Looking for advice on issues with my 2008 cobalt SS (LNF) with GSM1. Here are the symptoms of my car for the last few years.

- Rough starts
- Car can't start
- Limp mode
- Misfires
- Surging / bucking
- CEL's ever other week

It used to throw P0101 (MAF), and P0106 (MAP) a lot. I checked the MAP sensors to see if they were solder and crimped right (GSM1 new bosch sensors) and found it was fine. I did however zip tie my lower MAP sensors wire to the IC and since then I have not seen a p0106. That never solved my problem though. At least once a month I go into limp mode now, sometimes more often, sometimes less often.

I have been THROUGH 4 MAF SENSORS already!! I keep taking it to the dealership, they see the P0101, test the MAF and it fails the test. It gets replaced, car works OK for a couple weeks and my problems all come back. Car is pretty much stock, so nothing should be messing with it. It currently has..

- GSM1 tune
- Pedder springs
- Rear sway bar
- AEM drop in filter

No one seems to have an answer. This is just one of many problems I have had with the car. I swear I bought a used lemon. The GM techs just go 'huh' and say they replaced the MAF sensor and don't give a **** to find out why I am on the 4th MAF sensor in ~45K miles. So at this point I think I will have to solve my own problems since GM can't seem to fix their own car.

Either way I am currently looking for some advice from the smart guys on this forum. My thought at this point is to get HPTuners and start logging data to see if I can find the problem. Does that sound like a good idea? Is anyone else having problems like this? At this point I am desperate for help...

Example problem from 2 days ago..
I was driving down freeway at 70ish. Car starts to 'studder' (like power coming and going, car jerks slow like I let go of gas or hit break). Since this happens so much I know whats coming, and try to hit the gas and see I can't make boost (limp mode). CEL starts blinking and I have to throw it in 4th to keep at 70mph because such a lack in power. I pull off at the next exit which was close, put car in neutral while coasting, shut the car off and start it back up. GUESS WHAT?! I have full boost and car is running fine. I have not gone to see what the code is, but I would bet its a P0101 (MAF) issue like it always is...

 

First, if you can get the plug and play harnesses for the MAPs do so. Will save you tons of heartache.

Next, if you have the stock airbox get rid of the AEM and put it back on. Run it for a little while. See if that changes anything for you.

 

So the issue still continues. In the last month I have thrown two P0106 (MAP) and one P0101 (MAF) CEL's. I cleared out a few CEL's by unhooking the battery to try and get my car working so I can drive around before I was able to make it somewhere to check the code.

Here is what I have done in the last month:
1. Clean both MAP sensors and MAF sensor with MAF sensor cleaner
2. Put in NAPA paper filter ($32 WTF?!), instead of my AEM filter

I have not had a CEL yet with the paper filter (as I just put it on 6/26), but I already went into limp mode today. I just put in neutral and restarted car and it was ok.

Below is a link to my lower map sensor, which has oil on it (and seems to be motor oil). That may be my P0106, but that does not solve my arch nemesis P0101. Here is the link to see the difference before cleaned and after. Any ideas on the oil on the MAP sensors?
lower map sensor - Imgur

I have read so much about these issues, but I have not ever found anyone with a definite answer on how to solve this issue. The car runs great sometimes, ok others, and barely running all within minutes of each other. What is the best way to figure out what is causing these issues? HP Tuners logging? I have a feeling the sensors are throwing crazy numbers skewing the formulas to put the right fuel / air mix in.

Any help from tuners, techies, people with this problem, anythign is VERY MUCH APPRECIATED. Thanks for all your help!

 

PCV oil separator might help keep those sensors clean. I'm ordering mine from Powell real soon.

 

If you have oiling on your sensors you'll get the p0101 for sure.

But that's not your issue, I don't think. In fact, I'm sure of it. You have a GMS1 tune, which means GMS1 sensors. But the picture shows a sensor with blue, not black o-ring. Wrong o-ring. It's probably leaking.

 

O-RING 3 Bar Map Sensor 12626998

You need 2. Since they are 3 bucks and change each and you'll probably rip at least one putting it on get 4.

 

I will look into this. Can anyone with HP Tuners and diagnostic experience let me know if the following can be obtained?

- Lower MAP sensor output
- Upper MAP sensor output
- MAF sensor output
- Can the pro version of HP tuners data log our cars w/o the laptop?

 

Awesome info! So those MAP sensors could cause the P0101 (MAF) CEL without any P0106 (MAP) CEL?

I never even thought to check that, if that is my problem I am going to have to give you a hug

 

If you have the blue Bosch sensors you have the wrong o-rings in, and they are leaking pressure. That will 100% of the time give you a p0101. The ECM is getting measurements from the MAPs that make no sense compared to what it is being told by the MAF (which is after the MAF). Why? Because air is leaking by after the turbo. Replace them with the black o-rings that I linked.

 

Toommy sounds like you are having the same issues as I.
As sox fan mentioned the Bosch sensors come with s small diameter blue oring.
My kit however did come with larger. Diameter blue orings .
When you order replacement rings they are black.
When putting the sensors in and out you can tell if they are fitting tight or if you have the small oring it will be loose.
Have you found a fix I am guessing boost leak upper pipe that's what I have been told is my problem.
Mine is still not fixed.hope yours is.

 

Actually i think the stock bosch three bar map sensors come with a small outer diameter green oring
as i mentioned my kit from a year back came with blue larger outside diameter orings
replaced recentley with the black orings same outside diameter but the black orings are much stronger less app to leak in my opinion.
Sounds like Sox fan has put you on the right track

has this fixed your issue I am really curious since it seems that there are a bunch of people still with this random limp mode issue.
Is the powell system the only one working for keeping oil off the sensors?

 

OK, so I ordered and installed the new o-rings and they definitely help my car running better. Right after I installed the o-rings I went for a test drive and got another CEL, which was a p0010 and a p0011. I bought the new intake sensor, but I have now noticed that I have oil leaking from it or my HPFP, so trying to get some time to get those two things fixed and install the new sensor!

Either way it was one of my problems, and was making another problem not show up as I had never seen any p0010 or p0011 codes before. I still need a catch can and to figure out why so much oil is getting on those damn sensors, but that will be a little later down the road for now....

Thanks so much for seeing those o-rings man, I really owe you. Now I can keep digging down the rabbit hole to make this thing happy

 

p0011 and p0010 are intake and exhaust cam actuator solenoids. They seem to last 75 or 80 k miles. they cost like 75 bucks to replace the two and take 10 seconds each to do. The are right on top of the engine, next to the number 1 spark plug.

 

Im having the same problem 08 HHR 2.0 Im getting a po420 code first the fuel trim is at 1 then after 30-40 miles more codes po451 evap p2178 trim rich po101 mass air po300 miss fire po106 map then goes into limp mode clear codes ok for day then starts over. seems like random codes just pop in then limp mode. I have a hard time believing the sensors are going bad. It has the LNF upgrade kit with the crimp connectors. There must be a fix for this. I did do a boost pressure test to 20 psi ok very slight leak at hoses where plastic crimps are. also smoke checked it ok. anyway to check the pcv both? anymore testing I can do? convertor is still under warranty but I need to find the problem of going into limp. Thanks for any help!

 

I can confirm this fixed my codes and it's incredibly easy to do. Part numbers are 12655420 and 12655421.

I have been having the same issues as the OP and I'm so happy to have a possible solution. I'm going to be so disappointed when I find the correct o-rings on my sensors.

OMGOMGOMGOMG Blue o-rings on my sensors!

 

Have you pulled the upper and lower tmap sensors?
Any oil present.
If so clean with maf cleaner
Same with maf.
Pull battery neg cable wait 15 minutes
Try that

 

I now have the new o-rings for the sensors. The top sensor went in fine. The bottom sensor on the piping I'm having trouble getting back in with the new o-ring. It won't fully fit into the hole. Any tricks to getting it stay in there?

 

is it going into a stock pipe?
are you positive the sensor you are putting in has been trimmed to fit the pipe since the top of the pipe has the raised part and the sensor has to be trimmed.

if so make sure oring is fully seated in the groove on sensor which I am sure you know

then a little oil on the oring and in the pipe where the sensor goes it should pop right in.

 

I'll double check the trimming on the sensor. I can see that the o-ring is just not fitting in the hole. I have o-ring lube from my paintball gun that I thought of trying but wanted to come here first. I'll go with the oil route. I just didn't think that was an option since getting oil on sensors is bad.

 

Thanks!Yes there was oil on the lower one cleaned it had the blue oring replaced it with the black one. Upper has the black oring cleaned the mass air also installed new ac plugs. po420 code comes in with in 10 miles. Back to the dealer they said still under warranty.Not that this will fix it!Has anyone had a custom tune maybe this could fix it??????????

 

Here is a thread that may help on the P0420 code
https://www.google.com/url?sa=t&rct=...51773540,d.eWU

where you will find the following info

 

Question for you guys w/ oil on your sensors and going into LIMP mode. Do you have issues when the humid goes way up? I live in Ohio, and the humidity here can be a nightmare. Yesterday I was in LIMP mode all day, and I would say the humidity was close to 95% (it was MUGGY). I am just curious if others are seeing the same pattern...

 

Hopefully my issue is gone for good with getting the oil on the sensor .after the pcv valve was replaced I am seeing no oil on the sensor
I do remember reading about solstices possibly having an issue where the intercooler was creating enough condensation where gm ended up putting a trap on the bottom of the intercoolers on the lnf cars

"Replaced Charged Air Cooler" PIP4197 - Pontiac Solstice Forum

 

Well that is fantastic news!!! What was wrong with the PCV valve (that is the little thing that comes into the air intake BEFORE the turbo right?)?

And as always, thanks for all the help, seems like this thread may help a lot of people out!

 

Actually the tube before the turbo intake is designed for fresh air to enter the engine as part of the pcv system.
The pcv valve that I had replaced per the gm engineer is located in the intake manifold.
Seems it was not closing all the way under boost and letting oil back into the intake under boost.
Thanks to everyone here and other sites and some others that I need to get an OK from before listing there usernames and of course my dealership and mechanic
It is running great hopefully for good.