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So I have my truck back to stock (EGR and DPF installed) and I have reinstalled my minimaxx but have it just monitoring right now, no tune is downloaded. I notice while driving my egt will spike to 1100-1200* occasionally for very short periods of time, maybe around 30sec or so. I imagine that it is part of the regen process but it does it around town too. I always thought that you had to be above a certain rpm for a period of time before any regen would take place.

I did just drive my truck on a 60mile round trip on the highway and it did the same thing. Never did it hold an apparent regen for more than about 30 sec. Also I thought I read somewhere during regen your egt could get super high, like in the 1500* range, I don't think I remember seeing mine anymore than 1300* so far.
 

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A regen will last much longer than 30 seconds and my 2010 would start a regen driving stop light to stop light, but it only really works efficiently at steady throttle because as soon as you let off the throttle EGTs drop. EGTs will only peak if you're steady on the throttle because it takes a little time for them to build up. So any time you let off the throttle they drop and has to build again. This is why the manual says to drive on the highway when you get a % full message to efficiently clean out the DPF. 60 miles isn't long enough to induce a regen, you can go as much as 200 miles between regens driving on the highway. Driving in the city I think will average more around 100 miles. There really isn't set numbers for any of this because (as far as I understand anyways) it's all based on flow through the DPF. If the DPF isn't flowing what the computer wants it'll regen to clean it out. Soot build up is directly related to your driving/how you use the truck.

One way I always first noticed I was in regen is monitor intake temp. Apparently the EGR will close during regen, so intake temp will be 10-20 degrees above ambient rather than in the 100s.
 

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Once regen starts it will take about 25-30 miles at highway speeds to complete. I have boost and EGT guages and generally, on somewhat level terrain, the boost goes to zero and the EGT will go up to 1300-1400 with no load. I've seen 1500 for a long time while under load and pulling hard enough to need boost.
 

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Also, a regen can happen anywhere. It's not something that only happens on the freeway, it'll happen around town, idling, etc. 1100-1200F EGTs are what you'll see during a regen as well.
 

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My truck goes only to 1050* during active regen on consistent basis. Once I seen it go up to 1200* going up the Grapevine on I-5 (unloaded).. My regens last around 15-20 min at constant highway speed w/o interuption. I deleted for a while, and went back to stock. The first regen lasted around 60 miles of my 90 mile trip on the freeway w/ the first tank back to stock.

Now it's back to normal 15-20 min regen approx every 100-150 miles after the first tank. It seems my mileage went up after flashing my truck back to stock when I was using the Smarty Jr.. Not in regen my EGT's between 600*-800* freeway speeds,. and 500*-600* driving city style...
 

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My truck goes only to 1050* during active regen on consistent basis.
What are you using to check EGTs? Do you have analog or digital gauges with a probe or are you monitoring a specific PID with digital gauges via the OBDII port?
 

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Isspro EV2 EGT guage.. Probe mounted in the manifold collector (same spot as my '05).
 

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Isspro EV2 EGT guage.. Probe mounted in the manifold collector (same spot as my '05).
That's likely the difference. Monitoring the NOx or DPF EGT sensors it's common to see 1100-1200F via the OBDII port.
 

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What are you using to check EGTs? Do you have analog or digital gauges with a probe or are you monitoring a specific PID with digital gauges via the OBDII port?
I have exactly the same experience as firemansdiesel. I usually have the EGR unplugged which makes all temps lower though.

Active regen (as indicated by my Edge Juice with Attitude reading the OBDii port) only raises the EGTs to about 1000F running empty on the freeway. Around town it will be closer to 600 and it will eventually drop to 400 if I am waiting at a long enough light idling in drive.

When I am not in regen, EGT runs about 250/300 idling at that light, 500 around town and 600-700 unloaded on the freeway.

If I plug in the EGR then those values are more like 400, 700, 900 not in regen and 600, 800, 1100 in regen (but it regens much more often with the EGR plugged in).


I monitor EGTs very closely using the juice (digital) from a pyro drilled in the prescribed location in the manifold just where the little dimple is by the pipes coming together.


Leaning hard on the skinny pedal can make the temps go up to 1300F+ briefly. But regen doesn't produce as much temp as I understand others reporting. OTOH my regens seem to work. My regular commute is only 10 miles and I don't get out for longer trips nearly often enough for my own sanity yet the regens usually complete within the 10 miles and I have *NEVER* seen anying on the overhead about the DPF.
 

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That's likely the difference. Monitoring the NOx or DPF EGT sensors it's common to see 1100-1200F via the OBDII port.
This is what I was wondering. If regen causes an extra injection cycle that results in raw fuel going out the pipe then is it intended to burn when it gets to the dpf? Maybe my visible increase in temp is not indicative of the resultant temp increase in the DPF.
 

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One eye opener I had, when I went from stock to deleted. When I let my turbo cool down for min after a trip. The EGT in stock form, I would never get below 400* (just shy of it) unless I was in regen, and the EGT's would be around 500*-600* when I shut the truck down. When deleted, my EGT would drop to 300* in a few seconds. My '05 would not drop that quick...lol

I feel the EGT probe in the manifold is the most accurate way to determine your EGT's... Just my $.02...
 

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This is what I was wondering. If regen causes an extra injection cycle that results in raw fuel going out the pipe then is it intended to burn when it gets to the dpf? Maybe my visible increase in temp is not indicative of the resultant temp increase in the DPF.
Correct, the raw fuel going out the manifold isn't burning yet, what triggers the DPF burn is the DOC. The raw fuel particulates trigger the catalyst reaction in the DOC which raises the EGTs and oxidizes the particulates in the DPF to clear it out, so you won't see the highest EGTs at the manifold but instead you'll see them after the DOC.
 

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One eye opener I had, when I went from stock to deleted. When I let my turbo cool down for min after a trip. The EGT in stock form, I would never get below 400* (just shy of it) unless I was in regen, and the EGT's would be around 500*-600* when I shut the truck down. When deleted, my EGT would drop to 300* in a few seconds. My '05 would not drop that quick...lol

I feel the EGT probe in the manifold is the most accurate way to determine your EGT's... Just my $.02...
If you're running a tune and are worried about excessive EGTs then there's no doubt a pre-turbo probe is the way to go. I simply use the stock EGT sensors to determine when I'm in regen, since I'm not running a tune I'm not worried about cooking my turbo.
 

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One eye opener I had, when I went from stock to deleted. When I let my turbo cool down for min after a trip. The EGT in stock form, I would never get below 400* (just shy of it) unless I was in regen, and the EGT's would be around 500*-600* when I shut the truck down. When deleted, my EGT would drop to 300* in a few seconds. My '05 would not drop that quick...lol

I feel the EGT probe in the manifold is the most accurate way to determine your EGT's... Just my $.02...

I'm not deleted but experiencing about the same thing with the EGR unplugged. I have my turbo timer set to run until the EGT is below 400. It has only once run with the EGR unplugged and in that case I had been in regen and shut down pretty fast and the timer ran for just a few secs. With
EGR plugged in it runs almost every time, sometimes for quite a while.
 
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