[CulmerBuilt]

Hello all. First post here. It’s been a useful place for info so far. Here’s my situation. 2020 Z71 sbcc. Threw a fuel code with about 5000mi on it. Code cleared itself, dealer said my fuel might have gelled, because the light came on at 32*. Fast forward now at 9000mi. Start truck one morning, it idled rough for a minute, then died. Repeated this 5 times that morning. Take it in, they don’t know what went wrong, referred it to engineering, they don’t know what happened either. So they are replacing the HPFP, fuel regulator, fuel rail, and filters, even though it’s currently running just fine. From now on I will be using a diesel additive, but I’m just curious what the issue is here. I bought this thing over a Tacoma believing it would be reliable and last me 15yrs. My confidence isn’t so high anymore. Curious to hear theories. Thanks.

 

[CleverUserName]

HPFP failures are usually caused by fuel contamination. Usually water or if somebody accidentally put gasoline in the tank at fill-up. Biodiesel > 20% could also cause damage.

They should also be draining your tank and/or testing the fuel to ensure it's not due to contamination.

Overall these new Denso CR diesels are much better than the previous Bosch units, mechanical failures are uncommon.

 

[CulmerBuilt]

I bought it new, never put gas or bio diesel in it, and the filter should separate water out, correct?

 

[CleverUserName]

I bought it new, never put gas or bio diesel in it, and the filter should separate water out, correct?

I assumed you bought it new. Yes the filter is designed to separate water. Biodiesel is hygroscopic which means it holds water and can absorb it from the air.

You may have not intentionally put any other fuel in it, however if you let a friend, family or spouse drive the vehicle they could have. It's also possible the fuel could be contaminated at the station itself. It's best to save fuel reciepts just in case.

For example, it is common practice with VW to test the diesel fuel if a TDI HPFP goes bad. In fact, I helped a guy out with a 2012 Passat TDI that had a HPFP failure and VW denied warranty coverage because of fuel contamination, but VW would not provide any specifics why. He was on the forum asking for help because he did not know what to do and was being victimized by VW. I instructed him to send in a sample of fuel and it was determined to be B10 which is above the B5 rating for that generation of TDI. Every other constituent in the fuel was acceptable except the % of biodiesel was above the maximum allowed by VW. To make matters worse, he was in illinois which has a biodiesel mandate, but does not have any labeling requirement. So it is almost impossible to know if the fuel your getting is B5, B10 or B20.

He got a lemon law attorney and VW fixed his car. It was almost $10K repair which is why VW didn't want to pay for it. I do not know the specifics about GM or how they will handle it but I'm just providing some information to help you out.

Good luck.

 

[Burgess159]

Make sure you use a good additive too. Stanadyne, Amsoil, John Deere or Opti-Lube products are all top notch.

 

[RollyPollieBenito]

Sound just like what happened to my canyon when I was in Yellowstone. I dumped a small bottle of power service antigel and it sorted itself out after about 30 minutes of rough idles and stalling.

 

[CulmerBuilt]

Sound just like what happened to my canyon when I was in Yellowstone. I dumped a small bottle of power service antigel and it sorted itself out after about 30 minutes of rough idles and stalling.

Weird. Mine happen at 46*. Acted normal since. Chevy is stumped and are just throwing a ton of parts at it. So in a way I’m glad to hear it didn’t leave you stranded, but always gonna wonder now when I’m camping a hour out a dirt road.

 

[RollyPollieBenito]

Weird. Mine happen at 46*. Acted normal since. Chevy is stumped and are just throwing a ton of parts at it. So in a way I’m glad to hear it didn’t leave you stranded, but always gonna wonder now when I’m camping a hour out a dirt road.

My truck is just like everyone else. It have its issues. The one thing to remember is diesel power in itself require different attentions. I am fortunate enough to have a friend that deal with large earth moving machines and smaller diesel vehicles. Apparently what our little diesel experience is nothing new or different than those other diesel. When I have a question or issue, I run it by him would share his knowledge or get answers from his team of diesel mechanics.
my truck is over 37K miles and only about 3K or less is driven around my town. my longest daily single trip distance is 1.5 mile. I have been told on this forum that short distances is bad for the diesel. 10 months out of a year and 7 days a week since April 2017, I have a max of 3 miles a day. The other 34K miles is from a handful of camping, overlanding and visits to Canada and Mexico (2 months out of a year). I’m not afraid of it breaking down. Heck the Tundra That this truck replaced had more issues.
My advice to you is, find a diesel repair shop and get your oil change there and befriend the mechanics and pick their minds. You can learn a lot.
Beside catch can, 2” lift and 32.4” tires, my truck is completely stock.

 

[CulmerBuilt]

My truck is just like everyone else. It have its issues. The one thing to remember is diesel power in itself require different attentions. I am fortunate enough to have a friend that deal with large earth moving machines and smaller diesel vehicles. Apparently what our little diesel experience is nothing new or different than those other diesel. When I have a question or issue, I run it by him would share his knowledge or get answers from his team of diesel mechanics.
my truck is over 37K miles and only about 2K or less is driven around my town. my longest daily distance is 1.5 mile. I have been told on this forum that short distances is bad for the diesel. 10 months out of a year and 7 days a week since April 2017, I have a max of 3 miles a day. The other 35K miles is from a handful of camping, overlanding and visits to Canada and Mexico (2 months out of a year). I’m not afraid of it breaking down. Heck the Tundra That this truck replaced had more issues.
My advice to you is, find a diesel repair shop and get your oil change there and befriend the mechanics and pick their minds. You can learn a lot.
Beside catch can, 2” lift and 32.4” tires, my truck is completely stock.

Nice. Ok, I was thinking the same about finding a diesel shop, I hope it’s just learning the nuances of a diesel like you said and then my trust in it can repair itself. Do you use a fuel additive?

 

[RollyPollieBenito]

Yes, 2 bottles of Power service live in the bed of my truck, when I get into colder weather and I expect the temp to drop, I dump half a bottle in with my fill up. 2 bottles last me 4 full tanks.

 

[RollyPollieBenito]

When I had my issue at Yellowstone, I used Power Service 911. The bottles that live in my truck is power service supplement + cetane.

 

[CulmerBuilt]

When I had my issue at Yellowstone, I used Power Service 911. The bottles that live in my truck is power service supplement + cetane.

Every time you fill up?

 

[RollyPollieBenito]

Every time you fill up?

I only use the supplements when I am in cold weather, anything below 40F. And it is overkill, but every tank while in cold weather.

 

[RollyPollieBenito]

Not very scientific, but the way I do it is, I google the weather of the route that i am taking. That is how I determine when to add power service.

 

[CulmerBuilt]

Not very scientific, but the way I do it is, I google the weather of the route that i am taking. That is how I determine when to add power service.

I’m in California. It’s not a cold weather issue for me, but I’m wondering if there’s a benefit to using it anyway, adding Cetane?

 

[RollyPollieBenito]

I do not know if there is any benefit. I don’t use it when I’m home in SoCal. The only time I use it is when I head north.
Also I forgot to say, I only use power service because it was the only brand I found in West Yellowstone. And my buddy get them for me at contractor’s price. I heard of other brands from people on this forum that are suppose to be better. So look around for other brands.

 

[Streamintrip]

I’m in California. It’s not a cold weather issue for me, but I’m wondering if there’s a benefit to using it anyway, adding Cetane?

For me it is 20 oz Diesel Kieen (gray bottle) every fill up. Cetane booster and more lubricity. Power Service anti-gel (white bottle) for those low temps. Both protect from problematic fuel that you're bound to pump without knowing it!

 

[CulmerBuilt]

20

For me it is 20 oz Diesel Kieen (gray bottle) every fill up. Cetane booster and more lubricity. Power Service anti-gel (white bottle) for those low temps. Both protect from problematic fuel that you're bound to pump without knowing it!

20oz for every tank? Wow that seems like a lot, I figured it would be about 2-4oz of stanadyne per tank. Maybe I’m way off. Anyone else using additive every tank?

 

[Burgess159]

Wce

20

20oz for every tank? Wow that seems like a lot, I figured it would be about 2-4oz of stanadyne per tank. Maybe I’m way off. Anyone else using additive every tank?

Every product is different. Amsoil is like 1-2 oz. per 5 gallon. So, 8 oz. per 20 (since you probably have a few gallons left when you fill up). I believe Power Services and Howe’s (don’t use Howe’s whatever you do) have higher use rates though.

 

[RollyPollieBenito]

For me it is 20 oz Diesel Kieen (gray bottle) every fill up. Cetane booster and more lubricity. Power Service anti-gel (white bottle) for those low temps. Both protect from problematic fuel that you're bound to pump without knowing it!

can I ask why you put 20oz in a 20 gallon tank? The 32oz bottle treat 100 gallon.I’m looking to use it.