got a ss s\c sometimes when i'm done driving and stop, like in a parking lot, or my driveway i hear this bang sound like someone is hitting my trunk w\ there hand it's nothing mechanical (at least i think) it scares the crap outta me i think someones doing it and geting ready to jump me lol. there's always nothing in my trunk as well, spare tire and everything is secure, what could this be?

 

Does it sound like a "knock, knock, knock?"

 

ya like someones tapping on my trunk with their fist

 

its somthing to do with the fuel system or the electrical system , its been discussed on here , it sounds like someone trying to break into your car lol

 

ya i know i always here at and look in my mirrors thinkin i'm gonna see someone with a bat or something lol thanks for the info on what it is tho

 

i have a ss/sc and it does it everytime in the morning 2 me

 

Another thread on this....

 

Me too. I thought it had something to do with the Rotters. Like if they were clamping on and off a bit.

 

I think he's talkin about the gas cap check. It makes a kind of knock, knock, knock. I love when it happens with a new person in the car, and they go "WTF was that?!?!" And then I say "There's no one in the tr--, I mean, umm nothing"

Or I'll also sometimes say "STFU back there!!" And then the other person freaks.

 

lol ill have to remember to say that

 

Document ID# 1890375
2007 Chevrolet Cobalt


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Subject: Noise from Rear Of Vehicle - keywords canister cold CVS click evap knock L61 LE5 noise rear solenoid tick vent #PIC4317B - (01/23/2007)



Models: 2006-2007 Saturn ION

2006-2007 Chevrolet Cobalt

2007 Pontiac G5

2005-2007 Pontiac Pursuit

with Engine RPO L61 or LE5




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This PI is being superseded to update technical information. Please discard PIC4317A.


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The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:
A noise may be heard from the rear of vehicle; typically 3-5 knocks during initial cold start. The noise may sound like someone outside of the vehicle is tapping on the back window or on the rear exterior body panels.

Recommendation/Instructions:
This noise is from the vehicle's EVAP canister vent solenoid going through the diagnostic cleaning cycle, which is part of the software calibration set-up. Replacing the EVAP canister may not resolve the issue when the vehicle is re-exposed to a cold start. No parts should be replaced. This should be considered a normal condition for 2007 and previous model years.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

It says typically on start up but I have heard of the evap selenoids clicking after a drive cycle. I don't have first had knowledge cause mine has not done it yet. But his document is of GM's Service info for Techs.

 

mines done it during a driving cycle at a light.......

 

I'm happy to see i'm not the only one, my G5 does it every day, it's very loud and sometimes it scares the hell out of me when I don't expect it!

 

LMAO, I get that too!!!
However I only got it after I jacked up the car to put the CAI on.

 

yup i got it......freaked me out at first.....then i relized its an everday thing.

 

It is kinda spooky though. I always forget to expect it when I start the car.

 

I don't think that it's a big deal. Mine does it once or twice a week after I start it up, but also a couple times it has while I have been driving it. However, it mainly does it after I shut it off after I get home from my 45 minute commute. It's nice to see that its the fuel system, I thought I had a haunted spare.

 

you got a problem with yours then... mine ONLY does it 6 seconds after the car is shut off

 

Mmm... another thread on the ghost knock... yep... perfectly normal... happens all the time.

 

Yea its normal it happens to me about once a week.

 

By the way, the title of the post is a little bit deceiving.