Anyone know what our fuel temp should be?

[MMLMM]

Normal around town driving in 65* weather?

My temp when my truck is normal is 150ish

but when I have my high rail pressure (29,000psi) condition, the fuel temp is at 205*

(*F), not Celsius.

 

[skintback]

Reading off a ppe programmer my fuel temp would run around 130 in 85 degree weather driving easy. If i would get on it a few times it would run up to 150+ with 22-23K rail pressure.

 

[MMLMM]

I unpluged the fuel filter assembly heater and now fue is hanging around 120*.


School Me: What would too hot of fuel do to our trucks? Think thats whats causing my issue? Maybe fuel gets hot, reg opens up fully to move fuel through...???

 

[SmokeShow]

it physically loses some of it's energy potential when it's too hot... I believe there is a limit for how cool it should be as well though... can't remember any specific numbers though.

This should be interesting.

 

[SIKDMAX]

theres some thread on this that was just talked about last week... I dont remember where. Search around a little Im sure youll find it.

 

[Dan@PPE]

does it change the high pressure problem. It makes sense, When you compress anything it will get hotter. Full Fuel pressure = hot fuel.

 

[MMLMM]

does it change the high pressure problem. It makes sense, When you compress anything it will get hotter. Full Fuel pressure = hot fuel.

Heres the wierd part dan. The fuel temp is measured on low pressure side. When I unplugged my fuel heater the temp would not go above 130*. It seems the the problem I'm having the fuel goes up to +180ish* and then I get the problem and the fuel temp climbs to 205*.

I am thinking the high temp fuel is causing the problem. The other guy that had identical problem, said he had a shorted wire on the fuel temp sensor....

Anyway, I think my fuel heater is staying on and heating the fuel up, causing this condition. Once uppluged, I get no condition and heat stays around 120* even when I am getting on it pretty hard around the city.....

Also my filer/heater assembly has diesel all over it, I think that has something to do with it, gonna test and see when ot cools down.

 

[hondarider552]

i see 115-130* here in az temps in the mid 70's. i also have the transferflow, which basically blocks air to the cooler.

 

[Mike L.]

Normal fuel temps in summer are 130 to 145. Anything above that and you start losing power and mileage. 205 almost puts you at fuel temp hot mode where ECM pulls back fuel and timing. Ideal fuel temps in normal weather would be ambient, but that is hardly achievable. 100F is ideal.

 

[MMLMM]

Normal fuel temps in summer are 130 to 145. Anything above that and you start losing power and mileage. 205 almost puts you at fuel temp hot mode where ECM pulls back fuel and timing. Ideal fuel temps in normal weather would be ambient, but that is hardly achievable. 100F is ideal.

I agree Mike, I think my truck goes into hot mode around 180*.... I am only experiencing this condition when fuel temp reaches 180*ish.

So far un hooking the fuel heater has droped my temps to 120*, I am thinking heater is stuck on because it should shut off after the fuel temp is 70*.

 

[Dan@PPE]

Interesting...

 

[MMLMM]

Interesting...

yessir, call me some time tomorrow if you get a chance. Id like your thoughts, lol.

 

[LarryJewell]

Normal fuel temps in summer are 130 to 145. Anything above that and you start losing power and mileage. 205 almost puts you at fuel temp hot mode where ECM pulls back fuel and timing. Ideal fuel temps in normal weather would be ambient, but that is hardly achievable. 100F is ideal.

isnt some kind of fuel cooler available

 

[Mike L.]

isnt some kind of fuel cooler available

I can set you up with a fuel cooler but if Mike has a heater problem it won't help much.

 

[MMLMM]

looks like problem solved.

Fuel heater never shuts off.

I need to figure out what commands it to stay on because its not the heater itself, the plug has 12v to it all the time, hot, cold, on, and off....