Fuel Temperature

[Me78569]

vehicle profile selected is what defines what sensors are able to be choosen.   MAke sure you setup your vehicle correct.

[LorenS]

I made sure. Unless there's something else to do besides check the 01-02 Dodge option. Still no Timing. Nor ECO, for that matter.

[Mopar1973Man]

1998.5 to 2002 Dodge 2.7 is the right one...

 

[LorenS]

Thanks, I found that late last night when I returned home.  Didn't know to scroll down past the Ford listings to find V2 listings.  The gauges were there for my drive in this morning!  I did some data logging this morning now need to make a spreadsheet to plot it all, I guess.  My EGTs seem high for flat ground, wondering if my timing needs to be adjusted to compensate for possible wear in my VP44 (previous owned had 36k pound license plates and scrapped heavy iron).

[Mopar1973Man]

80 mile round trip to McCall ID, cruise set for 65 MPH. 

 

Just update with current trip. As I said high fuel temps are not normal.

 

NOTE: Transmission Temperature is actually Engine Oil Temperature.

[LorenS]

I understand the fuel temps are high.  Plan to change "screen" filter ahead of lift pump and the fuel filter.  I unhooked the fuel heater as you suggested, made no difference on my 350 mile trip home yesterday.  I know you've got much larger and higher pop injectors than my stock remans. That should reduce the VP44 computer heat, right?

I must be getting some decent flow through my VP44 because it took 200 miles for the fuel temps to rise after fueling up; it was a slow climb from ~85 to 142.  Nice, cool, fuel from underground tanks sure helped!  But if there was very limited flow through VP, that shouldn't take nearly 3 hours for the fuel to get hot.

 

Is it possible my VP44 is so worn that it's "churning" the fuel, causing substantial heat and possibly also has (for lack of a better term) "blowby"?  My EGTs on flat, Iowa interstate with no head wind just seemed very high yesterday.

 

Side note, why does the yellow turbo warning symbol show up almost every time?  When I restarted the app after filling up, I drove the remaining 250 miles without that symbol popping back up.

Here is part of my datalog graph from this morning after I discovered the correct V2 vehicle setting; yellow turbo warning popped up this morning, too!  I don't have NEAR as much timing as you do.  Fuel temp here as already to 128 about 15 minutes into the drive. Low-80s this morning when I drove in.  The weather here is awful...

Edited July 8, 2020 by LorenS

[Mopar1973Man]

 

36 minutes ago, LorenS said:

That should reduce the VP44 computer heat, right?

No fuel pressure. Fuel pressure that is above 14 PSI keeps the overflow valve open and the VP44 cooled off. Fuel pressure is the solution here typically. Still running the same old AirDog 150 with a 165 AirDog Pump head. Fuel pressure is never below 15 PSI.  But idle is 17 PSI.

 

 

Edited July 8, 2020 by Mopar1973Man

[NIsaacs]

Just hauled two loads of cinders, 36 mile round trip, ambient is 95*, little over a half a tank of fuel, it was 106* with IR gun. My street is 1/4 mile, I shut the AC off at my short drive way. At shut down 300* EGT, 181* coolant, fuel temp 152*, IAT 141*. This is with the Edge touch screen monitor, probably some difference from the Quad. 

 

I have another load to haul tomorrow, I will fuel up and check it again. The AC raises my IAT some, especially at slow speed. 

[Mopar1973Man]

14 minutes ago, NIsaacs said:

he AC raises my IAT some, especially at slow speed. 

Actually no, its the lack of boost pressure. When I'm dogging along in McCall at 25 MPH my IAT rises slightly maybe 5*F tops.  Once I get back to highway speed again and boost pressure is about 5 PSI my IAT temps falls again.  Air Conditioning has zero impact really for my truck. Just the engine load rises 2% that's all. No change in coolant temperature, no change in IAT or Engine oil temperature. 

[NIsaacs]

6 minutes ago, Mopar1973Man said:

Actually no, its the lack of boost pressure. When I'm dogging along in McCall at 25 MPH my IAT rises slightly maybe 5*F tops.  Once I get back to highway speed again and boost pressure is about 5 PSI my IAT temps falls again.  Air Conditioning has zero impact really for my truck. Just the engine load rises 2% that's all. No change in coolant temperature, no change in IAT or Engine oil temperature. 

 

 

What about idling with AC on for say 10-15 minutes? Mine goes up to about 140. Cruising down the highway it drops down a bunch. I assume it is the condenser heating the CAC at idle?

On a long down grade with a load and exhaust brake on I have seen it at 160-170*. The higher the RPM/back pressure, the higher the temps. 

[Mopar1973Man]

1 minute ago, NIsaacs said:

What about idling with AC on for say 10-15 minutes? Mine goes up to about 140.

Again because there is no boost pressure to move air. Heck all I got to do is turn on my exhaust heading down hill and I can push IAT past 140*F easy. It nothing to worry about. Again once I'm back into boost pressure the IAT falls back down. Yup like you typically high RPM exhaust brake usage will push quite a bit of hot gasses back in the manifold as the exhaust brake is running. 

 

3 minutes ago, NIsaacs said:

I assume it is the condenser heating the CAC at idle?

Well a bit but again there is no air flow of the grill area other than the engine fan which typically is not fully locked. I don't count idling temperatures because the truck is not moving through the air. 

 

Typically my fuel temperature and my IAT temps chase each other. Within about 5 degrees tops. 

[NIsaacs]

Fueled up first thing and drove to the pit, 26 miles, slow paved road, 35-50 mph. At the pit, 78* ambient, first picture, no AC.

 

Return trip loaded, 85* ambient, second picture, no AC.

 

After two complete round trips, 96* ambient, third picture, AC on.

 

At cruise, 50 mph level road, 6 psi boost, 750* EGT, 78* ambient, IAT 115*. Same cruise, AC on, ambient 96*, IAT 131*.

 

All pictures, stopped and Idling. 

 

 

[Mopar1973Man]

How much fuel is in your tank on the last photo? 

What is your fuel pressure while rolling under load?

[LorenS]

On 7/8/2020 at 1:05 PM, Mopar1973Man said:

Fuel pressure that is above 14 PSI keeps the overflow valve open and the VP44 cooled off.

I understand that's the consensus.  However, if your truck requires less pulse-width of the solenoid, then that should reduce the average amperage through the computer, thus reducing heat load.  That's all I meant.  Kind of like the logic of take lift pump power draw away from the ECM by use of a relay, thus reducing heat in the ECM and hopefully extending its life.

[NIsaacs]

2 hours ago, Mopar1973Man said:

How much fuel is in your tank on the last photo? 

What is your fuel pressure while rolling under load?

 

I am at 3/4 tank, 140 miles but 5 hour run/idle time, never shut the truck off. The AC was on about 3 hours. I am at 10-12 fuel psi at cruise power, 7-8 wot. I started with 70* fuel temp at 0700 hours this morning and shut down a little after 12. I was going to check fuel tank temp but forgot.

Edited July 9, 2020 by NIsaacs

[Mopar1973Man]

32 minutes ago, NIsaacs said:

I am at 10-12 fuel psi at cruise power,

You losing the cooling ability of the fuel. The overflow valve is closed. When fuel pressure drops below 14 PSI the overflow valve is closing by the time its getting to 10 PSI its completely closed. 

 

33 minutes ago, NIsaacs said:

I was going to check fuel tank temp but forgot.

Good idea...

[NIsaacs]

Yes, I figured as much. I don't normally pay much attention to those two gauges, I can hardly see them. The main ones that I do watch, I have enlarged.

 

 

When my VP or lift pump goes I will upgrade to the Raptor 150. Not sure why I bought the 100, it is for a stock truck but it has been a good one. I went through several stock ones, 1 Airtex, 1 Fass DDRP and now this for 4 years. The old VP keeps on a tickin, 344k so far.

 

Picture of my tranny temp, about 160* but I never got above 5th gear. I have a tough 47 mile uphill haul I do about 4 times a year for 3 days and it will get up to 190 but 6th gear all the way. On a really bad windy day it got up to 210 so it was pulling harder or the wind disturbs the flow around the tranny. I was surprised at that. A two lane 65 mph road will run hotter than the freeway at 75 mph. I think that has to do with the air flow.

 

 

[Mopar1973Man]

Just did another Trip to McCall which turned out about 80 miles. Still only 110*F with nearly 80*F temps out. Climbing a 7% grade at 45 MPH, and open flat running at 65 MPH. My truck was already warmed up some from a previous trip down to my other shop for a quick starter fix for my Landlord. 

[wish4hemi]

I have another data point to add here for whatever it's worth. On a 7-hour trip through Missouri and Arkansas with an 8,500 lbs camper on, averages were ambient 75*F, engine coolant 195*F, NV4500 190*F, fuel temp 130*F. This is on Level 1 on the Edge JwA, stock Carter in-tank fuel module with stock return into the basket. The supply line is Evil Energy 3/8" braided hose all the way. Fuel pressure is a steady 18 psi.

[Mopar1973Man]

Just a couple days ago we had a 100°F day my fuel temp floats 120°F only the engine returns to OE basket, AirDog 165 GPH draw straw outside the basket. The AirDog returns to the filler neck. Fairly steady at 17 PSI. Trip was 40 miles round trip to New Meadows and back home. Also fuel temp and IAT typically match. Climb to New Meadows roughly 1,000 foot climb. Quadzilla set on CanBus only (Lvl 3) no wiretap. Weird on is at 66 MPH, 2000 RPM, 550°F EGTs, 2-3 PSI of boost, but dropping 24 degrees advance at the speed pushing 22 to 25 MPG.