6.4 hot coolant

[Jake6.4dunlap]

Hi,
So today I was in my truck and I noticed that my mini maxx tuner was saying that the coolant was getting hot and that it was setting my truck to the stock tune. The coolant temp will increase up to 222* when I'm sitting still then when I drive it will lower back down to about 199* but every time I take my foot off the pedal and coast the coolant temp will rise again? There are no engine lights that come on the dash only on the tuner and the coolant guage does not look any different than normal it stays about half way?

Any ideas on what my problem may be?

Thermostat or sensor is what I was thinking?

 

[Rubenk]

Sounds like fan isnt kicking in. Whats the delta between oil and coolant temps?

 

[Jake6.4dunlap]

The deltas very when the coolant is lower like around 200 it's about an 11* difference between that and the oil temp. Oil temp being hotter. But when the coolant temp is up around about 220* it's about a 1-2* difference.

 

[White_monster]

Sounds like a water pump. As you accelerate you spin the water pump faster and when you coast the pump isn't turning fast enough. Maybe the impeller is slipping on the pump shaft.

 

[forcefed6.4ford]

Im inclined to agree with yoda.