The Unexplainable, Unresolved issue an expert LS builder and Dealership can't figure out

[ivin74]

Update:
Dealership replace Evap Canister.
Didn't change a thing.
Convince me not to set this thing on fire and go get a Toyota something to haul kids around.
so sick of nobody able to diagnostic correctly the issue.

Did you ever do a pressure test on the coolant system and on the washer system. Sometimes you have to do the testing yourself. I have run into two issues in the past that the dealer could never diagnose nor fix, all they did was throw parts at it at my cost and believe me it was very frustrating a costly. I ended up fixing those items for less than 40 bucks. Those issues were not GM related but shows you how incompetent those mechanics are.

The first issue happened on my wife’s Nissan Sentra it started stalling out, out of the blue. The dealer changed all sorts of sensors and none fixed the issue. I ended up taking the air intake tube off to check the throttle body and saw the air intake tube had dry cracks on the bellows, I replaced it and never stalled again.

The second issue happened on my work car a Nissan Maxima. The car started missing every now and then, took it to the dealer and same shit they started throwing parts at it and could not figure it out. They wanted to change out the coils at my cost hoping to fix the problem at that point I picked up the car and started to remove the coil boots and there was the problem one coil boot had a fracture crack in it, changed it out and it’s been running great since.

The point here is do a little research get your hands dirty and you might fix the issue yourself. Good luck and keep us posted.

 

[AZCreeker]

Did you ever do a pressure test on the coolant system and on the washer system. Sometimes you have to do the testing yourself. I have run into two issues in the past that the dealer could never diagnose nor fix, all they did was throw parts at it at my cost and believe me it was very frustrating a costly. I ended up fixing those items for less than 40 bucks. Those issues were not GM related but shows you how incompetent those mechanics are.

The first issue happened on my wife’s Nissan Sentra it started stalling out, out of the blue. The dealer changed all sorts of sensors and none fixed the issue. I ended up taking the air intake tube off to check the throttle body and saw the air intake tube had dry cracks on the bellows, I replaced it and never stalled again.

The second issue happened on my work car a Nissan Maxima. The car started missing every now and then, took it to the dealer and same shit they started throwing parts at it and could not figure it out. They wanted to change out the coils at my cost hoping to fix the problem at that point I picked up the car and started to remove the coil boots and there was the problem one coil boot had a fracture crack in it, changed it out and it’s been running great since.

The point here is do a little research get your hands dirty and you might fix the issue yourself. Good luck and keep us posted.

The dealer detected the smell as well when they changed the evap canister, and concluded it was a fuel smell.
I also believe it is now, my previous assessment thinking it was a sweet smell was driven by what another independent shop was telling me.
I am now going back to the dealership who is very active about wanting to fix this for me I have to say.
They will be looking at possible leak on the injectors.
I am doing this now as we are still for another year or so I believe under powertrain warranty.
Are injectors covered by this? I have 3 TSB for them to look at, see if they were performed.
all 3 are regarding the high pressure fuel system.

What bothers me, and at this price point of a vehicle, is the downtime and inconvenience.

I am hopeful about Chevrolet finding it out this time, I just don't like getting a equinox as a loaner because "that's all we have". I might have to complain a bit and ask them to pull a traverse or tahoe or something that will suit my wife in the interim.

What a pain.

 

[ivin74]

The dealer detected the smell as well when they changed the evap canister, and concluded it was a fuel smell.
I also believe it is now, my previous assessment thinking it was a sweet smell was driven by what another independent shop was telling me.
I am now going back to the dealership who is very active about wanting to fix this for me I have to say.
They will be looking at possible leak on the injectors.
I am doing this now as we are still for another year or so I believe under powertrain warranty.
Are injectors covered by this? I have 3 TSB for them to look at, see if they were performed.
all 3 are regarding the high pressure fuel system.

What bothers me, and at this price point of a vehicle, is the downtime and inconvenience.

I am hopeful about Chevrolet finding it out this time, I just don't like getting a equinox as a loaner because "that's all we have". I might have to complain a bit and ask them to pull a traverse or tahoe or something that will suit my wife in the interim.

What a pain.

Please read this topic about fuel injectors. That's probably your case

There are TSBs for noises, buzzing and vibration concerns from bad check valves and high-pressure fuel pumps that may give off a fuel smell or actually leak

https://www.autoserviceprofessional...erns-new-technology-affects-service-practices

 

[AZCreeker]

Please read this topic about fuel injectors. That's probably your case

There are TSBs for noises, buzzing and vibration concerns from bad check valves and high-pressure fuel pumps that may give off a fuel smell or actually leak

https://www.autoserviceprofessional...erns-new-technology-affects-service-practices

Ivin74,

Thank you so very much.
This is why these forum are awesome.

Everyone,

If what Ivin74 is refering to happens to be the real issue, it will now be the second time this community will have helped me a bunch.
First time was when a member posted about the AC compressor failing along with a perfect write up and picture of letter sent to owners.
I am thankful for the quality of the info found here.

 

[AZCreeker]

bringing back this thread from the dead.
Suburban is now at 80k miles.
While I havent figured out the issue, I have now identified that the smell is clearly located at the tail pipe.
I was smelling it around the truck due to the exhaust pipe turndown to the ground, reverberating around...

As of today, my "symptoms" are:

-excessive black soot on the lower body panel on side, and everywhere throughout the back of the car.

-the strong emission smell as described above at startup, no matter old or cold startup.

-Smoke (cant tell the color) when gunning it from a start (noticed this this morning looking at headlights in my rear mirror.

I am taking the truck to a independent GM expert to see if they are able to diagnose my issue, they are going to change oil and do a chemical cleanup of the intake track related to the direct injection

Anyone having same issues?
the edible arrangement offer is still valid for the person who will correctly guess!

 

[BourbonNcigars]

I'm in no danger of winning the edible arrangement, so I'll just add absolutely nothing to this other than a free bump and say that when I do revisit buying another Tahoe, it will not be a '15.

 

[iamdub]

I'm in no danger of winning the edible arrangement, so I'll just add absolutely nothing to this other than a free bump and say that when I do revisit buying another Tahoe, it will not be a '15.

Will we soon be giving you lowering and audio advice in the "What did you do to your NBS GMT800...?" thread?

 

[BourbonNcigars]

Will we soon be giving you lowering and audio advice in the "What did you do to your NBS GMT800...?" thread?

Actually, just yesterday I was poking around Autotrader to see what pre-99's might be out there for ***** and giggles. I so badly miss my '96 two door 4WD. I wake up every morning and punch my sack for getting rid of it. Seems that finding one up to my standards in this area for a reasonable cost is doubtful. Guess most of them are just too used and old now.

 

[swathdiver]

bringing back this thread from the dead.
Suburban is now at 80k miles.
While I havent figured out the issue, I have now identified that the smell is clearly located at the tail pipe.
I was smelling it around the truck due to the exhaust pipe turndown to the ground, reverberating around...

As of today, my "symptoms" are:

-excessive black soot on the lower body panel on side, and everywhere throughout the back of the car.

-the strong emission smell as described above at startup, no matter old or cold startup.

-Smoke (cant tell the color) when gunning it from a start (noticed this this morning looking at headlights in my rear mirror.

I am taking the truck to a independent GM expert to see if they are able to diagnose my issue, they are going to change oil and do a chemical cleanup of the intake track related to the direct injection

Anyone having same issues?
the edible arrangement offer is still valid for the person who will correctly guess!

Pictures? Wonder if there's a leaky injector, works fine but drips into cylinder overnight causing unburnt fuel smell and soot. Hmm...

What kind of mileage are you getting?

 

[ivin74]

Pictures? Wonder if there's a leaky injector, works fine but drips into cylinder overnight causing unburnt fuel smell and soot. Hmm...

What kind of mileage are you getting?

I agree