I just towed my 5000lb trailer from Maryland to Florida. About 300 miles into my trip the check engine light came on. Seeing as I was too far into the trip to turn around, I keep pressing on. When I got to Florida and unhooked the trailer, the check engine light went out! What gives?

Drove down the whole way with OD on...


My buddy seems to think that the tranny might of been over heated and that caused the check engine light.


Questions? ANswers?

Thanks

Big Mick

 

Here are my best guesses from experience. If your tranny had overheated, the Overdrive light on the shift stalk would have started flashing, and eventually the tranny would have gone into emergency mode, with higher shift points, and very rapid, hard shifts. It apparently didn't, but I would follow the owners manual from now on and tow that kind of weight without overdrive. The difference in gas mileage is neglible, and by keeping the engine higher in revs, you get more of the torque and HP you need for towing. Your Triton engine loves revs. It'll go all day long at 4500rpm without a strain or wear.

Since the engine check light was on, I'd guess that you bought some bad gas, diluted wth too much oygenator or alcohol. One tank of that, and it will take another tank of so before it corrects itself and turns off the light. I've had this happen several times, and know exactly which brand gas stations I got that bad gas. I dont' buy there anymore.

Second, the extended high temps in the exhaust on a longer than usual trip could have confused one or more of the O2 sensors (there are four of them) as they collected carbon residues from low mileage around town trips burned off the valves, headers, pipes and cats. This junk can cause temporary bad signals, and disappears with contraction when the system cools off, then is started again.

 

Thanks for your input.... I'm going to AutoZone to have it checked out.

Thanks


Big Mick