Originally Posted by Rocksfly
MY14 Laredo @ 26500kms and we have never seen or noticed a regen occur. .
Love the vehicle mostly country miles........ Wondering why I have not seen a regen and does this suggest the filter has never been cleaned.
It will have done a regen (quite a few of them) without you noticing.
Even driving a highway cruising speeds we've observed the exhaust is still too cool to completely burn away accumulated soot in the DPF. A long highway drive might still accumulate some soot albeit at a slower rate than a short trip to the shops from a cold start.
The DPF does not hold much at all , (I'm guessing something of the order of only 50grams). I've done a regen every 10 days or so recently, some longer trips but more short ones <10km.
Originally Posted by Hughesy1991
This is my first post to this thread - I've found some great replies so far. I've had my Grand Cherokee Blackhawk since December - I had the dreaded "DPF Filter Full drive at highway speeds to remedy" randomly pop up before I could do anything else within seconds it threw the car into limp mode - without knowing much about what was going on I got the car towed to my local Jeep workshop where they performed a manual regen and upgraded the software to the latest update which is supposed to fix the issue. I haven't had a problem since touch wood. Although tonight after pulling into my driveway after work I noticed the familiar burning plasticy smell coming from the rear (which is what happened last time before the car went into limp mode) so tomorrow morning will be interesting. I've spent 70% of the time driving this car on the highway at speeds of over 100kmh. The most frustrating thing is it doesn't tell you if it's doing a regen - surely Jeep can implement this with a simple message that says "Regen in progress ___ per cent complete..."??
Quick question - is it bad for the car to shut it down while doing a regen? Surely you can't always know if it's doing one or not??
Apart from that I absolutely love the car - the scariest thing is not knowing if it's fixed and what if you're in the middle of no where? So far after reading responses everyone that has had the latest software update haven't had any issues so hopefully it stays that way! Will keep you guys posted.
We don't know exactly what was changed in the software update, but the situation where the "warning" and the limp mode are triggered virtually simultaneously is obviously wrong. Active regens might be triggering at lower soot loading than before? or they might have delayed the setting for the limp mode because it was programmed incorrectly coming on too early?
We've observed several active regens in this thread which are triggered at 65% full when on the highway or seemingly at around 71-73% when in slower traffic. I'm assuming 80% is when the message comes in.
Stopping a regen (without the message) while it's in progress I wouldn't expect to cause a problem, unless you park the car on some long dry grass
with a 600degC exhaust.
I know, I've aborted 3 regens when partially completed. The soot will have started to burn away soon after beginning, so it will have reduced load but might not fully burn to a "clean" filter.
I had one today that started during a 7km trip it only went for about 7-8 minutes and burned from 72% down to 15% (measured with an OBD adaptor and smartphone app). Running through the full automatic sequence will burn down to about 8%.
I read that back when Ford introduced DPF to some of the pickups in the USA (2008-09 ??) they used to have a message every time the truck did a regen and they used happen quite often as they were just on an hour-meter rather than with DPF differential pressure monitoring. American drivers thought that there was something wrong with their truck.
Car makers generally would prefer that you didn't know
when it was happening and "wasting" fuel.
Really enjoying my Jeep too. I missed it in the last few days as I've been in Tassie with rented Mistubushi Outlinder. Petrol so no DPF but no torque
. Glad to hand it back and retrieve my Jeep from the airport.