[miamialley]

Had my 2016 since 12/2016 and have experienced this issue ever since. 21,000 miles on the car, only 1,500 ICE miles. Had Chevy look at a year ago, said it was normal. I know it's not. I'm having them look at it again. If it happens, it happens at the exact same time the ICE engages, no other times.

Anyone have the issue?

Update: see Chevy forum response in replies below. They explain the noise is normal, but can't say what makes the noise or why the noise is made.

 

[Arcanox]

Had my 2016 since 12/2016 and have experienced this issue ever since. 21,000 miles on the car, only 1,500 ICE miles. Had Chevy look at a year ago, said it was normal. I know it's not. I'm having them look at it again. If it happens, it happens at the exact same time the ICE engages, no other times.

Anyone have the issue?

It's the engine backfiring; it happens to most Gen 2 owners. Despite how ridiculous it sounds, it is "completely normal".

Half the Gen 2 owners on the forum are waiting for GM to find a fix for it but they don't seem too motivated to do so. I use my ICE every day and it does this almost every time it starts.

 

[SharkVolt]

Could it be engine knocking?

If so, try better gas (or higher octane)

 

[quirkySquirt]

miamialley, SharkVolt, you can see what I think is the same problem in this thread:

http://gm-volt.com/forum/showthread...ming-from-rear-passenger-side-2016-Chevy-Volt

OP from that thread uploaded a Vimeo video that perfectly catches multiple instances of this issue. I'm still having it but haven't found the time during recent warmer temps (along with time off) to bring it to the dealer. Nearest Volt Techs for me only work weekdays so makes it hard to drop off and go for test drives.

I think in Arcanox's case, temperature was not a factor but in my case, whenever outside temp fell below 40F, I never had the backfire sound. Once above 50F, always have it. Inbetween, depends on how hot the engine becomes and how hard I accelerate. I've tried variety of gas from Fred Meyer (Kroger), Safeway, Chevron, Shell, and 76 to no success. I've only tried each once side from Safeway as I only fillup once about every month.

I also thought my recent oil change and recall for updating the "motor power inverter module" fixed things, but alas, temps were 45F that day so I was mostly getting no backfire until the engine finally warmed up to 190F.

Other users who may be experiencing this same problem:

http://gm-volt.com/forum/showthread.php?261057-16-Volt-backfiring
http://gm-volt.com/forum/showthread.php?227073-Clank-noise-when-on-ICE-and-making-right-turn

 

[caronjeff]

Wonder if anyone has tried no-ethanol gas. 100% gas without blended in ethanol is available, you have to search for it. Would be an interesting test. The video clearly shows backfire, meaning unburned fuel ignited in the muffler.

 

[Raymondjram]

Had my 2016 since 12/2016 and have experienced this issue ever since.

If it is a metallic "clank", then have the exhaust system inspected for loose or broken hangers or brackets. An engine backfire should not sound like a clank. Ask a volunteer to listen to the sound correctly (or better, record it) when it happens and to observe the tailpipe. If the pipe moves, then it is a mechanical issue.

 

[jsmay311]

miamialley, SharkVolt, you can see what I think is the same problem in this thread:

http://gm-volt.com/forum/showthread...ming-from-rear-passenger-side-2016-Chevy-Volt

[...]

Other users who may be experiencing this same problem:

http://gm-volt.com/forum/showthread.php?261057-16-Volt-backfiring
http://gm-volt.com/forum/showthread.php?227073-Clank-noise-when-on-ICE-and-making-right-turn

https://vimeo.com/177954038

WOW! I had missed those earlier threads.

How in the F does GM have the balls to say that this is "normal"?

Is there any indication that this has been fixed in newer vehicles?

 

[jupitermoon]

You guys should be happy it sounds like a Audi RS with DSG transmission upshift pops. Just kidding.

The other day my car's maintenance mode kicked in for the first time...a month into ownership. You can really feel that engine kick in....it's not as smooth as one claims it to be and man...it really makes you appreciate EV's more.

 

[caronjeff]

My 2011 Volt with 92,000 miles, when the battery charge runs to minimum and the ICE starts, you hardly even know it's on. This is making me rethink my desire to purchase a Gen 2 Volt! How rampant is this problem? One definitely cannot put up with an engine backfire! Unacceptable under any circumstance.

 

[miamialley]

I got this private message as a response to this thread today:

"We came across your post on the forum, and though we recognize you're seeking advice from other users, we did want to weigh in with the information we have from our end as well. Our internal technical resources here at GM have advised us that this is in fact considered to be a normal operating characteristic. We understand this isn't the answer you were hoping for, but we wanted to reassure you that your Volt is considered to be operating as normal.

If you have any questions or concerns, please feel free to let us know."

Kindly,
Lauren E.
Chevrolet Customer Care

 

[quirkySquirt]

You guys should be happy it sounds like a Audi RS with DSG transmission upshift pops. Just kidding.

The other day my car's maintenance mode kicked in for the first time...a month into ownership. You can really feel that engine kick in....it's not as smooth as one claims it to be and man...it really makes you appreciate EV's more.

My 2011 Volt with 92,000 miles, when the battery charge runs to minimum and the ICE starts, you hardly even know it's on. This is making me rethink my desire to purchase a Gen 2 Volt! How rampant is this problem? One definitely cannot put up with an engine backfire! Unacceptable under any circumstance.

I have mixed experience with the ICE. When cruising at a steady speed of 60MPH and I notice the energy consumption is below 15kW, the transition to ICE is pretty smooth. You can still feel it, only once did I not feel it at all and was surprised to start hearing the ICE. If consumption is above 15kW (e.g., you're going up hill even at constant 60MPH), then I can feel the ICE transition jerk my Volt. When I cruise at 30-40MPH, the energy consumption has to be below 7kW for a smooth ICE transition, other wise I feel a jerk. I plan on complaining soon when it gets really hot. I'm hoping to get a Volt or Bolt loaner (even if the Bolt seats are thinner, which I can confirm they are) during spring. I really don't want an ICE loaner but this is likely what they'll give me. This is the only thing deterring me from taking it in for fear the shop may try to diagnose the issue even though they know it's normal to backfire. I don't want to go back to driving an ICE.

miamialley, I too got the same response and was urged to take it up with my dealer if I really felt it was an issue. In other words, it might be just a waste of time.

 

[quirkySquirt]

If it is a metallic "clank", then have the exhaust system inspected for loose or broken hangers or brackets. An engine backfire should not sound like a clank. Ask a volunteer to listen to the sound correctly (or better, record it) when it happens and to observe the tailpipe. If the pipe moves, then it is a mechanical issue.

Do you think the sound in the other thread:

http://gm-volt.com/forum/showthread...ming-from-rear-passenger-side-2016-Chevy-Volt

is metallic? Cause mine sounds exactly like that. If it is mechanical, how come during the winter with temps below 40F I can never get the sound again no matter how long I run on gas (both in HOLD and CS mode) and how hot the ICE gets <40F ambient? Wouldn't a mechanical issue still be present during cold temperatures? Just today it was 56F outside and I could get the backfire to sound almost 75% of the time.

 

[Scruffy]

After reading this post and earlier related posts about this exhaust noise problem, all of the posters but one, are from CARB compliant States. Just to ask, is this issue mainly with CARB volts. Are the emission standards drastically different with the nonCARB volts?

 

[Hornskeith]

After reading this post and earlier related posts about this exhaust noise problem, all of the posters but one, are from CARB compliant States. Just to ask, is this issue mainly with CARB volts. Are the emission standards drastically different with the nonCARB volts?

All the cars listed on dealership sites from CARB states list Low Emissions Package (T-ZEV) in their options list, so it's at least possible. But lots of Volts are also sold in CARB states due to the incentives.

FWIW, my non-CARB Virginia Volt doesn't have this behavior, but it was also built last December.

Keith

 

[Arcanox]

All the cars listed on dealership sites from CARB states list Low Emissions Package (T-ZEV) in their options list, so it's at least possible. But lots of Volts are also sold in CARB states due to the incentives.

FWIW, my non-CARB Virginia Volt doesn't have this behavior, but it was also built last December.

Keith

My Volt was originally sold in California. That's a good observation...I really wish GM engineering would stop saying this is "normal" because I've never seen or heard of any other hybrid backfiring when the engine starts.

 

[jsmay311]

Between the backfiring and the chuggle, it's hard to understand how GM Engineering can be struggling so much with such seemingly-ordinary engine issues on Gen 2.

 

[quirkySquirt]

Wonder if anyone has tried no-ethanol gas. 100% gas without blended in ethanol is available, you have to search for it. Would be an interesting test. The video clearly shows backfire, meaning unburned fuel ignited in the muffler.

I'll look into it. I thought this type of fuel is typically found at marinas where boats typically need 100% gas.

After reading this post and earlier related posts about this exhaust noise problem, all of the posters but one, are from CARB compliant States. Just to ask, is this issue mainly with CARB volts. Are the emission standards drastically different with the nonCARB volts?

Huh, this could be it. I don't recall seeing the T-ZEV package that Hornskeith mentioned, but plugging my full VIN # in I noticed that it has the "Emissions, Federal Tier 3" listed. I used the VIN decoder from chevroletforum.com/forum/vindecoder.php and went to the "Equipment" tab.

If this were the case, is there no way we can have the T-ZEV package removed or tweaked? I find it hard to believe that other vehicles with a T-ZEV package have a backfire sound.

EDIT: Just checked a listing for a Volt here in Washington and noticed the Volt has following options installed:

California ULEV125 Emissions Requirements
Northeast Emissions Requirements (Includes Connecticut, Delaware, Maine, Maryland, Massachusetts, New Jersey, New York, Oregon, Pennsylvania, Rhode Island, Vermont and Washington state requirements.)

We should start a poll about this with options like: a) my CARB Volt backfires b) my CARB Volt runs fine c) my NON-CARB Volt backfires d) my NON-CARB Volt runs fine.

 

[Arcanox]

I'll look into it. I thought this type of fuel is typically found at marinas where boats typically need 100% gas.


Huh, this could be it. I don't recall seeing the T-ZEV package that Hornskeith mentioned, but plugging my full VIN # in I noticed that it has the "Emissions, Federal Tier 3" listed. I used the VIN decoder from chevroletforum.com/forum/vindecoder.php and went to the "Equipment" tab.

If this were the case, is there no way we can have the T-ZEV package removed or tweaked? I find it hard to believe that other vehicles with a T-ZEV package have a backfire sound.

EDIT: Just checked a listing for a Volt here in Washington and noticed the Volt has following options installed:

California ULEV125 Emissions Requirements
Northeast Emissions Requirements (Includes Connecticut, Delaware, Maine, Maryland, Massachusetts, New Jersey, New York, Oregon, Pennsylvania, Rhode Island, Vermont and Washington state requirements.)

We should start a poll about this with options like: a) my CARB Volt backfires b) my CARB Volt runs fine c) my NON-CARB Volt backfires d) my NON-CARB Volt runs fine.

I've got "Emissions, Federal, Tier 2" and I get the backfire regularly. My car was originally sold in California, so I would assume it absolutely is CARB-compliant.

 

[KenC]

December build, Carb-compliant and no clank.

 

[miamialley]

Got a response back from Chevy via this forum:

"Thanks for your patience as we looked into this further. Unfortunately, we're unable to speculate as to why all Volts don't experience the noise. This is because there are many usage factors to be considered that might cause some drivers to observe the noise, while others do not.

We apologize in advance for not being able to provide additional insight on this. However, we want to again reassure you that this is nothing out of the ordinary, as the noise is considered to be a normal characteristic. If you have any additional questions, please let us know."

___

So, they say it's normal, but won't say what it is or why it does it.