Red Daily

I have a 2008 HHR SS 2.0 lnf 5 speed manual with 135k. The only mods i have done are catless downpipe, cold air intake, intercooler pipe with tial blowoff valve, and took out stock blowoff valve and put blocker plate on. I am getting this problem that has completely went over my head and cant seem to find input from anyone i have asked. My car will completely lose all power, usually when shifting into 3rd gear but has done it in other gears. The car revs but will not put power to the ground in any gear and gives off a whistling/suction sound which i have come to find it is the air coming out of my blow off valve. Car eventually stalls when i let off the throttle and will start but will only start and idle if i let the car sit for a couple mins. Really lost on what could be the problem and the only engine code on is the p0366 but i replaced both position sensors and both actuator solenoids not sure why that code is still popping up after clearing. Any info would be greatly appreciated!!!

Oldblue

The code would indicate possibly a damaged wire or pin in a connector

https://www.obd-codes.com/p0366


have you double checked the ground wires sensors connections

Red Daily

I checked the connections and everything seemed to be good. When it stalls my BOV is stuck open and open until i take the vacuum hose off. Is this routed wrong? i believe when i installed it, i hooked the vacuum hose up to the attachment point where existing bov that was hooked up to that was stock already on the turbo

RJ_RS_SS_350

Why don't you try blocking the blow off valve, and reinstalling the stock bypass valve. If it runs, the problem is with the blow off valve.


Has your ECM been tuned for these mods?


If the engine revs, but does not transmit any power to the ground, how are you driving it, and shifting into 3rd gear?

donbrew

Sure does sound backwards. Is there a vacuum hose routing sticker on the bottom of the hood?

1,2,3 &4 are the vac hose clamps.

RJ_RS_SS_350

There is no vaccum diagram. And that is the boost control solenoid in your pic, donbrew.



Here is FMG's pic for bypass
solenoid routing. Post #15
https://www.chevyhhr.net/forums/ss-s...t-61760/page2/

Cat Man HHR

"gives off a whistling/suction sound "

With my experience with Cat turbo engines the first thing I can think of is a loose charge pipe clamp.
It's definitely sounds like a boost loss.
Being you have a 2008 SS you don't have an RPD to see what your boost is doing.
Do you own a scanner that can see this parameter ?
If not, a cheap bluetooth device is a BAFX OBD2 tool you can use to see what the values are.
I don't see how the P0366 code has any bearing on the noise you hear.
How long has the check engine light been on for this code also.
When did it show up ? After a mod was done ?
At 135K were the chains ever been done ?

Red Daily

Got the car at 96k so i have not done the chains, but the sound is coming from the bov not closing. Car has not been tuned, do i need map sensor as well? And i have been driving it the same for the past 40k miles i dont really beat on it either

RJ_RS_SS_350

The blow off valve being open all the time is a huge vaccum/boost leak.

You seem to be ignoring much of the advice given, or you're just not telling us if you are following it.

We've given you the routing for the bypass solenoid, is your routing correct? You need to go back and address all the questions/suggestions.

Your ecm MUST be tuned for a blow off valve, possibly for new charge piping and ic also. If you're not planning on increasing the boost, then the factory TMAP sensors will be fine. I see the upper TMAP, did you install the lower TMAP?

Red Daily

Yes sorry i checked the diagram and it is connected properly i believe. The diagram shows the connection i have is pulling a vacuum into the motor with the red arrows. So it is in the direction of coming from the bov with air flow to the motor. the ic piping i replaced did not have the tmap connection so it is still factory on the factory piping down behind my bumper.