Flashed k16s, normally sustained at 0.9 bar.....won't go over 0.4 bar after several drives on different days.

No CEL light, and doesn't throw any codes.

Any ideas what I should look at next?

Thanks

 

If it made boost prior and now only at .4, it's in limp mode or physically incapable of making the target boost (bad turbine, waste gate, boost hose etc- though there should be at least some soft set fault codes**)

What is the background with the car up to this point chronologically? Whos' flash are you using? Have you made any adjustment to the wastegates (a good flash should not need any tweeking to the wastegate actuators)? Did the problem just appear after many miles of driving or did it happen immediately following the flash?

 

check all boost hoses...boost leak?

 

Try a quick disconnect of the battery for 20 - 30 seconds and retry? reset ECU? I had a similar problem and his cleared it up?

 

Could be a bad MAF too.

 

Also could be a dirty MAF. Mine went into limp mode once with no CEL and no codes. Cleaned the MAF and everything went back to normal.

 

I had this and it was a split F-pipe. Can you hear any boost leaks?

 

Thanks for the responses....

Car has been flashed for 2.5 years, always ran great. It has the original MAF, hoses, and diverter valves so I'll check these out.

 

Get a Durametric scan tool, mine did a similar thing .4 boost no cel. Ran the tool turned out it was a bad connection at the knock sensor.
Took half the engine apart getting to it turned out both wires were broken off at the connector. Easy fix, problem solved but if it wasn't for the durametric. I would have been just throwing money at it trying different things to figure it out.
Well worth the money, has come in handy on many occasions.
You wouldn't regret it.