So I had some time to play at the shop today. I grabed the IDS and starting playing with some active commands and found that when activeing the fan clutch it would NOT run at the commanded duty cycles.

So here is what is going on when I turned the fan on to 100 % duty cycle max fan speed was around 900 rpm with engine at 2500 rpm. What it should... the fan should turn at 2800+ rpm with the engine at 2500 rpm.

I cleard the egr codes from hooked my valve back up and retest. Once the codes were gone and the valve hooked up the fan will now run at 2800 rpm with engine at 2500rpm as it should.

So if you are out there and still with headstuds and running around with an unpluged or no egr valve this may solve your issues.

also as a side note after pluging the valve back in my milage may have gone up a little bit.

 

Very interesting.Gotta a question, in some sort of way does the egr act as a waste gate??

 

Man that a tuff question, but no not really. the egr valve however is used to create back pressure to help spool the turbo. It will also reduce the amount of back pressure to slow the turbo down and reduce boost.
It however is not a "waste gate" used to dump pressure at a quick rate.

 

I was just curious, I was wondering by deleteing the egr valve it would build up more exhaust pressure in egr cooler,thus putting more pressure on turbo turbine not allowing for discharge of pressure when egr valve opens and closes.just thinking again, u could almost smell the wood burnin.Or maybe 2 many of these..

 

Sooo... if I understand correctly you are saying that even though we may have an egr delete we should still keep our egr valve in, and plugged in? I just did a egr delete and left the valve in and hooked it back up as it was unhooked for about the last 4,000 miles before the delete.

So I guess according to your recent data find, this is the way it should be done.
Thanks Cheezit

 

I was running with a blck off plate installed and this is what I found so I cleaned my old valve and back in it went.

Im not sure this effects all years, and all levels of calibration. But I know it will on 06/07 with vxcf9 in them.

 

So as you know I am getting ready to delete the eGR cooler. I have a 2005. Should I leave the EGR valve in and plugged in.

 

I cant awnser that as I have no idea how an 05 will react at this point. you can try it both ways.
I just put mine back in and the fan is working as it now should be for the time at hand.
If you have a person that writes toons you may ask them if they even know of this concern and what they advise.
I would speculate that the 05 will have the same issue. I have no idea what the 03/04 will do as that programing is very different then the 06/07.

 

First off, a big thank you to Cheezit for his experimenting with factory Ford diagnostic equipment and sharing the results with all of us.

You said "I cleared the egr codes from hooked my valve back up and retest. Once the codes were gone and the valve hooked up the fan will now run at 2800 rpm with engine at 2500rpm as it should."

Questions:
1. can we assume that if you had installed a "dummy" EGR valve (EGR valve still installed but EGR plug attached to a different, not installed EGR valve to fool the PCM) that the PCM would command 100% fan?

2. I guess what I am asking, is the 100% fan a result of the PCM sensing the EGR valve is communicating again? -OR- is it a result of the actual exhaust gasses flowing through the system, and the various sensors being 'happy' and commanding a normal strategy. In other words, is it a software issue, a hardware issue, or maybe a combination of both?

If you have an extra EGR valve, maybe you could run the same test again. This time plugging your EGR plug into the "dummy" valve and seeing if the PCM even notices the difference. The reason I ask is that I have read many posts where guys run this way.

 

I am not running tunes but after all is done on the motor I may do that. Wanted to wait until it was out of warranty. I just ordered an Edge Insight CTS it is pretty cool. I bought the probe that you can daisy chain. The guy was telling me that it has the EGT on it and they have the turbo timer for it also that will hook to it. The program is not out for it but will be in a month so I bought it. I am looking forward to seeing the temps before I tear it apart and after.

 

I did this test both way funny enugh. I have a block off plate so I just hooked it up. it did work as it should have once the codes were gone.
I have no egr cooler so there is no exhaust flow to the valve. the pcm had not yet set a code for no egr flow detected. so once that code shows up I will retest it and varify that the fan works correctly with the no flow code.

 

Cheezit, great info. Wish I could buy you a beer. So I will start wiht putting the EGR valve back in after the delete and pluggin it in.

 

Next time your out just buy 2 and drink mine for me.
cheers

 

In the "for what it's worth" department:

Back a couple of years ago, when Matt at Spartan was writing the first tunes for the VXCF5 flash level, he noticed something odd. Turn the EGR off, and the tunes went whacko. Absolutely no repeatability on the mileage gains, problems with the power gains, basically a lot of problems.

Turn the EGR on, and the problems went away. Nobody liked it much, but all his VXCF5 tunes have the EGR turned on.

Seems that when the PCM detected low/no EGR flow, it went into sort of a "stealth" limp mode; poor performance, but no mentioning of that to the owner or the mechanic. This went round and round for months; I'm not sure there was ever a consensus reached on whether or not the problems got worked out.

-blaine

 

Chezit, will the codes on the 03 motor for egr valve disconnected reset themselves once all is reconnected or must they be reset by us. My 03 with a blocked of egr cooler seems to run just fine with the fan functioning normally when I pull the boat during hot weather and hard acceleration. Runs for a couple of moments once I back off then stays off even with only an occasional short run after I pull away from a stop light. No tow or heavy load in the truck and it pretty much never runs. Truck is stock except for coolant filter and egr has a freeze plug in the input side. thanks