Jump to content

Shaking like a 70's car at a stop light.


Recommended Posts

I'm curious as to what idle speed you are seeing when you get the shake? Is it lower than normal? Because if the engine cannon hold "target idle speed" there is a problem, period! I'm assuming the dealer is plugging in their scanner and verifying this.

 

My 6.2 has no shake, I would bet I can bring it down to 400rpm idle and still have no shake

 

 

Sent from Off Driller Side

 

when the truck idles at 500rpm's or above you don't fill anything but sometimes it starts dropping below 500 and thats when the truck starts to shake. I bring rpm's up and it goes away. Its a simple fix but dealer says thats the way it is that if no check engine light comes on they can't do anything.

Link to comment
Share on other sites

  • Replies 61
  • Created
  • Last Reply

You do realize it has a 6.2 liter lump of AL pushrod American V8 muscle thumping under the hood right?

 

The cam profile on these trucks aint like a mini 5.0 or 5.3 or V6, are you sure you're not just feeling the motor do its thing?

 

My LS1 GTO, L76 G8, LS6 Z06 all do the same. My 5.3 truck did not, my 6.2 truck does somewhat. Runs fine, definitely not misfiring.

Ive owned diesel trucks and you feel engine vibration, thats normal but this truck shakes when rpm's go under 500. Does it about 60% of the time when stopped at a stop light..

Link to comment
Share on other sites

 

I'm wondering if this may be related to a carbon buildup issue. Is anybody here with the issue running catch cans?

It's a stretch but If somebody here would do a BG top engine cleaner or at least run a can of seafoam through the intake and report back, you may see some positive results.

 

If anybody in Tulsa area is experiencing this, please PM me. I would like to scan your truck while it does this and get some data.

 

 

Sent from Off Driller Side

Link to comment
Share on other sites

Ive owned diesel trucks and you feel engine vibration, thats normal but this truck shakes when rpm's go under 500. Does it about 60% of the time when stopped at a stop light..

Target idle speed is 550 rpms. If it drops below 500 you have a problem wether it be bad fuel, plug, wire, coil, lifter, etc. and any GM tech should recognize this.

 

 

Sent from Off Driller Side

Link to comment
Share on other sites

Target idle speed is 550 rpms. If it drops below 500 you have a problem wether it be bad fuel, plug, wire, coil, lifter, etc. and any GM tech should recognize this.

 

 

Sent from Off Driller Side

I Know, but dealer response is if check engine light does not come on it's fine. with ac on it stays at 500 and starts dropping and correcting it's self, thats when the shaking starts.

Link to comment
Share on other sites

2014 Sierra Denali 23k miles and every-time you stop at a light RPM'S drop a little below 500 and it starts doing the shake! Anyone with this same issue? 3 dealers and response is they are all like that? contacted GMC and no help at all, premium fuel and nothing.

 

Time to change the truck i guess.

 

 

Hi jpmiami and everyone,

 

We understand how this issue can be frustrating and would be more than happy to assist you by looking into this further. If you're experiencing any shaking we encourage you to send us a private message with your contact info, VIN, mileage and preferred dealer. Once we receive the requested information via private message we'll be able to reach out to your dealer for clarification and research. We're here if you need us.

 

Sincerely,

Eddie A.

GM Customer Care

Link to comment
Share on other sites

I Know, but dealer response is if check engine light does not come on it's fine. with ac on it stays at 500 and starts dropping and correcting it's self, thats when the shaking starts.

Wish I could help you, but I sure as heck wouldn't ignore it.

 

Edited: Looks like GM is interested in helping you fix this. Good news

 

 

Sent from Off Driller Side

Link to comment
Share on other sites

 

Hi jpmiami and everyone,

 

We understand how this issue can be frustrating and would be more than happy to assist you by looking into this further. If you're experiencing any shaking we encourage you to send us a private message with your contact info, VIN, mileage and preferred dealer. Once we receive the requested information via private message we'll be able to reach out to your dealer for clarification and research. We're here if you need us.

 

Sincerely,

Eddie A.

GM Customer Care

Info sent.

Link to comment
Share on other sites

I Know, but dealer response is if check engine light does not come on it's fine. with ac on it stays at 500 and starts dropping and correcting it's self, thats when the shaking starts.

Find another dealer.

Link to comment
Share on other sites

Just picked up my brand new 2015 Sierra Denali....truck fluctuates like crazy at idle (2-300 rpm's).....called the dealer and service said it was normal for GMC's and has been a problem.....not sure what to do....

Link to comment
Share on other sites

Just picked up my brand new 2015 Sierra Denali....truck fluctuates like crazy at idle (2-300 rpm's).....called the dealer and service said it was normal for GMC's and has been a problem.....not sure what to do....

Take it to another dealer if possible.

Link to comment
Share on other sites

Just picked up my brand new 2015 Sierra Denali....truck fluctuates like crazy at idle (2-300 rpm's).....called the dealer and service said it was normal for GMC's and has been a problem.....not sure what to do....

2-300 rpms seem excessive but just in case and I'm not sure how many miles you have on it but if brand new I would put a couple hundred miles on it in case the fuel trims are still stabilizing. After that, I'd park it in their lot and say fix it. My 6.2 Tach needle is rock solid.

 

 

Sent from Off Driller Side

Link to comment
Share on other sites

Well after 40 miles (110 total) the truck threw a CEL and I limped in to the dealer this morning with a definite problem....OnStar says engine misfire.....the truck was not running good....no word yet on the problem....Day 1 with my first GMC did not go well.....

 

Edit....Dealer called....a clip on one of the spark plugs came loose and fell off...she said that the clip coming loose was likely causing the cause in my RPM flucuation yesterday and it finally gave....they changed all the plugs and wires and are driving the truck to me to swap out the loaner.....all is good and excellent service from the dealer....S*&t happens and they handled it well.....

Link to comment
Share on other sites

Well after 40 miles (110 total) the truck threw a CEL and I limped in to the dealer this morning with a definite problem....OnStar says engine misfire.....the truck was not running good....no word yet on the problem....Day 1 with my first GMC did not go well.....

 

Edit....Dealer called....a clip on one of the spark plugs came loose and fell off...she said that the clip coming loose was likely causing the cause in my RPM flucuation yesterday and it finally gave....they changed all the plugs and wires and are driving the truck to me to swap out the loaner.....all is good and excellent service from the dealer....S*&t happens and they handled it well.....

Good news

 

 

Sent from Off Driller Side

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.




×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.