What causes high Fuel Rail temp?

[drservo]

Pulling 10k on 8% grades on the 210 perfomance tune and the 275TCM all is well except fuel rail temp. It hits 140-145 easily when pulling the grade. BTW I got 10 MPG on the 210 and 11 on the 275

[08stroker250]

Usually the hotter your motor gets, the hotter your fuel will get. Normal driving, I see 108-112 typically in 80+ degree weather with high humidity. I don't tow, but I could see where it would get warm. Check your fuel cooler for coolant level. Its the little black "box" looking thing middle/drivers side on the back of the motor. It has a little gray cap on it.

[drservo]

What fuel rail temps is everyone seeing pulling a load?

[Spatel23]

normal driving on the interstate I see 150ish........Ill have that checked over at the end of this month........

[drservo]

150ish on fuel rail temp? Thats no load? Did you just change the high warning on the dash daq and don't worry about it?

[08stroker250]

Originally Posted by drservo

150ish on fuel rail temp? Thats no load? Did you just change the high warning on the dash daq and don't worry about it?

Yea, he did. He has air in the fuel lines somewhere.

[daddystoy]

I was seeing 128-144 EFT1 today drinving from San Diego to Las Vegas. It was 113 out and there are some wicked climbs from sea level to 5000' up 6% grade at 73MPH. Truck only has 3900 miles on it and it was unloaded. It's frustrating. What is the purpose of this anyway? Everyone seems to always be over the threshold of the DD yet no one seems to care. I am just wondering because I thought the truck was going to blow up when the alarm went off at 140. I changed mine to 160 at the recommednation of one of the vendors. BTW, what fluid goes into this fuel cooler? Does the tune really even effect this temp if you are just on cruise control?

[08stroker250]

The same fluid that goes in to the degas bottle. Do a coolant/water mix. I could see the temps getting that hot with the ambient temps being 113 and the motor working that hard. Did they ever get lower than that once the truck settled down some?

[mdavis203]

It could be the fuel coolant pump gone out. That's what happened to me. Feel the fuel coolant radiator after you've been driving a while. It's the little one bolted onto the side of the intercooler. If it's not very warm to the touch, the pump's out.

[daddystoy]

Thanks I will check the resevoir today. I am driving from Las Vegas to Salt Lake City and it will be 110 outside again. Is it just a coolant water mix that goes in there? Does it have to be the same coolant that’s in the radiator? Sorry for the silly ?'s but I have no idea where the degas (over flow reservoir) bottle is or what goes in it. Also, the temp goes down once I am on the road and seems to hover around 128-130'ish. The high temp's are seen after running hard and pulling off the highway for a food or bathroom break. That's when it hit 140-144 just sitting idling. It never went over 150. Does the tune effect that temperature? I can't see how it would since the truck is just cruising.