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Problems/Service/RepairsIf you have a problem with your HHR, want a tip on repairing or performing a particular service to you HHR here is the place to post!
I have been getting the cylinder misfire on #1 code ever since a couple months after I replaced the OEM spark plugs. I guess I should have mentioned this earlier. I purchased my HHR about 2 years ago with 67k miles from a large Chevy dealership. I've always been kind of anal about maintenance on my vehicles. It now has about 73k miles on it, If I had to guess the original owner had run the cheapest gas they could buy in it since it was new. I contributed that to causing the black buildup on the plugs. My A/C had been Ice cold until the last week so this was the first time I needed to add any R134 to the system. I don't have any knowledge about the maintenance before I purchased it.
In the first 2 months I owned my HHR I replaced front and rear brakes w/ new drums and rotors. Flushed all the old brake fluid out of the system. Changed the transmission fluid and filter, Installed new spark plugs, replaced the engine and cabin air filters. Replaced the A/C -alternator serpentine drive belt and the front shocks plus the sway bar bushings. I just went thru all the basics so I knew what kind of vehicle I would be driving!
Tiapetra you have a good point about not replacing the a/c compressor right away. I have probably repaired 20 A/C systems over the years and never saw the Low and High pressures run so low when the system had close to the factory recommended freon charge in it. I just replaced a compressor on a 2008 F-150 3 weeks ago that had 175k on the original one. The way GM has the drier built into the condensers now it should most likely need to be replaced anyway when the compressor is replaced when it eventually dies so there's no hurry to tear into it right now. R134 is still cheap at $5.00 a can. I actually bought a couple of cases of 12oz cans about 3 years ago when a local Auto parts store had a sale on R134 @ $35.00 for a case of 12 cans!
If you tried to gap the plugs there is a good chance you broke a whisker. Don't do it!
Black plugs is bad, Should have triggered P0172 rich code. Maybe running too cold, but that should throw P0128 and disable the AC. Maybe leaking injectors.
The black spark plugs I mentioned were the OEM plugs I pulled out of the engine when I purchased it 2 years ago with 67K on them. No CEL's were set when I got it. I replaced them with fresh ones within 2 weeks of buying the car. The spark plug I pulled out yesterday to check that they were the correct number have about 7K on them. They still look pristine, I contribute the blackness to running cheap gasoline. Myself personally on use only TopTier gasoline. I normally only purchase gas from Exxon, Texaco, Shell, Chevron. I wouldn't use the crap from Walmart, 7-11, Racetrack and the like sells, not even in my lawn equipment.
I'm 99% sure I checked the gap on the new plugs before installing them. I really dought I needed to regap them though. Seems like the Mfg's have gotten so good in the last 20 years that I can't even remember the last time I needed to change what they came with!
DO NOT touch the whisker on iridium plugs!!!!!!!!!!!! You can't gap plugs without touching the whisker. They break very easily. I know; I wasted $25 trying to prove the experts wrong.
Iridium plugs are good for 100,000 miles.
At the tank farm all of the gas comes out of the same tanks and pipeline. You will see every brand truck in the lanes. The reason for multiple tanks is diesel,high octane, unleaded, aviation etc. The smaller tanks hold detergent and alcohol.
The differences are the additives and alcohol added at the filling rack by the truck driver. The frequency that the pump filters are changed does make a bit of difference, that varies by station, places like Costco have a very strict policy on changing them frequently. On the other hand I was unable to pump gas at an Exxon station because the filters had frozen at 20F. Unbranded vs. branded gasoline: Is there a difference? - The Barrel Blog
I would not blame cheap gas for the black plugs. It comes from too much gas in the A/F and/or incomplete combustion (misfire), not detergent or lack of (maybe dripping injector). If an injector was leaking you could check it by testing the fuel pressure retention after shut down. https://www.businessinsider.com/no-r...and-gas-2013-8
If you have a 2006 2.4L there is a TSB about the injectors and firmware needing upgrading.
In 1996 automotive engineering changed dramatically when OBD2 was mandated and minimum fuel standards were established and all underground tanks were replaced. Remember when "naturally aspirated" meant carburetted not injected?
People who are used to working on pre-1996 cars (us old farts) harbor a lot of wrong opinions on the subject when it comes to "modern" cars.
Thanks, DonBrew for all your input, I'll go back and check all the spark plugs in my HHR with a feeler gauge to see if any of the whiskers have any damage. I have a pretty good fuel pressure test kit so I'll test that and see if any pressure drop occurs. I really appreciate your suggestions!
