Funny story happened.

 

I've been driving on highway, checking my new ECU remap...swapping screens of Polar FIS box..

 

EGT 800deg C....what the hell is going on at 40% of accelerator pedal. This temperatures usually come at 100% load in mountains and WOT.

 

My first clue was DPF regeneration but there was no light on dashboard. During engine ignition, I can see DPF light so it should work.

 

According to Robert Bosch Diesel Management Book - DPF regeneration suppose to last 10-15 minutes.

 

I changed Polar FIS screen to DPF diagnostic...DPF 10%...7%...3%...0% after about 5 minutes....but EGT remains 800deg C.

 

I drove about 30km/30minutes with EGT 800deg C....interestingly oil temp was around 95deg C. If I push my car hard, it usually goes to 113deg C.

 

 

Could it be faulty DPF regeneration? or my theory is faulty temperature reading or so?

Edited 27 November, 201510 yr by sniper29a

There doesn't need to be a light on the dash for the DPF to be regenerating.

 

The light only comes on when the car needs your help to complete a regen i.e. after several failed attempts.

 

At all other times the regen process is completed without the driver noticing.

Like Silver said, light appears only then when DPF is rather full and you should do something about that. Otherwise you won't even see any lights.

After the regeneration DPF is still hot and probably it takes some time for it to cool down.

I understand DPF needs to cool down but EGT cools down very quickly so DPF regeneration was still running as I suspect. With full load and max Injected Quantity, EGT hits 850deg C. If I decreases load, EGT is down to 600deg C in no time.

 

Point is if you drive 200km and you hit DPF regeneration cycle - your exhaust may melt down. If you have no diagnostic, then you might be screwed. i wonder whether is that ok or something is wrong.

 

I doubt exhaust was designed for such a high temperatures in long term.

Edited 27 November, 201510 yr by sniper29a