When I get my truck back, I am going to run a set of my own tests on this EGR issue. I feel between the terrain of this area and the way I drive should really be able to extract some decent data once i get my gauges installed.

Ill make runs for boost and EGT with the EGR hooked and unhooked. Im not sure if tailpipe emissions can be measured on a diesel, but my uncle runs a shop that does state inspections, and if it is possible, i will have him check and see if a significant difference in emissions is present, for all you cali boys

 

I unplugged mine and the truck seems to come off of the line faster less turbo lag,the one thing I noticed is,it has less smoke on start up and less smoke on heavy acceleration.fuel mileage is about the same though so far.

 

this is a excerpt from "dieselmans" ford bulletin page:

Normal EGR Valve Operation--Open at Idle:
Trucks built after 9-30-03 and those truck reprogrammed with WDS version 27.9 or higher will now have the EGR valve open at idle. This is to reduce engine noise at idle that has occured from removing the pilot injection. When diagnosing the EGR valve it is normal for the valve position value (EGRVP) to not change until the EGR duty cycle is greater than 30%. Broadcast Message 1067

 

BTW, for those not in the "know", ver 27.9 was a LONG time ago like way back last summer

 

Same result here.

 

Interesting peice of information. Might explain why some claim it makes thier motor louder, and some the opposite. No explanation for the opposite but I may be overlooking something. Mine did'nt seem to change at all.

 

just tryin to help out ur thread, bud

 

Good work, thank you.

 

BTW, i checked this out today and (by ear) it definately is louder w/ it unplugged. a lot louder at idle. no noticable difference any where else.


although this may be in the calibration difference in my 550 as compared to the 250's and 350's

 

Actually, I forgot I had unplugged it...
Haven;t noticed much difference since then...
may take a moment to record the plugged vs unplugged volume to test it...

 

Just curious....

By disconnecting the EGR, will performance suffer in the winter when the air is cooler or very cold?

Does the recirculating of warm/hot exhaust gas help with fuel ignition or burning in cold weather? On my old 1972 Chevy Nova, there was a hose from the air-filter inlet to the manifold so it would draw in warm air... then when it warmed up, a flapper openedon the aircleaner and let in fresh and or cooler air... but the warmer air helped in cold weather starts and running.

So, in short, my question is: "What affect will we have by disconnecting the EGR valve in cold weather operation?"

Thanks,

Jeff

 

Someone else may have an answer to this; I do not. The colder the intake air, the better the engine will run. This is assuming that the engine is already running. As for your question on cold starts, I would say, judging by the information just provided by BigHoss550, this would only effect the trucks that open the EGR valve at idle to help quiet the engine down. I would speculate that this might help the engine warm up negligibly quicker, ASSUMING that your truck has the program that will allow it to do so. IMO the benefit of a cleaner burning engine outwieghs any downside by means of cold starts. That is the job of the glow plugs.

By the way, how cold of a climate are we talking here?

 

Kansas City area (Midwest).

Low side maybe -20 or so windchill with a constant temp of 0 (zero or so for a week).

Thanks,

Jeff

 

I suppose the difference would be discussable/debatable at that temperature. That is quite cold, however the glow plugs are *rated* at -10dgf. What is the build date of your engine?

 

Two things to consider here. First is that the air gets heated when compressed going through the turbo. That is one of the reasons for the intercooler between the turbo and the engine manifold, to cool that compressed air. The second is that there is an EGR cooler that is used to cool the exhaust gases before they are sent to the EGR. Page 37 in the 6.0L Bible.

Another thing to consider is that your old Chevy Nova had a "normally aspirated" (as opposed to turbocharged) engine that sucked the air into a much lower compression cylinder and needed that warmer air until the engine heated up.