Escalade dies after driving a while and comes to a stop

[escalade 3rd gen]

It had to be running for a long time and then it will start shaking a lot then die unless I rev it up in neutral for a little bit. The first time it happened I was just sitting in a Walmart parking lot with the air on. It dies faster the more it's been driven aggressively. It starts up again after a few minutes. Today the trans temp went all the way to 201F and it usually stays at 135-175. One mechanic said that its getting stuck in 3rd gear and causes the engine to stall but idk how that would work because it still happens even in park. Another mechanic thinks its the fuel pump or spark plugs but the fuel pump is new. I still have to see about the spark plugs. ive also been getting about 7.5 mpg and there is 207000 miles on this 2007 caddilac escalade. After I get off the highway or ive been going above 40 mph for a while thats when it starts shaking a whole lot and the rpms start dropping to about 250 rpm and then it usually dies unless I rev it in neutral. Today I went to the highway and went straight to the mechanic and it was like the engine couldnt wait to move like it was moving a lot quicker even without me pressing the pedal. Usually when its trying to go dead you can see smoke or gas coming out the engine next to the oil but this time there was none. I just got the vacuum leak fixed today and its still trying to go dead. It hasnt actually gone dead today even though it was really trying to like it was reving itself up without me pressing the gas pedal. at 35-40 mph you can hear a really deep sound like a viberation or a helicopter kind of sound or 20hz. You can only hear it if you press the gas pedal. On the highway its like the whole cars shaking and one wheel is getting a lot more power than the others. Its not bad at 70mph but when you start speeding up to 106 its really bad. (I usually go 80mph). I have to drive it like an old grandma in a caravan for it to act normal ( until I start going past 40mph). It also feels like its not downshifting right like when you press the gas about half way it usually drops a gear and starts speeding up really fast but now Idk if it does that or not. Ill test that later. When you scan it at autozone or orileys the only thing that comes up on the check engine light is the EVAP and thats it. I used to be able to smell something burning when I floored it when this first started happening in april but now I cant smell nothing at all. It has had 2 crankshaft sensors and a camshaft sensor.

 

[petethepug]

Lucky you! 07 Esky and no AFM on the 6.2L. If you can, determine the build date on it to confirm it’s not one of the very few equipped with sleeping AFM.

https://static.nhtsa.gov/odi/tsbs/2020/MC-10180695-9999.pdf

Two things to start with:

a) Replaceme the -\~ battery cables. They rot from the inside out, look perfectly normal and cause bogus DTC to appear on the 5v CAN/BUS system.

b) Ever changed the carbon canister back by the gas tank? The pellets get in the gas tank, evap lines & fuel lines.

If the canister is leaking carbon pellets, there’s a systematic process of replacing the inexpensive evap/emission parts, replacing the fuel pump w/ an OEM lifetime unit, wiping out the tank and blowing out all the lines. It’s all gotta be done in one shot to rid the pellets.

All those parts should of been replaced at 100k mi anyway.

 

[escalade 3rd gen]

When we got it from the dealership it already had over 100k miles. All the electronic stuff still works when the engine turns off. Idk if the carbon canister has ever been done but would sea foam fix it? I can't smell the weired burning smell when I floor it anymore

 

[Doubeleive]

It had to be running for a long time and then it will start shaking a lot then die unless I rev it up in neutral for a little bit. The first time it happened I was just sitting in a Walmart parking lot with the air on. It dies faster the more it's been driven aggressively. It starts up again after a few minutes. Today the trans temp went all the way to 201F and it usually stays at 135-175. One mechanic said that its getting stuck in 3rd gear and causes the engine to stall but idk how that would work because it still happens even in park. Another mechanic thinks its the fuel pump or spark plugs but the fuel pump is new. I still have to see about the spark plugs. ive also been getting about 7.5 mpg and there is 207000 miles on this 2007 caddilac escalade. After I get off the highway or ive been going above 40 mph for a while thats when it starts shaking a whole lot and the rpms start dropping to about 250 rpm and then it usually dies unless I rev it in neutral. Today I went to the highway and went straight to the mechanic and it was like the engine couldnt wait to move like it was moving a lot quicker even without me pressing the pedal. Usually when its trying to go dead you can see smoke or gas coming out the engine next to the oil but this time there was none. I just got the vacuum leak fixed today and its still trying to go dead. It hasnt actually gone dead today even though it was really trying to like it was reving itself up without me pressing the gas pedal. at 35-40 mph you can hear a really deep sound like a viberation or a helicopter kind of sound or 20hz. You can only hear it if you press the gas pedal. On the highway its like the whole cars shaking and one wheel is getting a lot more power than the others. Its not bad at 70mph but when you start speeding up to 106 its really bad. (I usually go 80mph). I have to drive it like an old grandma in a caravan for it to act normal ( until I start going past 40mph). It also feels like its not downshifting right like when you press the gas about half way it usually drops a gear and starts speeding up really fast but now Idk if it does that or not. Ill test that later. When you scan it at autozone or orileys the only thing that comes up on the check engine light is the EVAP and thats it. I used to be able to smell something burning when I floored it when this first started happening in april but now I cant smell nothing at all. It has had 2 crankshaft sensors and a camshaft sensor.

just because the fuel pump is new doesn't mean anything, check fuel pressure a basic tester is only $25-30 at any auto parts or harbor freight

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

You are already receiving sage advice from the knowledgeable folks on this Forum.

 

[escalade 3rd gen]

What do u want a picture of

 

[escalade 3rd gen]

just because the fuel pump is new doesn't mean anything, check fuel pressure a basic tester is only $25-30 at any auto parts or harbor freight

How do I use it

 

[Doubeleive]

How do I use it

there is a schrader valve connector on the passenger side fuel rail (remove the plastic engine beauty cover and you will see it, should have a black plastic cap on it like a tire valve), you can connect it (like a screw on air hose) and then kinda prop it up under the hood facing the window, pressure should be 50-55 or better key-on, engine-off. then after you start it a few seconds later it should drop to around 43-44 and hang around there while driving.
if you do this while the engine is hot you may see much higher psi with key off/engine off due to heat soak.
** put a rag around and/or wear glasses so gas doesn't spray all over and in your face

 

[Fless]

Also NNBSes should have a PID to display regulated fuel pressure. That could be monitored in-cab with a scanner that displays the PID. Although that would be dependent on the accuracy of the sensor, it might just show enough to lead you to the cause.

 

[escalade 3rd gen]

there is a schrader valve connector on the passenger side fuel rail (remove the plastic engine beauty cover and you will see it, should have a black plastic cap on it like a tire valve), you can connect it (like a screw on air hose) and then kinda prop it up under the hood facing the window, pressure should be 50-55 or better key-on, engine-off. then after you start it a few seconds later it should drop to around 43-44 and hang around there while driving.
if you do this while the engine is hot you may see much higher psi with key off/engine off due to heat soak.
** put a rag around and/or wear glasses so gas doesn't spray all over and in your face

My mechanic did this and it was around that but it wasnt trying to go dead. Is there one that's really really long so I can see it while driving