Just a quick question about this. Were you in competition mode when all this was happening?

 

No. I had actually forgotten about that feature. Reminding me of competition mode now gives me even more motivation to fix the issues I'm currently having.

 

I too had turned off the notifications on this, so I hadn't seen that anyone posted on it...

I have a couple things to add to the thoughts...

1) Mine is not affected (one way or the other) by the mode (in reference to DrLoch's question).

2) I tested the clutch position sensor by turning by activating the cruise. The cruise de-activates the instant you move the clutch pedal at all, leading me to believe the sensor isn't the issue with mine.

3) On mine, it is affected by heat. During late spring through the Summer, it happens all the time. As soon as the cooler weather hit in the fall (below 45°-50°) the problem is almost completely eliminated and only surfaces on days when the temp goes back up over 50°+.

This falls in line with my first experience with the problem being last spring when it started warming up (I bought it last December). The only exception is when you are caught in a traffic jam and/or the car sits and idles for an extended period of time, the first time you run through the gears, it will act up between the first few shifts, but disappears quickly once you start moving again as opposed to continuing for a longer period when it's hot out.

3) I worked with GM and my local dealer who was willing to look into the issue. The Technician went over the car "stem to stern" and involved GM engineers. After 3 different trips to the dealer for different things that the engineers wanted checked, they were unable to determine ANY reason for what's occurring and pretty much "gave up" on it...as have I.

It is really annoying, but there seems to be no known cause or repair for the problem.

I may try swapping the sensors (as RJ RS SS 350 suggested) just for the heck of it. Weirder things have happened!!

 

Has anyone ever come up with a definitive solution for this problem? I don't believe that this problem is normal, designed that way, or built in, because I had a 2008 HHR SS Manual that never once did this. Now I have a 2009 HHR SS Manual that does it intermittently. Mine will sometimes go for weeks without doing it and then it may do it only once or several times in a row. It did it when I test drove the car, but I assumed that it was something simple such as a dirty/sticking throttle body and I'm still not convinced that it isn't. But after reading through this thread, it seems strange that this apparently has been going on for 10 years and no-one has ever posted a definitive solution. I may try the Clutch/Brake Pedal Position Sensor swap and a throttle body cleaning or replacement. ZZ Performance has brand new throttle bodies fro less than $70, but I'd sure like to hear from someone who fixed this problem and what fixed it.

 

All I can say for sure is that I still have not had this issue resurface. It's been over 2 years. And the throttle body was not dirty.

 

Can you feel/see if the pedal is hanging?

Seems to me that cleaning the throttle body with a $5 can of TB cleaner would be a lot easier and cheaper than replacement. A visual inspection should tell if it is dirty enough.

Have you monitored the coolant temp when this is happening? Not the analog gauge.

I don't know how the AlGorethm works re the clutch and accelerator. For all I know the computer does that under certain circumstances. I had a 1996 Toyota P/U that did the same thing.

 

If I'm not mistaken, you are the one who solved the problem by swapping the Clutch/Brake Pedal Position Sensors. I may try that or just replace the Clutch Pedal Position sensor. I don't think those are expensive either.

 

I see no indication that my clutch pedal is sticking.

Yes cleaning the throttle body would be cheaper than replacing it. But if it's not dirty and sticking because it's worn or it's stepper motor is failing, it would need to be replaced. Since they are not expensive, I figure that a brand new one would eliminate 2 or 3 potential causes at once.

The problem that I have with the "it's programmed to do that" story is my '08 HHR SS Manual never did it once. I see several people with 08's complaining about the problem, so it's not just a '09 problem either.

 

I meant the accel pedal.

IIRC; some vacuum hose was my problem before.

I think I recall the SS has a special shift mode, perhaps that has something to do with it? Somebody that knows may chime in.

 

Some reading for generic testing of the clutch pedal position sensor...

P0806 - OBD-II Trouble Code | BestRide.com

Might just lead you to a solution