Well I thought I would post this on here even though I have an HHR SS
Since someone on here may have experienced this issue and resolved it.

My HHR SS Shutting off / Running rough for about the first few minutes each morning ?'s
well I did have some other info on another thread concerning a possible air filter issue and Mass air flow sensor issue.

here is the original thread on K&n air filters that I had posted where I thought it may have
been the filters oil on the MAF sensor which has been cleaned

what are my chances of getting a code with a k&n filter - Chevy HHR Network


Now for two days in a row the car will start up fine run through its high idle cycle then I can back out of my driveway and everything seems fine.
But then about a couple seconds after I start to accelerate some where around 10 mph the car starts bucking (like its misfiring) then it will usually shut off. After restarting with a key off key on the car will run better but still skips here and there finally after a few minutes when it hits over about 190 degrees it will seem to run fine but I can still feel a skip every few miles on the highway.
it has now officially turned the check engine light on.
and is also showing a few misfire codes.
I did clean the MAF sensor again last night and it ran just fine afterwards until this morning.
the code that turned the check engine light on is
P101 Mass or Volume Air Flow Circuit Range/Performance Problem
it is also showing pending
P106 Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance Problem
P300Random Multiple cylinder misfire detected
P301 Cylinder 1 misfire detected
P303 Cylinder 3 misfire detected
P304 Cylinder 4 Misfire detected

any ideas since dealer may not even get to it today.
Could it be that the K&n filter that was in the car for a couple weeks with no issues then driving in hot humid wet weather did the MAF sensor in even though it was cleaned?
or maybe a Tmap sensor issue?

 

P0101 is either a boost leak or the MAF is coated with oil. P0106 is a MAP performance code which can be caused when you have a boost leak and the car is basically overboosting to compensate for the lack of pressure due to the leak. The misfire codes are likely due to the above issues. Do a boost leak test. If no leaks found replace your MAP sensors and MAF and you should be good. If leaks found then fix leaks and pull the battery cables to reset the ECM. If misfires persist new OEM plugs are in order (if you have more than 12000 miles tuned or 40000 stock tuned miles you need new ones).

 

really? 12000 miles tuned means new plugs? I think im over that since being tuned by you lol

 

It is a good idea to prevent any misfires which can damage the insulators on the plugs and eventually cause one to crack and fall into the cylinder (This is very rare but if it happens the piston and head would not like this much). These cars run hot once tuned.

 

Thanks for the info
I know stupid ? but I have read several different threads on doing a boost leak check
is there different ways and what would be the easiest way or should I just do search and go with what I find.

So I am assuming there is no oil coating the MAF since I cleaned it twice in the last week
is it possible that I hurt the MAF cleaning it. I used the correct spray etc.

IF after doing the boost leak test and it passes ok which I am assuming it will I would need to replace both the upper and lower Map sensors. Are these the Bosch ones that I received with the GMTU you are referring to? If so where is the best place to buy them if the dealer will not repair under warranty.
I am assuming I could not put in the 2 bar stock sensors while I have the Bosch ones on order.

Also wouldnt it make more sense to replace the MAF first then if problem persists change the MAP sensors.
thanks again

 

Dealer just called
tech drove the car which is still warm said it seemed to run a little off then was ok.
pulled and recorded all the codes I have
I have to pick the car up and then drop it off the night before my next appt. so that they can record
what it is doing when its cold.
Thought they would at least check the maf with the tech 2
would the BOV be causing this.
any recommendations on what I can do if I have time before trying to limp it back over.

 

You have a vented to atmosphere BOV? If so then yes it can cause P0101 as it leaks metered air out every time it blows off. The P0106 could be a bad map or related to the P0101. The misfires can happen as a result of the car running momentarily rich then lean as the ECM tries to correct the A/F.

 

Sorry I am not sure of the proper name of the stock Bov
Diverter valve maybe
That's what I have

 

I am confused do you have the stock BPV or an aftermarket "noise maker" type BOV?

 

sorry I have the stock BPV
drove the car home since the dealer told me to.I think I should have insisted on leaving it since after sitting for 4 hours it runs horribly when it started.
runs very rough then when I check the codes it shows P101 pending.
when its cleared idle cleans right up runs great then sometimes just idling it will go right back to where it was. other times after clearing code it is fine until you are accelerating then it throws the pending p101 code then no boost.

 

Check for boost leaks your IC end tank could be cracked.

 

Well I did not want to post this sooner and Jinx myself.
After having my car run worse and worse starting Friday Night.
I figured enough was enough and the car was not safe to be able to be driven to the dealer.
Checked everything I could think of to keep the story short.
did a quick boost test
checked the BPV
Checked Plugs
Checked a few other things
Pulled and cleaned Tmap Sensors

The tape around the lower tmap sensor looked to be in great shape
did not look like there was any chance of there being an issue underneath.
Pulled the tape off and to my surprise every one of the four wires insulation had
been broken open.
At this point I cannot be sure if there was moisture inside the tape and wires
or if possiblly the wires where contacting each other at times but one thing can be sure
the engine was hitting the wires at times.
Cleaned the wires sealed them up with Plastidip:stirthepot: and taped up with 3m tape.
Pulled front bumper off, moved intercooler 7/16" forward and cut the charge hose about 1/2" to pull the tmap sensor forward more.I am going to look into possibly rotating the sensor 180 degrees if I have any future clearance problems
Did a battery cable pull and normally any time I have ever done a battery pull in the past the car always takes 20-30 seconds before it starts.
This time it started up immediatley and has been running great ever since.
No codes no pending codes
Air fuel ratios look good from what I can tell etc.
::
I would like to take this time to thank everyone on this site for all your help with this and for posting up info in the past as well such as moving the intercooler forward and cutting the pipe for clearance.Without the help of you guys and this site as well as a couple other sites, I might have been stuck with my car in and out of the dealer until I gave up.
But with your help it's alive !:bluesbrothers:
hopefully for quite a while.

 

your better off looking for info here rather than going to the dealer. most dealers dont even have a clue this engine exists.

 

x2 guys like term on this site are great and usually much more knowledgeable glad you got it worked out !

I know what you mean about the lower MAP it sure is close to the AC. wonder about clearance on it all the time (but i'm **** like that! )

 

It is possible the cause of your issue is something like what the OP had.

 

that's why im trolling around getting other ideas I'm gonna get that bumper off again this weekend and take a peak at the electrical connections. I'm thinking vac tank maybe another possible cause as well, I had issues with it last summer (only didn't know that's what it was at the time).

 

I don't think taking the bumper off will gain you any more access to the TMAP and wiring.

 

Well just an update and looking for some help
car ran great all last week after taping up lower tmap harness that was broken
Friday afternoon car started to run poorly again.
P101 and P106.
Keyed off ran ok for a little bit.
Got it home put in new lower TMAP harness adapter from Crate Engine Depot.
car sat about 4hours before I drove it ran great Friday night.
Saturday
and even Sunday on a trip that was one hour up and one hour down.

This morning ran fine and actually started to die on the highway had to pull over car was barely running keyed off and seemed better but still not exactly right.
I noticed the second car started running rough it was still commanding 14.08
but was measuring close to 21 plus
I have it all data logged. I can probably attach a screen shot here or I can email the whole log to someone. I can bring to dealer but at this point it is an on off thing but getting worse just dont want to get stranded.

Any ideas would be great
Tried different MAF seems to be having the same issues.
are we possibly looking at a bad TMAP sensor or bad O2 sensor or is it time for me to give up on this car. I cannot tell you how many hours I have wasted
trying to diagnos this issue.
Dealer just says bring back when it is happening or when you think it will happen.
Time for another dealer maybe?
I am guessing one of you tuning experts can figure this out.

Having trouble uploading Log and or screenshot but I can email them if someone could help me out

 

If it is a HP Tuners log send me the log. starovertexaspaint@yahoo.com

 

I have the file in Microsoft excel document
Which I sent to you and can send to anyone else
I did notice one other odd thing is that the car was running at like 200 and by the time I pulled over and it was running rough it was down to 186 degrees
I have never seen that car cool down that quick.

 

I'm thinking that you have an injector failing.
DI injectors fail in an 'open' position'.
So, if an injector is 'sticking' open, lots of fuel, with the O2 sensor 'seeing' it.
Also STFT seeing fuel too, & maxing out, in your log...
Water temp dropping, as lots of fuel has a 'cooling' effect...

But, you had said that you were having misfire codes for all cylinders,
could there be a sensor, or the ECM, 'telling' all the injectors, to go super rich ??

 

Could be stuck closed. A/F is stuck lean even with +30 STFT which is a huge error. LTFT is -5 according to the screenshot he sent me which is a little rich average but not that horrible.

 

my bad...

Instantly going lean, +30
What sensor would tell the ECM to go instantly lean ??

HPFP going bad ??
Fuel system shutdown ??

 

Hopefully I can learn this info quicker than later.
I appreciate you guys looking into this.
Would a failing temp sensor record possibly bad info.
Another words maybe not really at 186
also recorded AF ratio was high number
So that means lean right

 

Yes the car was commanding 14.0-14.7 but seeing in the 20s A/F wise so very lean even with the STFT being +30 which is as high as it can go.