the turbo and try to loosen up the waste gate?

Can I remove the wastegate without removing the whole turbo?
I have a bentley but it doesn't get into turbo dissasembly.

TIA

jimfoo · « **Reply #1 on:** January 15, 2008, 07:00:37 am »

Have you made sure there are no boost leaks in the tube going to the actuator?

BruceM31 · « **Reply #2 on:** January 15, 2008, 07:13:33 am »

i too have the same problem with my garret gt15 turbo on my caddy. i'll boost up to 25psi, i have played with the max fuel screw though. I have a manual boost controller for it but as much as i play with it nothing happens. I know for sure that my wastegate does move freely by hand, but i am not sure if the acuator is working or not...........

if someone has some insight on this issue i too would be happy to hear!

jimfoo · « **Reply #3 on:** January 15, 2008, 07:25:01 am »

25 psi sounds like way overspeed for a GT15. Assuming you can't see the actuator working, you could take the exhaust or turbo off and hook the actuator to an air compressor, slowly raising the pressure to see where or if the waste gate opens. If it does where it should, then it's in your lines. Otherwise it's the turbo.

jtanguay · « **Reply #4 on:** January 15, 2008, 07:31:37 am »

with a stuck wastegate you could try spraying in some penetrant into the inlet for the wastegate, then apply some pressure from a compressor like jimfoo said. apply pressure, release, apply, and continue doing so until it free's up. this will help push the oil into places where it is needed. don't over-spray it. i don't know if i would use something like wd40 because of the issue with seals though. i sprayed in some of that rust check stuff and the WG seems to work good for me. i can only imagine the amount of moisture that could possibly build up in there and cause corrosion.

i would think that stuck wastegates would normally occur on vehicles that do not normally see full boost.

BruceM31 · « **Reply #5 on:** January 15, 2008, 08:15:16 am »

thanks for the info guys, maybe later in the week when i have an evening off i'll try some compressed air. Just for the record i try to keep it under 15psi, but it will go 25 if i stand on it long enough.....

slorimer · « **Reply #6 on:** January 15, 2008, 08:24:43 am »

Jimfoo- No I haven't checked that. So that would be the metal tube which goes from the compressor side to the wastegate. I'll check tonight thanks.

jtanguay- So I would hook up the compressor to the metal tube and apply pressure, release...(say to 20 PSI). So I would be spraying penetrant into the waste gate opening which faces the passenger side strut tower correct.

slorimer · « **Reply #7 on:** January 16, 2008, 06:04:57 am »

I checked the metal tube for leaks last night but couldn't see anything obvious. So I was thinking of removing the tube and to hook up a compressor. But was wondering, the ends of the metal tube are banjo fittings. I'm assuming there are copper sealing washers on either side that I should replace, correct?

jimfoo · « **Reply #8 on:** January 16, 2008, 06:40:06 am »

Should be, but probably don't have to be replaced as there is so much air, a tiny leak probably wouldn't hurt anything as it would be so small unless your washers were really hosed.