[jza80]

My R33 GTR, basically stock except for exhaust and (now) HKS IC, suddenly is about 0.2 bar low on boost. It used to reach about 0.85 or so, now I am lucky to see 0.6, today only 0.5

There are no leaks with the intake pressurized after the compressors. No exhaust leaks, no smoke from exhaust. One day, full boost. The next, low boost.

I have not done any real diagnosis except for replacing my FMIC and piping with HKS parts, and doing a pressure check. I guess the next thing to check are the wg actuators and piping?

Any ideas with be greatly appreciated!

 

[NicoORT]

Under 20° my GTR take 1.06 bar in peak, if the temperature is highter than 25 i take 0.8-0.9 max in peak... one days my sky have take 1.17 bar!
The exterior temperature have many influence for the bar peak...

 

[andreasgtr]

have you checked the intercooler piping connections yet?

 

[Andy Hornsby]

have you checked the intercooler piping connections yet?

That would be my guess as well.

Andy.

 

[Ged]

Check the small pipework to the blow off valves, its possible they are open almost all of the time so all the boost is venting.
(I have had this problem before)