2007 Hino 268 power loss / 35 mph max

[Davenpbl]

Morning,

I have a 2007 Hino that has an issue I can't figure out. We've replaced the fuel filters, and the brake switch sensor in the back near the wheels.

Here's a video showing what the truck is doing

Hino power issue.mp4

drive.google.com

Thanks for any thoughts...

 

[GreaseMonkeyTX]

On mine there are two brake switch sensors and I had replace both of them for the issue to go away

 

[Davenpbl]

thanks, the one pictured was replaced...though you're saying there are two. Don't think we did both of them.

 

[GreaseMonkeyTX]

If you are umder the truck by the rear wheels facing the front,onei s on your immediate right and the other one is almost in the middle of the axle...you cant miss them...change both or switch them around to test for faultiness

 

[GreaseMonkeyTX]

Hoping that you checked all the fuses and that the brake swich behind the brake pedal has also been checked..

 

[greasytshirt]

There's a couple air switches under the truck, but only one is a brake switch. The other brake switch is in front of the brake pedal. The inputs of these brake switches both have to correlate.

 

[Davenpbl]

so we ended up taking it to the shop... as of Friday they think its an EGR valve issue (though still T/S)

 

[greasytshirt]

Sometimes the 2005-2007 trucks develop EGR problems that you can see with software (the valve can't be commanded through its full range of travel) yet it won't set a CEL. The symptoms for that tend to be terrible acceleration off the line but seemingly normal power at higher rpms. Since it's at the shop, they should check for brake switch/stop light switch correlation at all times.