Believe, me, this is not intended to insult you, but by your avatar, you must have some knowledge of engines? Have you looked to see if there is a sensor on the manifold?
'05 Monaco Beaver 400 Quad SLD 400hp C-9 Caterpillar
2014 Grand Cherokee, Limited, diesel
Katie-Doberman Pinscher, Tigger, yellow Tabbycat.