Ambulance Aero

[JSH]

Originally Posted by Drifter

Congratulations - sounds like it has been an adventure so far.

Have you pulled the DPF to inspect & clean it? I'd normally expect to go around 1,000 miles between (rolling) regens on a cross country highway trip - every few hundred miles is a bit of a red flag. Hopefully the thermostat & DEF heater were the problem, but fire trucks & ambulances tend to idle a lot so it isn't unusual for them to start needing DPF replacements as early as 50,000 miles. Still, your engine has pretty low hours for the miles so it definitely didn't idled all the time...

No I haven't pulled the DPF to inspect it. I did spend a day tracing wiring and pulling out a battery cut-off switch that installed poorly and didn't work. In the process I found the battery terminals were loose on the front battery under the hood. I was hoping that might we a source of my problems - ECU's had poor grounds but it was not to be.

It is not fixed - DFP cleaning message and check engine light came on 500 miles from Denver like clockwork. I made it 200 miles before it hit limp mode just before I got to the Chevy dealer. This time I had to call 5 dealers along my route before one would get me in the same day. The dealer did a forced regen and we got back on the road. 500 miles later the check engine was back on just like clockwork.

With 110K miles on the truck I expected to have to change the DPF. However, I want to make sure that is the actual issue. I don't want to swap it out and then plug up a new DPF. What concerns me is that the truck doesn't even seem to try to do a regen. I get the Exhaust Filter Cleaning message and then 3 minutes later it gives up. There is no way that was a complete regen attempt so something is causing the regen to abort. However, the dealer forced regen works so a regen is possible.

[cRiPpLe_rOoStEr]

Originally Posted by JSH

I would likely do an air deflector on the top of the cab (factory option so easier to find / install than some custom fabrication)

[JSH]

Quick update since this thread got bumped.

I took it to my local dealer and they said the 9th injector wasn't working so they replaced it. (9th injector is in the exhaust and sprays diesel into the DPF during regen) I'm crossing my fingers that that was the final repair.

I drove it to work one day and averaged 16.5 mpg according to the computer.

Besides that I haven't done a whole lot. The interior is almost completely stripped and I've started tackling the wiring. I would not be surprised if this vehicle has 10 miles of electrical wire.

I should take some pictures and start a build thread.

[JSH]

Minor update. The emission system is fixed. I've done 750 miles since the 9th injector was replaced and the truck has regenned twice. I drive it to work and back about every 2 weeks to keep it moving.

I have averaged 15.4 mpg commuting and it is by far the best commuting vehicle I have. Again the magic of an ambulance - when you put on the blinker a gap just opens up in traffic.

[cRiPpLe_rOoStEr]

A friend who owns a Citroën campervan also had trouble with a DEF injector during a recent trip to Chile.