I have a 2008 6.4 that is DPF deleted and tuned with an H&S Mini Maxx. The truck has been deleted since ~2010 and did not trigger the check engine light for ~10 years.

For some reason the CEL is now showing up with codes such as P2452, P242A, P2031, P0544 which all appear to be codes associated with the exhaust system, that I would think should be ignored or “silenced” by the tuner.

I am running a no-bungs delete pipe, with the exhaust sensors still plugged in, but zip tied up to the frame and out of the way.

Any ideas why the CEL would now be triggering? The truck seems to be running fine as usual.

 

I did the same thing with my delete. If memory serves, the three EGT sensors that you have non bunged and tied to the frame should be fine, just check the connections to insure one didn't get compromised. There is also one more that's upstream that is on an up pipe near the top of the engine behind the head. Passenger side I believe.

Denny

 

https://www.thedieselstop.com/thread...ations.296289/

May help

Denny

 

There are 4 EGT sensors:
1 in the passenger side up-pipe which is still installed and used to report EGT on the mini maxx

3 downstream in main exhaust piping. All of which are zip tied out of the way, still plugged in and not compromised

additionally there is a exhaust back pressure sensor that is capped off but still plugged in.

 

I just did a quick search on those codes and all of them seem to be a circuit problem. Look for a connector issue someplace. Unplug one of the sensors and see if you have proper voltage to them. If not then look for damaged wiring or connector. Can you get a diagnostic scanner and read the values of the sensors? If so then see what they are.

 

The mostly likely scenario is a wring fault, perhaps a chaffed wire or other fault in one of those zip tied up sensors unless you took the truck to a dealer recently for anything. Even taking a truck to a dealer to get new tires put on will result in them running the VIN and performing any Ford recommended software updates (without customer knowledge or consent BTW).
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