Time for a DPF bake? Excessive and long rolling regens

You have an exhaust leak, fix that first. Most commonly the main exhaust bellow or flex pipe under the cab with the high mount exhaust.

Clean or replace the DPF your choice and I would throw a DPF pressure sensor on for reliability if it’s never been replaced. Engine management sensor cleaning and clean and service the Fuel doser.

All these items done properly will put her back to normal.

 

Have your DOC cleaned or replaced too. Whitish smoke during Regen (raw fuel) is indicator that fuel is not being oxidized across DOC and DPF.

 

Do everything goodysnap recomended buy also have them change your EGR valve as well. If you have been blowing smoke for a while and the valve is worn it can cause it to seize up even after being cleaned hence the smoke issue. I would also guess your system is contaminated so i would have any sensor in or along the exhaust line pulled and cleaned as well as your EGR pipe pulled and cleaned. Also have them check the turbo just to be safe an ensure there are no major buildups of soot that could destroy it.

 

Yes and the sooner the better ! I didn't know mine was leaking until it melted the air lines going into my transmission.

 

what would it mean if there is a blueish color smoke that comes out for a couple seconds while the truck is regening going down the highway?

 

Blueish/white is usually raw fuel that didn't react with the DOC and DPF.

 

Whats the average lifespan of a DPF pressure sensor? Or at what mileage are they recommended to be changed out at?

 

Nothing concrete really. Most line haul trucks I would say start acting up around 500k. Vocational maybe 200k. I can tell you that I replace a lot. They can really be tricky to pick out even for a well trained eye. The regen history will tell a story. Drastic changes in the pressure reading from one regen to another in the history is a telltale for sure. The DPF pressure should be a gradual increase. Not sudden changes in pressure from 1 regen to the next.

The sensor can become biased pressure but still function in range and cause random frequent regenerations even though the pressure is really normal.

Many times I have seen DPFs cleaned and or replaced only to end up replacing a bum sensor for frequent regens.