I had a 5858 turbo kit with built 2.0 tuned by english racing running at 26psi. I was on the freeway wot on 4th gear about 6k rpm and shifting to 5th gear, all of the sudden there was NO boost on 5th. I did not notice any weird sound whatsoever, boost gauge still shows negative pressure on idle. Engine was idling just fine. Will it be the wastegate got stuck open or the turbo failure? Any other thoughts will be helpful.

 

Check for charge piping blown off

 

 

Everything is in place nothing has fail off

 

Need to do a boost leak test to know for sure.

- Robert

 

If the turbo failed, there would noises and smoke. If the wastegates were stuck open, you would hear exhaust constantly coming out of the dump tubes. Make sure something didn't go through the intercooler

 

I think i did not clarify what I meant by no boost. On the boost gauge, its always negative even im wot, and it struggle to climb on rpm felt like there wasn't a turbo.

 

Yeah, sounds like your classic massive boost leak.

 

Yep, boost leak test should be 1st step. Might look like couplers are all on there but it could have ripped a hole in the coupler, blown out the intake manifold gasket, ETC. Boost leak test is step one.

- Robert

 

Update - external wastegate got stuck open. Problem fixed

 

Has anyone had to oil up the rod to wastegate connection? howd you fix it?