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Posted

I would hook up a scanner and drive your daily routine and record live data. Then go over it and look for any misfire data on each cylinder, air flow data, fuel trim long and short term. I would do it twice once with it going from 4 to 8 cylinder and then with it disabled.

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Posted
On 7/14/2017 at 4:21 AM, lloydsmale said:

there is a service bulletin and a computer reprogram that takes care of this. At least in the case of the 17s. Mine did the same and after reprograming it went away. It is your torque converter lockup kicking in and out.

Can you provide any more details? What info can I give to the dealer?

Posted

My 17 does this! 2-3 it bogs then catches, feel like the truck is tethered then the tether breaks. I’m going to mention this when it’s time for my first oil change. 

Posted

Haven't chimed into this thread in a while, but I actually had a blow out on my tranny last week. Picked the dog up from the vet and just trying to merge into traffic, rpm start flaring, hard engagement into gear, slipping, lunging, etc. Barely made it home to drop the pup off and limp to the dealership. Haven't got a full diagnosis yet. Hope to hear more by tomorrow.

  • 6 months later...
  • 3 weeks later...
Posted
On ‎8‎/‎20‎/‎2015 at 12:27 PM, Mike Robinson said:

Hello Everyone!

 

First off I have a 2015 Silverado 5.3 4wd. So when I first brought the truck home after about 50 miles I developed a misfire. I brought it in and they found a bad spark plug and bad coil. This has been great until about 2k miles later and I started to develop what I thought was it cutting throttle after it shifts, shifts drops into 1700 RPM range stutters then and gives a misfire type feel. Bring it in and told it was the torque management system doing what its supposed to. I accepted this and kept driving it.

 

After this last weekend I had the opportunity to drive it 200+ miles at speeds of 70-75 mph and what I noticed that the same hesitation/misfire would occur if I give it a certain amount of gas at that speed. At this speed the RPMs were right in that 1700 RPM range that I was noticing the "Misfire" after a shift. Well after coming back down to speed it would consistently happen happen while accelerating from a dead stop at a "normal" pace. This was after running the ruck for 2 hours on the highway. No CEL. So I take it back to the dealer to get some service done and have them to explore this again...The answer I get was they could not replicate the issue and the only thing they think it may have been is the transition between 8/4 cylinders and since I don't have exhaust flap I may be noticing it more, I have an aftermarket exhaust. This was after 2 days and the shop foremen driving it home for the night and back the next morning. Which my response was the truck was in here prior to the exhaust and know what the transition feels like, and what is occurring is disruptive and can be felt by everyone in the vehicle. Of course at this point there isn't anything they can do since they can't replicate it and there is no code. They want me to drive with a tech to see if its my driving style. I had 2 others drive it and it happened to them too...

 

So not sure what to do or what it can be...everything points back to ignition/fuel in my mind since it had issues from the factory.

 

 

What you guys think?

I love how their first diagnosis is always aftermarket parts. I have similar symptoms and asked them to check it out at my first oil change last week. They said they couldn't replicate it but that they noticed I installed an Airaid intake tube and said it was probably getting too much air... C'mon now!

Posted

I am having same issue with 2018 not a problem with my 2014. Took it to dealer first oil change and had them look at it they pretty much did the same song and dance blaming tranny program. It's a 6 speed 5.3 4 wheel drive almost the same setup as my 2014. I agree Bash74 you probably will need to hook it up to scan and drive it. It won't flash a code because its to short of time. 

  • 1 month later...
Posted

i am having same issue with 2015 chevy silverado hesitation during acceleration.

  • 7 months later...
Posted
On 7/14/2017 at 5:21 AM, lloydsmale said:

there is a service bulletin and a computer reprogram that takes care of this. At least in the case of the 17s. Mine did the same and after reprograming it went away. It is your torque converter lockup kicking in and out.

Do you happen to have the TSB# for this?  My truck (2018) is doing something similar to this.  When it is acting up, I can hear a sputtering, whomping type sound from the drivers side.  I have been searching this forum for an answer and have found different solutions from different people all with seemingly similar problems.

 

These are the possible solutions I've seen thus far:

  1. Loose exhaust clamp that is near the catalytic converter
  2. Bad vacuum pump
  3. Bad steering column/firewall seal
  4. Torque converter locking up (this thread)
  5. Exhaust flapper valve (I have mine permanently open which stopped the ticking sound I was hearing at idle...it sounded like a loose heat shield)

I also suspect that it may be AFM related based upon other things I've read.

 

I drove into work today in "L5" to keep the AFM from turning on.  The issue I'm experiencing was seemingly absent.  I'll pay attention on the drive home today and see if its still gone.  If so, I may just disable my AFM.  I'm not a fan of taking my truck to a dealer and letting a technician drive it all over tarnation hoping to find some intermittent problem.  My past experience with dealerships is if you want results, you have to arrive armed with all of the information that you can gather to avoid being given the runaround.

 

I must admit, I pretty annoyed with a new truck doing this with less than 2000 miles on it.

 

  • 2 months later...
Posted

Ok, I have a 17 3500 chassy cab savana with a reading box,l96 and 6l90. I have the same exact issue since new 40k miles ago. Even with the other member saying in hotter air temps it worse. Even the weird up shifts. My 15 1500 5.3 seirra does this but it's almost un noticable...almost.. 

I have a Diablo t1000 tunner I use as a gauge pod in the savana. When this issue is happening the ignition timming is low in the. Single digits and fuel trims sometimes go to near 10% negative and positive. Usualy not the 20%full swing.. No knock retard on the gauge. I was thinking its fuel /ignition related...when its runs good. I see great timming and only a 4 to 6 % swing in fuel trims. And no hesitation. The dealer said it was the torque converter slipping in and out 'as designed'. Well he was wrong. He did a live test scan when I was driving and it was in a solid lock up with zero slip while it was happening. Then he had no other comment on the hesitation feeling. Black bear tunning is my next step. They will do a data log and make a tune for  the savanna since there is none out there.  

Anyone have any other updates?

Tom

  • 3 weeks later...
Posted

Anyone find a solution to this issue? I have a 2016 5.3 Z71 with 72k. Starting having a similar issue this week while accelerating around 20-25 or 50 mph I can feel sputtering or jerking sensation. I initially thought I got bad gas but injector cleaner and 2 tanks of high test later same issue.

  • 3 weeks later...
Posted
On 6/5/2019 at 10:46 PM, Tab686 said:

Ok, I have a 17 3500 chassy cab savana with a reading box,l96 and 6l90. I have the same exact issue since new 40k miles ago. Even with the other member saying in hotter air temps it worse. Even the weird up shifts. My 15 1500 5.3 seirra does this but it's almost un noticable...almost.. 

I have a Diablo t1000 tunner I use as a gauge pod in the savana. When this issue is happening the ignition timming is low in the. Single digits and fuel trims sometimes go to near 10% negative and positive. Usualy not the 20%full swing.. No knock retard on the gauge. I was thinking its fuel /ignition related...when its runs good. I see great timming and only a 4 to 6 % swing in fuel trims. And no hesitation. The dealer said it was the torque converter slipping in and out 'as designed'. Well he was wrong. He did a live test scan when I was driving and it was in a solid lock up with zero slip while it was happening. Then he had no other comment on the hesitation feeling. Black bear tunning is my next step. They will do a data log and make a tune for  the savanna since there is none out there.  

Anyone have any other updates?

Tom

Update. Just ordered the Black Bear autocal.. Can't wait!

  • 2 months later...
Posted
On 7/6/2019 at 11:52 PM, Tab686 said:

Update. Just ordered the Black Bear autocal.. Can't wait!

Ok. Did a custom tune to the trans and engine. All I have done to the motor is a k&n filter element. The engine is so much more responsive and runs great. The trans tune was set from locking up in 2nd at 1800rpm wth the factory tune under a light load to late in 4th gear. Also it holds each gear longer before the shifts. What i did notice is once it is in lock up i now know what i was feeling as per the hesitation. If i log the rpm in lockup  up a slight hill or any but hold that speed i notice the prm's jump from one number up and down 40 to 60 rpm. Its not a calculation error due to i can hold the rpm in a non lock up situation almost to 0 fluctuation. I emailed black bear and they are going to look into the tune and see if it it calling for 100% lock up or not. I will give updates as they come in.  Hope this helps someone else.

 

  • 3 weeks later...
Posted

This is exactly what my 2014 is doing. Just kinda started out of nowhere. I find if my truck is warmed up it doesn’t do it. But, everything all of you are talking about is what I am experiencing. This is an old thread so I am wondering if anyone ever found the actual solution. There is no codes at all.

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