Here’s What GM Recommends If Diesel Exhaust Fluid Was Added To The Fuel System16
Refuelling and tending to a diesel engine can cause confusion among uninformed or inexperienced users. In addition to accidentally refilling the fuel tank with gasoline instead of diesel, some motorists may mistakenly put the Diesel Exhaust Fluid (DEF) into the fuel tank, which can affect the performance of the fuel pump module, or lead to more serious problems.
On its Techlink service site, GM has outlined steps to follow for diesel car or truck drivers that mistakenly add DEF into their vehicle’s fuel tank. The first thing to know is that if diesel fuel is mixed with DEF, or if DEF or gasoline is added to the fuel tank, it may lead to repairs that will not be covered by GM’s factory New Vehicle Limited Warranty.
Major repairs can be avoided if the ignition is not turned on, the engine is not started and the vehicle is not driven. In scenarios where the in-tank fuel pump has not been run, the fuel fill pipe, tank and fuel pump module should be replaced. If the fuel pump has been run but the engine has not been cranked, the system from the fuel fill pipe to the high-pressure fuel pump, as well as the high-pressure pipe from the pump to the rail, must be replaced along with the low-pressure return lines.
In scenarios where the engine has been cranked, the entire fuel system from the fuel fill pipe to the high-pressure fuel pump, fuel rail, injectors, injector return fuel lines, high-pressure fuel pipes and low-pressure return lines must be replaced. A fuel pump module that has been contaminated with DEF may show corrosion of certain steel and aluminum components, a crystal-like residue on the module’s exterior or fractured/damaged terminals.
GM also notes that if DEF was added to the fuel tank, the vehicle should not be driven to the dealership for service. Additionally, the vehicle ignition should not be turned on and the vehicle should not be started.
“These actions will help limit any damage to the fuel system from contaminated fuel,” the automaker says. “The New Vehicle Limited Warranty may not cover any fuel system repairs related to fuel contamination.”
Some GM models that are available with diesel engines and may experience DEF contamination include the GMC Savana and Chevrolet Express utility vans, GMC Sierra and Chevy Silverado full-size trucks and its line of full-size SUVs like the GMC Yukon and Yukon XL and Chevy Tahoe and Suburban.
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Based on your comments on a daily basis, you’re describing yourself.
This is what happens when people who think they know better complain loudly about the DEF filler being under the hood.
Actually, it still happens when the DEF filler is under the hood. A fleet employee sees the message about adding DEF and thinks its a fuel additive and adds it to the fuel.
I’ve had this happen to several commercial customers.
Costs over 10 grand to fix!
I saw this several times while at the dealership. Grown men. Just a mistake, no one did it on purpose. I recommend calling your insurance company.
Isn’t it amazing how much stuff GM wants you to replace when its not covered under warranty.
If the fluid had just been called PEE (for powetrain emission enhancement) this situation probably wouldn’t exist, but would have resulted in a different problem based on misconception.
Simple fix.. get rid of DEF.
EPA crap mandate that retards fuel mileage and ultimately is worse for the consumer and environment as it requires you to use more fuel and pay more for the fuel and fuel emissions equipment that is added on to the vehicle that oh so frequently craps out.
And if you use more fuel, are you really saving the environment?
There’s always at least one idiot who comes in here and spews out some crap without knowing what they are talking about.
DEF actually improves fuel economy while also reducing harmful emissions. Win-win.
Clearly you have never deleted a diesel or know someone who has.
Drive a Prius?
Look in the mirror for the idiot.
Modern engines create more NOx than before due to lean burn and reduced EGR. Closed-loop DEF control, introduced in GHG17 engines, destroys this NOx very effectively. European diesels don’t even use EGR. The impact of SCR on fuel economy is actually positive.
You’re confusing DEF/SCR with DPF.
Idiots with Rolling Coal !
Another reason why I didn’t get a diesel. I figured I’d be that guy that fills the tank with gasoline by mistake. DEF gives me a second chance to screw it up.
Having worked at GM dealerships for almost 35 years, and having repaired many Duramaxs, we never replaced all the components listed, especially for gasoline added to the tank. Flush the tank out, replace the fuel filter, and add new diesel fuel to the tank. This is even after they drove it to the shop.
Why? No one would pay thousands to replace all those “required” parts and pay the labor for it. Saw no long term issues either. Engine runs a little rough until gasoline is cleared out. That’s it.
Shoddy dealership work strikes again!
What you don’t know is that the DEF will cause severe corrosion of the fuel system. Any corrosion of the fuel system eventually ends up in the exhaust and trapped by the DPF. Because it’s metal and not carbon, it won’t burn off during a regen and permanently plug it.
So, the net result is that fuel economy is permanently decreased, regens will be more frequent, and eventually you’ll get a code to replace the DPF before the ~200k lifetime.
If only DEF was in the fuel system, corrosion would be likely. But if a couple gallons of DEF was added to a full tank of fuel, the damage would probably not occur. Also if a dealer employee did this, at the dealership, there is no way the entire system would be replace! It would be flushed, and done a cheaply as possible!
Just get rid of the DEF the truck will run better and get way better fuel mileage.