[KMJake]

So I own two 06 cummins, my wife’s truck is the only one that does this so far.

When it’s cold outside in the mornings the truck starts just fine, but when it’s driving at 65, 70 the grid heater light comes on and chimes. I’ve read a couple forums and they all revert back to a smarty tune however her truck does NOT have a smarty tuner. When we bought the truck it had a bully dog gt tuner that I swiftly took off and (since I work at a dodge dealership) reflashed the pcm back to its stock configuration.

When the light kicks on, it does chime a few times but if I drop speed below 60 the light turns off and only turns on again when I hit 65+.
Anyone have any ideas?

 

[nosympathy]

Injectors. Need to do a return flow test. Rarely could be leaking tubes, almost always is injectors going bad.

 

[GRUNT 11B]

The system is detecting a high fuel return rate. There is a good chance it's an injector/injectors. You can try running a heavy dose of cleaner and lubricant do see if it fixes the problems.

Have you checked for any codes?
How many miles are on the injectors?
It's not uncommon for injectors to start failing around 180k miles, but they also can last over 300k miles.

 

[KMJake]

The system is detecting a high fuel return rate. There is a good chance it's an injector/injectors. You can try running a heavy dose of cleaner and lubricant do see if it fixes the problems.

Have you checked for any codes?
How many miles are on the injectors?
It's not uncommon for injectors to start failing around 180k miles, but they also can last over 300k miles.

I do have an intermittent fuel delivery code, the computer clears itself after a few drive cycles due to it being intermittent. The injectors have not been changed to my knowledge, the mileage on the truck is 248850. So I can see the injectors starting to fail.

 

[GRUNT 11B]

Search that code on here and you can find possible causes to the issue. If there is almost 249k miles on the injectors, there is a good chance that is the problem. You won't know without having them tested. But having them tested might be a waste of money that could go towards new injectors.

 

[RomeoOne]

It’s almost guaranteed to be worn out injectors at that mileage. Did mine last year, welcome to the club.

You can go through all the diagnostics and all that fun stuff if you wish. Me personally I think on a higher mileage rig is totally a waste of time, just change them and be done.

it’s a monitor test the engine does and it only occurs when the engine is motoring which means essentially cruising without fuel input. If yours is doing it just driving around it’s probably really bad. Mine only did it coming downhill after pulling a big grade and off the throttle while towing. Wait to start light comes on, and will will chime 10 times or something like that.

 

[KMJake]

It’s almost guaranteed to be worn out injectors at that mileage. Did mine last year, welcome to the club.

You can go through all the diagnostics and all that fun stuff if you wish. Me personally I think on a higher mileage rig is totally a waste of time, just change them and be done.

it’s a monitor test the engine does and it only occurs when the engine is motoring which means essentially cruising without fuel input. If yours is doing it just driving around it’s probably really bad. Mine only did it coming downhill after pulling a big grade and off the throttle while towing. Wait to start light comes on, and will will chime 10 times or something like that.

Yeah, I just put injectors in my truck 3 months ago. Guessing it’s her turn now.

 

[jballou]

And to add to this, the Smarty isn't the direct cause of all of the problems. It is merely the messenger for factory ECM updates. And then they modify the tuning. When you updated it after removing the BD, it flashed the latest update. And the information to calculate the excessive fuel return.