Well I'm not that new to this diesel.

The block heater is already hanging out the grill waiting for it to get cold.

I was more wondering at what temp the fuel heater becomes necessary and does it need to be on the whole time or just for the first 15 minutes or so until the vehicle reaches normal operating temperature?

Jason

_________________
1998 TJ Gasser - Just for fun!

Sold in January 2012:
2005 Sport CRD
New to me March, 2007 w/22k miles
165,000 miles and still going strong
Factory Tow Package, Added Courtesy Lamps,
New Style Mopar Fuel Head,
Cooper Discoverer ATR
Mopar Slush Mats (JUNK!), Fumoto Oil and T-Case Drain Valves

One never knows where to begin!

I believe......that the heater is set to turn on around 55 degrees and off at around 85. It then tries to maitain temps above the 85 degree range, of the fuel not ambient.

_________________
Dave

'06 CRD Limited, Lt. Khaki, MOPAR Slush Mats/Skids, DrawTite Front Hitch, Mag Lite, Yakima Bars, Thule Bike Rack, Fumoto, ORM, 245/70 Revo 2

Wish list: Lift, Boulder Bars, Something Bigger in the Front and Back, More Lights

Fuel doesn't begin to ice up till well below 30degF - the 12volt fuel heater is intended to get fuel temps above the icing point, and it is t\c controlled to cut off above a fixed point - 85deg seems kinda wasteful.

The in-block coolant heater is intended to assist cold-weather starting by warming crankcase oil and block temperatures, such that the starter has less load and cold Diesel fuel will combust easier - down here below the 'don't snow much down here' line, I plug the ac heater in when temps drop below 45 deg, having older Diesels to contend with.

You can use a refrigerator\appliance timer, such that the ac heater is switched on, say, two hours B4 you intend to leave - and longer, the colder it is - and the engine will be warm enough to start easily - you'll need to be the final judge of that - only snow I see down here is in the freezer, when something's been in there too long.......................

_________________
'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go

Well here is a question, unplugging the fuel temp sensor causes a check engine light, but does it do anything else?

IE could we unplug the temp sensor, and put a resistor in its place to trick the ECU into thinking that it doesnt need to run the heater, that way we would be able to leave it plugged in to keep it from leaking out the plug, but not have it come on.


This would only work if the ECU does not need a correct reading of the temp from the incoming fuel to run correctly.

_________________
http://www.Colorado4Wheel.com
"Its not about what you can DO with your Jeep, its about where you can GO with your Jeep."
Knowledgeable - But Caustic

Ah - I thought that might be a problem - ECM uses the inlet fuel temp sensor to control rail pressure - if inlet fuel is too warm, pump flow rate to the rail is reduced such that there is less overflow from the injectors, where fuel temps are at least engine coolant level - 195degF

The fuel heater is only to prevent fuel-icing - fuel heaters usually have their own built-in t-stat, and this one does also, in the heating element - on at 45deg and off at 85deg - no ECM control - power is always applied at key-on, but element is non-responsive until below 45degF - off temperature is the temp of the element, not surrounding temps, so it only heats in cold fuel conditions

_________________
'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go

So...
When I unplugged mine today I had a small hiss of air as well as a samll amount of fuel release from the plug.
I noticed the plug was scorched and came inside to post my earlier reponse to this thread.
A few hours later I tried to drive away and the engine died about 5 seconds after I started it.
I wasnt able to get it to restart.

Well, remembering what other said in this thread about an air bubble in the head causing the problems in the first place, I grabbed a wrench and re-primed the system. After about four repititions of pressurizing and cracking open the valve to release air I had it re-primed.

After that it started right up.
I am definitely getting air in my filter.

1) My coolant level seldom gets above 180 degrees.

2) I don't claim to be an expert here but I believe it was MrMopar who offered that the heater had as much to do with getting the fuel temp up to optimum temperature for engine performance as icing.

_________________
Dave

'06 CRD Limited, Lt. Khaki, MOPAR Slush Mats/Skids, DrawTite Front Hitch, Mag Lite, Yakima Bars, Thule Bike Rack, Fumoto, ORM, 245/70 Revo 2

Wish list: Lift, Boulder Bars, Something Bigger in the Front and Back, More Lights

Since fuel is leaking thru the heating element, air can enter there, also, resulting in siphon-back to the fuel tank, which is lower then the fuel-manager head - temporary solution would be to pull the fuel heater relay so there is no power to the plug and install the connector, hoping the weather-pak seal would prevent leak and drain-back until you can get it to MrMoservice

_________________
'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go

Me, too, Dave - my take is, off temperature is 85degF, so element should stay on till then, but will not turn on at 50degf, for example - also, the IP quickly warms up to engine operating temperature, and the engine bay warms up, which helps with fuel temperature

So - how does the element work if fuel is at 40deg, element is on until close-vicinity temps are 90deg from engine radiation, element goes off, but ambient-temp fuel is now 10deg above the on-point, at 50degF - will the element attempt to supply heat?

_________________
'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go

One note, while I may know who you refer to by MrMoservice, you may need to be careful as to not confuse people with our very knowledable member MrMopar, doing so could create alot of confusion and trouble for him.

_________________
http://www.Colorado4Wheel.com
"Its not about what you can DO with your Jeep, its about where you can GO with your Jeep."
Knowledgeable - But Caustic

Remember that you have the pump using only a fraction of the fuel it is demanding (unless it is full of air ) and returning it to the tank at very high temperatures. So ultimately the pump is the primary fuel heater after you have been running for a while.

_________________
Dave

'06 CRD Limited, Lt. Khaki, MOPAR Slush Mats/Skids, DrawTite Front Hitch, Mag Lite, Yakima Bars, Thule Bike Rack, Fumoto, ORM, 245/70 Revo 2

Wish list: Lift, Boulder Bars, Something Bigger in the Front and Back, More Lights

Woops! Hope that's not the reason he hasn't been responding, as of late - altho, I frequently reference his input as MrMopar.

MOPAR: DCX, Jeep, Dodge, and the other stuff with wheels

Service guys are MrMoservice

Parts guys are MrMoparts

Janitor - MrMofo?

_________________
'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go

gmctd

Speaking of PARTS gmctd, we were discussing the FSM and part numbers. They are on virtually every page once you get past the first couple of diagrams and indexes of each sub section. Page 448 has most of the emission system part numbers for instance.

_________________
Dave

'06 CRD Limited, Lt. Khaki, MOPAR Slush Mats/Skids, DrawTite Front Hitch, Mag Lite, Yakima Bars, Thule Bike Rack, Fumoto, ORM, 245/70 Revo 2

Wish list: Lift, Boulder Bars, Something Bigger in the Front and Back, More Lights

Thanks - I still have not found that in the downloaded manuals, or the 45RFE excerpt from another post - I usually reference the '06 manual, as the '05 was published in '04 so would have none of the '05 updates

Maybe the PDF version is lacking? I'm running Adobe reader v7.x in XP s.p.2

_________________
'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go

He only pops in occasionally, so I doubt that has anything to do with his absence or presence.

_________________
http://www.Colorado4Wheel.com
"Its not about what you can DO with your Jeep, its about where you can GO with your Jeep."
Knowledgeable - But Caustic

I only downloaded the '06 PDF. I am running 7 or 8 but that shouldn't be an issue as it is just printed on each page.

_________________
Dave

'06 CRD Limited, Lt. Khaki, MOPAR Slush Mats/Skids, DrawTite Front Hitch, Mag Lite, Yakima Bars, Thule Bike Rack, Fumoto, ORM, 245/70 Revo 2

Wish list: Lift, Boulder Bars, Something Bigger in the Front and Back, More Lights

That appeared to be the case - thanks for the input, Sam.

Pg448 in the PDF ver is Lamps - Lighting and Exterior in '05 - '06 is Brakes - ABS Electrical Diagnosis

_________________
'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go

This is my page 448 in the PDF '06.

_________________
Dave

'06 CRD Limited, Lt. Khaki, MOPAR Slush Mats/Skids, DrawTite Front Hitch, Mag Lite, Yakima Bars, Thule Bike Rack, Fumoto, ORM, 245/70 Revo 2

Wish list: Lift, Boulder Bars, Something Bigger in the Front and Back, More Lights

That looks to me like the official parts manual, which I have looked thru - across the counter with MrMoparts

I see nothing like that in the files I downloaded - it is also not on the DCX cd - is that stuff in the .DMG file?

_________________
'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go

Have you filed a claim with NHTSA
Here's the link I got from another thread. http://www-odi.nhtsa.dot.gov/ivoq/
There is a active investigation going on now

_________________
Atlantic Blue 06 CRD Limited (his)
Joined by a 2000 XJ Classic (hers)