Hi Guys,
I've spent an hour looking over your exhaustive archives, and it seems to make sense to post a new thread.

Yesterday morning I flew to Tulsa to buy a 2010 HHR SS 5-speed with 56,xxx miles. It has a rebuilt title for body damage 3 years ago, has been driven 30,000 miles since. But I knew I should examine things closely before finalizing the purchase.

I heard a bit of a scraping sound when we started the engine near the center, but it quieted down mostly as it warmed up. Then the test drive: gently floored the pedal and the car accelerated like a low-compression 2-liter engine... check engine light came on, and I fiddled with the (impressive) DIC to show boost: it would bump to 1 or 2 pounds and go back to zero. No boost. Able to drive 80mph (didn't try faster).

After much distress, I negotiated another $1,000 off the price (total of $7,000 purchase price) in case it was not "just a sensor." And drove home.

I stopped in a Tulsa dealership who diagnosed codes for me - here's the list:
P0100
P0101
P0114
P0113 Set for mass air flow/air intake temp
P0299 set for turbo underboost

The mechanic admitted that he didn't have a LOT of experience with the HHR SS cars, but said that without being able to see if exhaust is stopped up (he didn't think likely) or to check further into it (because of limited time on my part), he really couldn't be POSITIVE that the turbo was bad. But he thinks it's likely. He said it bucked a couple times for him (i drove it too delicately to allow it to buck). I think I heard minor little backfire - pops upon shifting, but not positive.

I got 25mpg at 80mph for the 500 mile trip.

Questions:
Is it easy to get to the turbine blade so I can try to spin it and check for end-play?
Oil was clean on dipstick, but I suppose a check of the oil for aluminum is next step too, eh?

Thanks for all your input in advance!

 

Sorry to hear of the issues.

Fwiw. A little pop or minor backfire is normal with the 5 speed SS when changing gears. Seems to be related to the stock SS muffler design. Mine all but quit doing that after I changed mufflers.

Another fwiw. The DIC is the readout on the instrument panel. The RPD is the little unit on the top center dashboard. RPD=Reconfigurable Performance Display.

 

I would check the MAF connector first.

 

If you follow the pipe coming out the back of your airbox, it connects to the mouth of the turbo. It is attached down there by one hose clamp. loosen the clamp up good, pull the inlet hose off, and you can reach in there and spin it.

Don't be alarmed if you find a pool of nasty, sticky oil in the bottom of that pipe, that's from the PCV system. Check out Dbeluscak's thread here. He's working on a solution to this problem.

Also don't jump right to a bad turbo, there are many possible reasons why you are underboosting. My problem was overboosting, so I'll let others advise on this one for now. And there are many causes of misfire too.

 

ALL of those codes are MAF related.

I don't know about SS, but on natural engines everybody has forgotten to hook the MAF back up after an air filter change.

 

Yeah donbrew, easy to check the Maf connector. Sure sounds like something isn't hooked up.

Fwiw. On the SS you don't unplug the connection for air filter service. Removal of the air filter housing lid is all it takes. Just a bunch of screws hold the lid down.

 

Thanks very much indeed, gentlemen!


RFD vs DIC - check! Thanks - that RFD IS impressive - holy mackerel! Cam phase, etc etc wow


Will definitely check for MAF connection (and worn insulation on wires per archived posts? ...that might be a different issue - will check wires too, nonetheless).


Another member pm'd me recommending a check of the air filter (great idea to start with the basics, eh?)


And thank youuu for the description on how to check that turbo for spinnability and/or end play.


FWIW, there are no clouds of burning smoke out the tailpipe, tailpipe is black-sooty but dry. So at least it seems that the seal isn't wiped out...


Again - thanks to all for your input!!

 

RPD, not RFD.

 

DOH - rPd - got it.

 

Or the MAF could be thrash.