2008 Aveo5 LS 1.6L dying going down the highway

[furface1951]

Hi, people, glad to be on here amongst such knowledge on the Aveo's. My wife's Aveo dies at highway speeds, she pulls over and lets it sit for a minute or so and then it starts back up. It might go for a month or more before it does it again, but on 01-18-2012 it died 7 times. I took it to a dealer and had them scan it and all that showed was a 02 sensor problem. Could that be it? I put a can of injector cleaner in the gas on 01-20-2012 and it hasn't died yet......maybe a partially clogged injector? It is hard to tell if that is the problem since the problem is so intermittent. Please help while I still have hair............lol.

[Daox]

The O2 sensor is not the problem. The engine will run without an O2 sensor, just not as well and won't pass emissions. It also not a clogged injector. If it were that you would notice rough idling, but it wouldn't just die.

If I were you I'd try to get the dealer or shop you go to to use the car for a day or two to see if they can get it to do it. Intermittent problems are so annoying to figure out without a engine light to tell you something.

Is there anything else you can tell us about how the car dies? Certain times? During acceleration/deceleration? Anything helps.

[furface1951]

Thanks for replying. My wife is a traveling nurse and she needs her car everyday and she doesn't want to use my Silverado......lol. The dealership had it for a day early this week and drove it, but it wouldn't act up for them......go figure,huh? It dies when going down the highway at steady speed. It idles nice at stop lights, warm ups in the garage every morning and idles fine. Too bad there isn't a portable scanner they could hook up and let her drive it and when it dies it would record it....kind of like a black box on a airplane.

[Daox]

Have you had any work done on it recently? How many miles? How long since the last bit of maintenance (spark plugs especially)?

[furface1951]

No, Daox, just plugs last Fall along with a new serpentine belt. It has 60,000 miles on it. Wife has the oil changed every 3,000 miles religiously

[charlieb]

i had a loose crankcase sensor that was loose once that would cause intermitten problems eventually was discovered when i had vehicle towed to shop(chev 3.8 v6) it would run fine for 3 months than not run for 1-24hrs then run great but doent seem like your problem.my first guess would be like a crimped/ bad electrical wire or sensor causing either no spark or no fuel(1 or the other) but because it is intermitten you could be searching forever and impossible to diagnose(unless you get lucky)until its completely broken.EVEN A BROKEN CLOCK IS RIGHT 2 TIMES A DAY.

[furface1951]

Thanks Charlieb for your input, but I don't think it is the same problem. I am at my wits end on this problem. I am thinking it is electrical like a coil pack or maybe a fuel problem like a fuel pump. Heck it might even be a gas cap problem. I am just grabbing at straws at this point............

My Dad always said, "when it breaks down, Look at the last thing you fixed".
Well, it has never been worked on for 60,000 miles, so much for my Dad's theory,huh?

[jriggs87]

I think your right when you suspect a fuel delivery problem. since it was scanned and didnt read any codes suggesting ignition problems, I would think the next possible thing would be fuel. cant be timing because its an intermittent. A wild guess... since it drives well in city miles, where the gas is being used on and off, the fuel pump or maybe just a clog somewhere is preventing enough gas to be injected into the engine when your wife keeps the pedal in a constant place. but like you said as well, if its fuel it could be a whole buncha things. (gas cap, filter, pump, etc...) good luck, youve got my attention on this one. as much as I cant stand or trust some dealership mechanics, i agree with charlieb, let them have it for a while until it happens to them.

[petrified.rabbit]

The O2 sensor is not the problem. The engine will run without an O2 sensor, just not as well and won't pass emissions.

Not to say your wrong, because 99% of the time that is the case, but my aveo would not run at all and it was the o2. Put the new one in and it ran great.

OP: Based on your brief description, I am going to say, if it only happens on highway and that infrequently. I would suspect an issue with egr, or the evap purge. You would need to see (probably with the dealer) what condition activate those two systems, but it is usually cycled on during cruising speeds after warm up. Additionally from your description, i honestly suspect the evap, as it sounds like it is depressurizing the fuel system when the system purge valve opens.

but thats just an internet diagnosis.

[furface1951]

Petrified. rabbit..........you gave me a good idea on the evap. I will check it out. I will let you all know what I come up with