Hmm... I have the same problem with my 2009 Impala LS. Mine has 24,000 miles on it. No other problems, just this one.
Anyways, same thing. Dealership says it's fine and not to worry too much. Really? These American companies expect us to "Buy American", but when something goes wrong with one of their cars, they ignore it. I was told that it has something to do with worn out plastic gears in the electronic throttle body.
I agree. Higher octane fuel won't make a car run better. That's been a long time myth. High octane is for high performance engines to eliminate the knock because it burns slower. A car designed for 87 should run fine on regular gas.
You have a car that is less than a year old and still under the manufacturer's warranty. You need to be more persistent, and as someone else pointed out, go to another dealership. Contact GM if necessary. There is no reason you should have to put up with this, because the techs can't figure it out, and you need to let them know that.
What do you expect? We have posters on this site telling people to put black tape over warning lights, because they mean nothing, and they are just a ploy to get more business for the dealer service department. Why would GM feel obligated to actually fix a problem like this, when so many seem to ignore their own vehicles when problems arise?
Why people continue to support GM is beyond me, but the expectations are set so low, it seems they do sell their vehicles. It is funny that the average GM driver is a mechanic who knows a lot about cars, or they ignore any problems and write them off as "not a real problem"...
No thanks. I like trouble free driving!
(Original poster replying here)
Well, it's going back to the dealership. Someone instructed me to pull the accordion tube off (engine off, key off) between the throttle body and the air box, manually open the throttle plate and wiggle it. If it has play in it, it needs replaced. Apparently even a minute amount of play in the throttle plate will cause idle issues. The good thing is I know how to work on cars, and doing this was no big deal for me.
On the bright side? It seems that DBW throttle body issues happen across the board... even on imports. It's not common, but it does happen.
Anybody want to bring up the poor fuel quality? Ethanol at up to 10 percent. There has been various discussions, especially marine usage over the past... I don't buy no name fuels, and over the years I have received bad gas and even water in my tanks. I try to buy fuel that cleans the injectors as you drive. Not just what is the rock bottom cheapest. I also use additives in my cars and boats.
Another factor is stale gas in vehicles sitting. I use Stabil. I also have a relative that fills his large Ram truck over the southern border, and although it may be cheaper there, I have to wonder what additives are there or are missing. I pay a little more at the pump, but I haven't had bad fuel.
Everyone should read owners manuals and get exact octanes to prevent detonating your engine. I ran 93 Octane in a Honda-Acura TL I owned. I always read manuals. I don't go cheap on gas where it's called out by manufacturers. Some say put regular in and drive lightly; that's a mistake if you need 93.
I always love it when I see the old "even on imports" addage. As if the Japanese know how to build cars that never fail. In all actuality, these days there really isn't much difference in the reliability of imports and domestics. A car is a very complex machine with moving parts, and whether manufactured in Detroit or Japan, it will eventually break. If you keep it serviced, it will last longer.
When I take long distance trips, I sometimes rent weekend specials from places like Enterprise. It's a chance to drive something different. If there's an issue, I go and get another car at the next location. But I have not had that problem yet.
I recently rented a new Impala, and would rent one again. It rode really well, and got very good mileage. It was quite easy to go well over the interstate speed limit if not watching closely.
It's not really very expensive to rent, and it's a great way to evaluate if you want to buy your own. I have rented ones with under 5000 miles on them. At any rate, I was quite impressed with the Impala. I drove all day, and was not tired with its nice ride.
You are contradicting yourself here. The first paragraph says you've had water in your gas, and the second says you've never had bad gas...
The Corvette is a poor testament to GM's overall quality. It is like saying the Viper is a gauge of Dodge's overall quality. They both are essentially hand built in special plants that have nothing to do with the regular mass produced vehicles that come from either company. This is why the Corvette and Viper are multiple times the cost of the average car. You really do get what you pay for.
Now if only GM and Dodge could have this quality across their entire lines like Toyota does... then you could brag about them.
Bragging about a Toyota is like bragging about your refrigerator. Both are boring, basic appliances.
Actually, I have followed Toyota's overall track record in recent years, and it's not been favorable.
I wouldn't brag about a car company with declining quality and millions of recalls.
Toyota still ranks above the domestics, EVEN with the recall circus the media used to try to destroy them! Keep drinking the Government Motors Kool-Aid...
The second paragraph I did not say I had bad gas. I would hesistate as my relative likes to buy the cheapest gas possible over the US border, which I question the fuel quality and additives or lack of there.
I buy Shell 93 as my personal favorite fuel. I like keeping the injectors clean as I drive. I do run injector cleaner in my cars that sit. If cars sit for a couple of months, the fuel can go bad; that's why I use Stabil and Startron, which address ethanol breakdown that can occur in a tank. I also keep my tanks filled to reduce condensation. 2 of my cars get less than 1000 miles a year usage, so I use the Stabil and Startron with no issues.
I have picked up bad fuel long ago by going to generic no name gas places. I also change my fuel filters at 30,000 miles. I also notice I get longer cat life as well.