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      06-04-2015, 01:45 PM   #31
TDIwyse
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Drives: 2011 335d
Join Date: Aug 2012
Location: MidWest

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Quote:
Originally Posted by 335dwanted View Post
I have a block plate at the EGR valve but not one at the turbo. However, I thought I noticed that EGR Commanded was 0 during warm-up, I will have to look again.

Interestingly, I had a DPF regen this morning and saw quite a bit of vacuum, the only time I have seen negative PSI when warm.

While I appreciate the notion that closing the throttle will pull more EGR, it seems the two circumstances where I have seen a vacuum state are the times when EGR Commanded usually goes to 0; warm-up and regen.
This may be interesting to you. Some old data from stock behavior I had collected back in 2012 comparing EGR and Throttle behavior during drives to work where no DPF regen was occurring and then one with DPF regen occurring.

Also, during warm up there can be some post injection events used, and the EGR position usually closes during post injection events to keep raw fuel from being dumped back into the intake.
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