I think that clutch is pricy. I'd get a ScanGauge or some other way to monitor before replacing it.
I got curious and just went out to see what mine does. Looking at the fan as wife Rev's her up, I can't see or hear any change in fan speed that goes with engine rpm. Surprisingly, revving while watching fan speed sensor (fan rpm) on scan gauge, there IS a change in fan speed. Truck is good and warm. At idle, I saw 770rpm. A quick rev to 2500-2800 runs the fan up to 1030. If I hold engine rpm there for a second or two, the fan drops back to 830 or so. Too wierd!
Anyway, as you can see an engine rpm increase (quickly from idle) of 2000rpm only raised the fan 260rpm. So if your fan seems to be directly coupled to engine rpm the VDF may be locked up. I don't know what the default position would be if the valve in the VDF fails, but I would expect the PCM to see it wasn't responding to commands and throw a code.

 

That's what I was thinking, but no codes. I'm trying to use my buddys auto enginuity, but it says the code for the Ford bundle expired.

 

So how about this EGR Valve whats the storey with it

An unplugged EGR Valve will affect the Fan


Unplugged EGR VALVE & the problems that follow
https://www.ford-trucks.com/forums/9...egr-valve.html

But if your fan is on all the time somethings wrong be it the clutch or a temp sensor but its not right and your MPG is in the tank


You guys should start watching the FAN RPM now its getting summer lots of action to watch during summer and not much action during winter

As it starts to get Hot outside watch the FAN RPM you will start noticing certain temps and even like speed conditions(slower mph) that will trigger fan RPM to incress.
There all set points that trigger the Fan speed to incress.

Now depending what Threshold you reach the fan rpm may only jump up a couple hundred RPM and then other thresholds that are reached will trigger the FAN RPM to Drasticaly incress
Example would be
90* ambeint temp with A/C on mine fan rpm would be 400-600rpm
But then as the day would heat up at 95* ambeint temp with A/C on it would jump to 800-900rpm
or ECT 218* then BOOM 1500+ rpm

If there were NOT set points for FAN to step up RPM then NOTHING would happen it wouldnt incress cooling as needed



Kinda like your Low Fuel light it gets low fuel it crosses a threshold and turns on the light

Reving the moter isnt what you want I mean it may incress fan Rpm breifly but no not what Im getting at

Like mine at ECT 218* fan steps up rpm to 1400-1600rpm it will maintain that rpm till it cools ECT to 216* at 216ECT it steps down to Normal 400-600rpm AS LONG as NO OTHER THRESHOLD is IN PLAYif another threshold still in play it may only drop to 700-900rpm (like A/C on above 95* ambeint)

You will have to watch your truck for awhile but after awhile you will see fan speed change at set points ( be it a Temp threshold or speed thresehold whatever the case) just like Clockwork

It took me maybe 1-2months to really see what was what watching the fan and temp sensors and speed and then see the pattern

A FAN step is also like 200 or MORE rpm change depending what threshold is crossed

If you see it change like 50 RPM thats nothing a gearshift or like slight engine rev will cause this and is NOT a FAN Step

the numbers maybe slightly diff year to year stratigy to stratigy but you will see

 

I see what you are saying, but if your tranny temp would start to overheat, your fan would come on before 218*F coolant. In your tests you aren't varying enough of the parameters.

Getting data is great, but it is hard for an individual in 1 single truck to test the full range of the PCM's control of the fan. Trust me (or don't - no matter), it is more complicated than single "temperature switch" type activity. There are MANY people that see similar things you are seeing but at different temps.

As for me - I can't even get my ECT to 218 ..............

Not trying to argue, but I believe the technical manuals (even though there ARE documented errors in them).

 

Here is the word-for-word description from page 5-21 in the 2006 PC/ED manual:

By opening and closing the fluid port valve, the PCM can control the fan speed. Fan speed is measured through a Hall-Effect sensor, and is monitored by the PCM during closed loop operation.

The PCM optimizes the fan speed based on the engine coolant temp, engine oil temp, transmission temp, intake air temp, or air conditioning requirements. When an increased demand for fan speed is requested for vehicle cooling, the PCM monitors the fan speed through the Hall-Effect sensor. If a fan speed increase is required, the PCM outputs the PWM signal to the fluid port, providing the required fan speed increase.

 

Exactly YES SIR

I didnt List every senerio I noticed either as there are LOTS
No kidden 2 months for me to see the big picture


I wouldnt even say this was a test
IMO it wasnt a test but just what I noticed as I watched the FAN rpm and thought ok what made the fan speed incress exactly or where was the line drawn

Shure all the thresholds are diffrent stratigy to stratigy MY to MY Gotcha Im with ya

I know the exact temps I saw isnt what everyone would see Just like some trucks Idel at 580 ICP and some idel at 620 ICP Both of which are good numbers



All Good Mark GOOD TALK

Just thought I would post since some are alittle off track in this thread on how its working

I guess I should also say NONE of what I posted is used to trouble shoot the Fan AT ALL

IIRC to troubleshoot the Fan Clutch Must be commanded to 100% and supposed to hit a certain rpm or something like that Bismic Probably has the Number to Hit on that or something like that

 

Im also thinking Vehicle Speed comes into play as well

IIRC 35mph was a threshold over 95*ambeint with A/C on

Just like your saying LOTS of senerios I didnt make a note of it till I saw the same senerio play out the same way a few times

 

Blade, the EGR valve is in the truck as a dummy valve. I only in plugged just to see if it would stop the fan. After that I hooked it back up and cleared the codes for that.

 

So does it sound like I may need a new.fan clutch from the look of things right now? I got a new code for my AE, and will check everything today. What numbers should I be seeing/ looking for?

 

HOLY COW BENNY! You are a busy man! I just had a visual of you toolin down the road with the tunes on (maybe a refreshing beverage too?), one eye on the road, one on the ScanGauge, and one eye (?) on the phone answering tech questions here on FTE! I'm pretty sure I fried a couple of brain cells on my fourth read of this post! I am truly glad you are here, thanks for all your posts!

 

There is a heavy duty option when go to buy the clutch and it seems to blow like crazy at low engine speeds and i dont think its a electronic function as soon as you start driving it go to normal electronic control. Hayden calls it heavy duty the ford guys ask if you have a snow plow option.

 

LMFAO Now thats some funney stuff right there^^^^

And it just might be true if my phone wasnt a POS I gave up trying to use it on here Its not as high tech as most folks now days

 

Subscribed..... I'm Really interested in trying to figure out the whole Fan Speed/Vehicle Speed/ Oil Temp/ Coolant temp/ Tranny Temp/ and A/C Relationships......

Don't Laugh but all this is a bunch of CHINESE to me!!!!!!!!!! Ive really watched my temps After my Top end work on the SG2 and all seems to be alright.. I have YET to hear the fan come on.....

Haven't Hauled too heavy since the work, but I have hauled a 4000# Holiday trailer up some 3km river-hills holding Highway speed and have not seen any crazy temps (198-210ECT, 218-220EOT, NORMALLY 190-198ECT, 198-208EOT With Trailer on level ground)...

I know Delta is kinda high but that is HOT Day (35-3eg Celc) and have been told that a bigger spread is normal with hauling, its when your empty and just cruising that a big spread is a worry....

Just want to figure this out before my head explodes with all the different scenarios that are in relation to the proper operation of the Fan....

From what I have read there is not very much room between the fan kicking in to 1500rpm (215-ish) and when it goes right NUTS at full RPM (218-219ish), Along with when the Thermostat is closed, partially open or WIDE open.....

If the Thermostat opens completely at 215-219, and De-Fueling (again don't laugh not sure what this means) starts at 220-ish, Does this all mean its all a matter of 2-3 degrees before the specific operations happen to cool the motor down.....

Seems to me that I would want the fan to kick in A LOT sooner than 218-ish.... BUT then again I have to remember that there are more than ECT that controls the Fan Speed....

BOOM!!!!!!!!!!!!!!!! There goes my brain!!!!!!!!!!!!! I think I'm gonna get the SG2 to Monitor Fan Speed and see what I see..... I HOPE someone can put this into Elementary Definitions for me......

Is there anything that clears this up in the Tech Folder, I'm not sure/ Not sure if I'm looking in the right spots....

Thanks and SO sorry for being the Dunce in the Thread.....

 

Lots of great fan discussion in this thread: https://www.ford-trucks.com/forums/1...ch-wire-2.html

 

A couple of degrees is probably within their tolerance level. These aren't NASA units.