Ranger Mods

Mines slowly climbed up the past few days and is now sitting on 109% (6 days in Alice, no towing)

Up until now it's always managed itself well, even with the Mrs main use for it being school runs.

Should I be worried?

Will be back on the Hwy tomorrow towing the van toward Tennant Creek.
I'm hoping it decides quickly to do a burn.

it has crept down to about 45% over the last 2 days of driving.
got to 115% before it did though

the burns were only 2 minutes at best each.
im guessing its probably high ambient temp and load that are telling it not to burn?

Possibly Brett, seems no one else has had the same issue.

Back in coober Pedy heading to Melbourne, so next few days the temperature will drop and hopefully back to normal.
Still sitting mid 50%

I don't dick around when I'm towing, and it's got the performance tune in it. Probably all a factor

Mine slowly climbs to 100%, the the DPF temp rapidly climbs to around 600c then gradually cools off over about 15-20mins.

If I am doing around 100kph the temp drops to around 200c

Headed east from Port Augusta to Renmark today.
Loaded up through the hills, quickly burnt down to 19%.

ok, mine again crept up to 147% this time.
spoke to Barry at BPT who said its the latest ford tune doing things different with DPF burn (the 1kph cruise control increment tune, AHY)

I put back in the AHS tune file (the old 2kph cruise control increment tune) and within a minute it started a burn, and in 5 minutes of driving it dropped down to 20%.

Hi mine goes up to 94 the drops down to 22. Is it memt to drop down to 0?

Phillwehbe89 wrote: ↑Sun Jul 12, 2020 8:27 am Hi mine goes up to 94 the drops down to 22. Is it memt to drop down to 0?

I thought it would drop to zero as well, but it varies from what I have noticed depending on speed/load.
Mine drops from 2 to 25%.
On a recent trip towing 2.5 ton @ 104kph the DPF hit 700c doing a burn and it dropped to 5%
Next burn was in the city and it reached 580c and dropped to 21%

Given there's no pressure sensors on the DPF I think the DPF Soot figure is a calculation* based on torque demands and fuel burnt. So it's a guide as to how blocked the DPF is.
EDIT: Yes, there is a single pressure sensor used. It would seem my eyes aren't what they used to be. Apologies for any confusion.

I've been watching a number of DPF burns occur and watching the EGT11/12/13 readings. My interpretation of what happens is that the regen cycle kicks off with some post injection fuel and that brings the soot in the DPF up to ignition temp (EGT11) of 600c. The burning off of the soot is reflected in the EGT12/13 temps (~615c/~550c), and if the EGT12 temp (middle of DPF) drops below 590c, then more post injection of fuel occurs to keep the soot burning. Based on how quickly the EGR12 temp drops the PCM can calculate how much soot exists in the DPF. If the calculated value is low enough, the burn stops. Mine always seem to stop at 25%.
A motor under load will naturally raise EGT's and might make a DPF burn harder for the PCM to calculate and control. My guess is that going above 100% [calculated] soot load is the PCM's way of letting the world know it thinks it's overdue for a burn cycle.

FWIW, FORscan has an option to kick off a manual DPF burn if needed.

EDITED: Ford has form using calculated and contrived values rather than a sensor with their engine management (MAP comes to mind on petrol engines). My exhaust tip is still sootless after 20k km, so I guess the system can work.

There a 2 pressure sensors on the DPF.

saeb wrote: ↑Mon Jul 13, 2020 11:57 amThere a 2 pressure sensors on the DPF.

Stewart,
Just double checked and can confirm there is a single (not 2 like I've seen on many other cars) pressure sensor on the DPF and this matches my scanner software. The sensor is located below the brake booster. I'm pleased I found it because it makes much more sense.

I'll try and edit my previous post.

CatHerder wrote: ↑Sun Jul 19, 2020 6:06 pm

saeb wrote: ↑Mon Jul 13, 2020 11:57 amThere a 2 pressure sensors on the DPF.

Stewart,
Just double checked and can confirm there is a single (not 2 like I've seen on many other cars) pressure sensor on the DPF and this matches my scanner software. The sensor is located below the brake booster. I'm pleased I found it because it makes much more sense.

I'll try and edit my previous post.

> https://www.saeb.net/viewtopic.php?f=63&t=525 < First image here of DPF.

Yep, it shows the single pressure sensor and 3x EGT sensors.

It's called a "Pressure Differential Sensor" so maybe it is already measuring the pressure in two places and reports the relative difference rather than the absolute pressures.

Alternatively the output of the DPF is connected to the atmosphere through a long open pipe (the exhaust) and so the output pressure may be considered known or low enough to be irrelevant, then you only need to measure the pressure at the input of the DPF to determine what the differential is and how blocked it is.