Your driving a high compression Atkins Cycle Lean Burn Engine. I understand this engine may fire two cylinders at a time for better low rpm performance.

No doubt with the 13:1 compression and it being designed for a very lean burn. The quality of 87 octane gas you buy would be most important.

If you have used a discount stations gas it may take two or more tanks of gas to get it cleared out. I made the mistake of buying some walmart gas once.

Its' best to always use a brand of gas listed on this page below.

open the link to, Retailers when the page opens.

www.toptiergas.com/

 

I unfortunately have the same issue as you guys, I didn't know what to call it when I started a new topic and I stumbled across your topic. Unfortunately, I guess you guys don't have an answer to it either! If I run Chevron or BP regular, it seems to run much better than shell, walmart, sams club, or sunoco gas. Its annoying but I seem to be learning to live with it. Let me know if you guys happen to have a fix for this annoyance.

Here's a link to the topic I started:

https://www.greenhybrid.com/discuss/...0-35mph-27705/

 

I am now at close to 200,000 miles and the car still runs like brand new. It still pings in the summer but not in winter. There are a couple of things I have tried that have helped a bit.
At 192,000km I had the spark plugs replaced and the pinging disappeared for about 50,000 but then came back. At 300,000km I asked the dealer about it again and he suggested a fuel system flush instead of changing the plugs early. That helped a bit and actually increased my mileage.
My conclusion is that these engine are run very lean and that they run too lean when hot. There is nothing to change on them. When I have pinging issues I use mid grade or higher and it goes away. It doesn't make any difference if I use top tier gas, in some cases it's worse.
I tried disconnecting the battery to reset the computer but that didn't help.

If you live in a hot climate try changing the plugs early and see if it helps. If not the only solution I know of is higher octane gas.
The higher cost of gas for the summer has far been outweighed by the incredible reliability. It still drives like new and still gets great mileage. The only thing I have ever done is changed the brake pads when they wore out at 240,000km. The extra brake jobs on a normal car would have cost more than the difference using high octane gas. The battery system still seems perfect. For that kind of bullet proof performance I don't mind the extra cost in higher octane when I need it.

For those interested, my lifetime gas mileage average is 6.3l/100km or 37.4 US mpg. It hasn't changed much other than when I had the system flushed it improved a bit. My driving is a fairly even mix and I don't drive slow. In fact unless you want to drive like a granny there is little to be gained by babying the gas pedal, the increase in mileage is minimal.

 

A year before I traded my '07 TCH I had a pinging problem. My wife noticed it one night as we were driving up on the railroad overpass in the south end of town. She heard it as the windows were down some to let the cool air to come in the cabin. Their was a concrete protection wall about 6 feet to the right side of my car and was reflection off of that.

It took me the next tank to figure what the problem was. I had been using Chevron a top tier gas and had switched to the Texaco truck stop in the north end of town. It's also a top tier gas and they had rebuilt the pumps and installed the new fiberglass underground tank at that station. I somehow ended up with a bad batch of regular gas in my tank. I tried some additives (bottle of techron in one tank and Lucas fuel injector cleaner in the others) which helped if I didn't crowd the accelerator.

I started using the Phillips 66 multi-pump station located in a popular grocery store parking lot. I once talked to the tanker driver and he said they used 8000 gallons a day and get the gas from the El Paso refinery, 80 miles away. It took me 3 full tanks to get the ping out of my engine. I didn't think it was the engine as the car only had about 30K on the clock at the time. It was my wife that mentioned the only change I made before the pinging was me switching brands of gasoline.

 

My wife owned a used low miles '99 Ford Ranger pickup. It had the famous Ford 3.0 V6 then used in years of their Ford Taurus cars. Many of these engines were FFV for flex fuel vehicle. It suppose to run good on flex fuel. Well come to find out on the internet that the engine pings when climbing a overpass even when using top tier gas. It's just a built in engineering problem. The service dept was quick to replace the expensive fuel filter which didn't help at her truck at all. Some I read where many had replaced all 6 fuel injectors which was costly and that didn't help either.

My point here is my wife found when she mixed her gas half regular and half mid-grade the problem went away.

My wife don't let her tank get below 3/4 when she fills it again. So by doing this she found she could fill one time with regular the next time with mid-grade. This way it's mixed all the time. This would be cheaper than just buying the mid-grade all the time, if the mix gets rid of the pinging.

 

I would stick with the www.toptiergas.com/retailers.html brands of gasoline. I noticed the only top tier brand you mentioned in your message was Chevron. Chevron a excellent gas were I live. It's usually higher priced than the other top tier brands in our area. I found on the TT list brands that were 5 cents per gallon cheaper. Then I discovered the multi-pump Phillips 66 station located only a few blocks from a no-name discount station. The Phillips station is usually only 3 cents per gallon more than the discounter. The phillips sometimes is a full 10 cents cheaper per gallon than the Chevrons and I can't tell any difference in the performance or mpg either. I also found out from the Conoco/Phillips homepage that Phillips uses the same techron from techron chemicals, the same as the Chevron brand. I should mention Phillips does rename their special additive, same name change for Texaco and Shells to add more power and mpg for you driving experience.

Top Tier won't work with the large chain store sellers as they use various brands of gasoline, usually the low bidder. I found many years ago a popular no brand station at a then large FedMart outlet. I knew the station manager and he said they used Shell a mostly but also bought gas from Fina and Diamond Shamrock. I found this was why some tanks my car would ping if I got on it. Back then I was running my ignition timing rather high to increase my mpg and was critical on the quality of gas I used. I don't know how Costco buys their gas but most seem happy with it.