EBPV Closing While Towing?

[Blk03PSD]

On several occasions while towing my TT I have encountered a situation where the engine, while under load and rolling down the highway at 60 - 65 suddenly sounds like it is idling higher like when you start up in the morning. I litterally getting two engine sounds in two different levels. I do not experience a loss of power, it just sounds like the choke is on or a big electric cooling fan is on under the hood, over the regular engine noise? I know it doesn't make any sense but it has happened a couple time and it is very disconcerting.

Any thoughts?

 

[94f450sd]

its most likely the fan clutch locking up so the fan will cool the engine.the ebpv should not be comeing on at that speed.

 

[Blk03PSD]

That makes perfect sense because that is exactly what it sounds like. I have just never experienced the fan engaging at highway speeds. I will watch the engine temperature nect time I notice it.

Thanks, Rich.

 

[94f450sd]

fords are known for haveing a seriously loud cooling fan.kinda sounds like a rocket launching when it engages

 

[CHPMustang]

I think the highest speed our EBPV closed was about 35 mph but it was in the teens.