Black Smoke on hard accelleration or under load

rovertone · 19th July 2017, 23:11

My car runs an absolute dream, has 160 remap and have just completed 3K round trip to Algarve achieving 43.5mpg at a fairly rapid pace and fully loaded which I think is acceptable for an auto. Mileage 128K

My problem, as the title suggests, is a black smokescreen when I boot it hard which clears as soon as I ease to cruising. This is also noticeable when under load towing my caravan. I can be climbing an incline at steady throttle and all is ok, if I put on a bit more power I get black smoke, ease off and it disappears, on and it returns.

I have had this problem more or less since I had the car at 92K (pre remap), there has always been a soot mark on the rear bumper after a long run. I would certainly have failed the last 3 MOT's on smoke emissions had it not been for a 'friendly' tester.

I have done all the usual items, new MAF (didn't real need it), upgraded PCV, cleaned out EGR & manifold, I/C hose all good new 'O' rings fitted, new air filter, fuel filter, replace stat & water pump (engine now runs correct temp).

Not sure where to look next, as stated the car runs really well but given the focus now on diesel emissions I am thinking that my MOT man may not be able to be so 'friendly' in future so need to try and sort this.

Maybe a T4 health check? Nothing showed up on remap at c96K.

Any suggestions would be most welcome
Thanks Tony

19th July 2017, 23:11	#1
rovertone Gets stuck in Rover 75 Conne SE Auto CDTi Join Date: Nov 2012 Location: Redditch Posts: 670 Thanks: 185 Thanked 135 Times in 109 Posts	Black Smoke on hard accelleration or under load My car runs an absolute dream, has 160 remap and have just completed 3K round trip to Algarve achieving 43.5mpg at a fairly rapid pace and fully loaded which I think is acceptable for an auto. Mileage 128K My problem, as the title suggests, is a black smokescreen when I boot it hard which clears as soon as I ease to cruising. This is also noticeable when under load towing my caravan. I can be climbing an incline at steady throttle and all is ok, if I put on a bit more power I get black smoke, ease off and it disappears, on and it returns. I have had this problem more or less since I had the car at 92K (pre remap), there has always been a soot mark on the rear bumper after a long run. I would certainly have failed the last 3 MOT's on smoke emissions had it not been for a 'friendly' tester. I have done all the usual items, new MAF (didn't real need it), upgraded PCV, cleaned out EGR & manifold, I/C hose all good new 'O' rings fitted, new air filter, fuel filter, replace stat & water pump (engine now runs correct temp). Not sure where to look next, as stated the car runs really well but given the focus now on diesel emissions I am thinking that my MOT man may not be able to be so 'friendly' in future so need to try and sort this. Maybe a T4 health check? Nothing showed up on remap at c96K. Any suggestions would be most welcome Thanks Tony __________________ 2003 Mk 1 Connie SE CDTi Auto Monogram Mirage 2/Sandstone Leather 511th CDTi out of 4744 produced 9th in Mirage 2 out of 17 produced Also 2004 Rover 25 SXi CVT, 1999 Megane Cabriolet and still missing my 800 Fastback.