Hot Exhaust Light after exiting freeway and smoke

Regenning or trying to, you just exited in the middle of it. If it starts throwing codes then be worried, but its not a big deal for the light to come on and smoke pour out.

 

Was a regen occuring at that time? Not sure about trucks but construction equipment need to display a high exhaust temperature warning light during regen to notify the operator that a regen is in progress.

 

My Maxxforce use to smoke when sitting still doing a regen. It ended up being a broken mesh/flex pipe between the manifold and the DPF. On a Cornbinder, it was $800+ for just the part.

 

Like others said truck was doing active Regen going down the road. Getting off the highway stopped the Regen and the computers are telling you the exhaust temp is very HOT and Don't park in dry grass or something flammable.

The exhaust temp is probably pushing 800-1,000 F. I would idle truck to keep air going thru exhaust to cool it down a little bit, that just me. They don't say cooling it down is required.

 

A "hot exhaust light"? Oh, please, isn't that what pyrometers were for?A good driver knew when she was getting hot. I'm not rippin' on the OP, just where trucking has gone in general,,,hot exhaust light,,,

 

Most modern trucks don't have pyrometers any more...and if they did, it's up near the manifold. Today's trucks with a DPF have hotter exhaust coming out of the DPF during a regen than older trucks had coming out of the engine. So when one is doing a regen, it tells you by lighting up a light...otherwise, you couldn't tell when it's doing what it's suppose to. Times have changed with equipment

 

There should be no exhaust leaking from the DPF, it can cause it to improperly complete it's regen process. If it never regens properly it will cause more problems sooner rather than later. Even small exhaust leaks now need to be addressed. At the next PM should be fine. Just don't keep putting it off. Also have a look at the doser injector, it will cake up with soot over time. It needs to be cleaned or replaced so your DPF has a longer service life.

The HEST light comes on if you happened to slow to <5 mph while it was in the middle of a regen cycle while going down the road. There generally isn't anything it will show while you are driving, you won't even notice it most of the time.

Pyro gauge will show what exhaust temp is right at the turbo hot side or thereabouts, HEST just says DPF is very hot. 1600 F or so IIRC. So, if you need rid of the truck and would like to make good use of your fire insurance policy, you could park it on top of some dry grass or other flammable material, and hope for the best.

 

The best place to park when doing a forced regen is at the fuel pump under that canopy that keeps us out of the weather, surprised there is not more fires around with the high heat coming out of those stacks.

 

This regen business is he work of the devil.

I hate to be difficult. We did not have a problem in the old days and now we do.