this may sound like BS

[02screw]

I installed my chip a few weeks ago and it is great. Today I decided to pull a camper weighing about 3 k.. I put the chip in stock mode because I have not put in my pyro yet. It now seems that my truck will overheat in the stock setting but not in any other one.. it does not matter if I have the trailer or not. Does this sound like anything anyone has heard of before..

[907DAVE]

Overheat, as in coolant temps?

[02screw]

Yes, and I would call BS if I had not seen it myself

[cleatus12r]

What are you looking at when judging coolant temperature? The PCM is not responsible for any coolant temperature gauge control and on an automatic transmission truck (assuming that's what you have), there isn't any coolant temperature input to the PCM anyway.


If you're looking at the gauge in the dash, it's controlled by a sending unit (not a switch), but I would still put very little faith in what it reads.

[02screw]

The gauge in the dash was reading HOT in the red. I know the chip does not control any of the cooling system but I was wondering if it was possible that just maybe the position that is supposed to be stock could have some weird tune that is causing a fuel air mixture that will overheat an engine. It will only get hot if I have the chip in the stock position. It is very strange.

[cleatus12r]

Without getting into the mechanics of how a diesel engine actually works, I can tell you that there's nothing wrong with the air/fuel ratio. I'm not trying to tell you that there's no way the tuning can be screwed up, but only overly "rich" air/fuel ratios cause high combustion temperatures in a diesel. If the stock tune doesn't smoke like a pile of burning tires and the RPM is completely controllable with your right foot, then there is nothing going on in that tune that is causing your issue.

[02screw]

Okay thanks for your reply. I will post when I figure out the problem.