Autozone did not show any caps for 2007 HHR, only one they showed was for HHR model year 2006: CST 5903 (seriously doubt though that there were any design changes to the fill neck for model year 2007+).

Had them bring out both the 5504 and the 5903. They were a little different. Although they were both the same approximate height from end to end, there was a difference in the aparent length of the cylinder part that protrudes down into the filler neck. Plus the 5903 was $27.99 while the 5504 was only $12.99

I had a 5504 earlier this year but I think it was defective, refunded it.

Anyhow, I went ahead and got the 5504 again.

I just thought it was weird that their system recommended the CST 5903, and the price diff + appearance diff.

 

Of course.... more money in their pockets

 

Just kinda curious ... did they recommend the 5903 for the Sonoma too?

 

if it cost more money, then it's prolly recomended

 

I got the CST Locking Gas Cap Part Number 5504 from Auto Zone for my 2006 HHR and it fit great. But...if you don't get it on correctly every time, it will set off your check engine light. Happened to me and the only way to clear it without starting it a zillion times was to disconnect the battery and let it sit for an hour or so that way. If you have to do that, please remember not to shut the hatch completely...otherwise you'll be crawling thru the back of the car on your hands and knees to hook back up the cable. Been there...had to do that.

 

Did anybody catch it on tape? Another way to get it cleared is take it to auto parts store most of time they will check code for engine light for free

 

No...thank god they didn't. Needless to say, I had a few choice words to say as soon as I shut the tailgate and realized what I had done. Figured it would save me a trip to the auto parts store just in case it didn't clear the code. Then I could call the dealer and have the car picked up. Went back to the stock cap and never had another problem. Figure if someone really wants to steal gas, they will just bust it off or drill a hole in the tank.

 

This 5504 I bought seems to twist on perfectly every try. So far so good.