Dannyboy201062
Senior Member
Hi All, I recently bought a minter C270 CDI, approx 120,000 miles. It surprisingly failed the emissions test on the NCT ( Irish MOT ) . "Smoke" reading was 3.750 / m.....the limit is 3.00/m @ 81 deg. oil temp. . This is the only item tested on emissions in the NCT. It drives very smoothly and seems to have been serviced well and recently. The only anomalies, are you do get smoke when you accelerate hard ( See it in the lights in the mirror at night ) , I considered it normal for a diesel. , it does idle a little erratically, it does seem to run cool , ie..takes forever to get up to 80 Deg ( or whatever half way up the gauge is ) .....runs at about 40 deg for quite a while. Fuel consumption is fine ....39 mpg tipping around ( 6 miles journeys rural ) and 46mpg on a longer run ( motorway 50 miles ) I had actually dosed the full tank twice , prior to the NCT, with a known good additive for improving emissions ( Dipthane ) . I`ve had a few diesels ( VW, Citroen, Peugeot ) but none have failed emissions.
Reading the forum, not much info on diesels failing emissions.....my plan is as follows:
1) Change the engine oil ,air and oil filter and stat. .( Going to do it anyway )
2) Read the fault codes ( No eng management light issues ) change the
lambda sensor if any codes for that.
3) Clean the MAF using a good carb cleaner. ( Spraying while removed )
3) Give it a good thrashing ( within rev limit ) by holding second gear while
dosing with more diaphtane. Hopefully the smoke in the mirror will
have reduced ........return for retest.
Any advice welcome......I haven`t dealt with this problem before. Presumably if the injectors were an issue it would not run as sweet as it does ( except for idle ) and fuel consumption would be poor. It does put a puff of smoke out on cold start ( starts instantly ) but I considered that normal for a diesel. There is an occasional electronic clicking sound sometimes on start up and for a short while afterwards which I put down to a glow plug system glitch.
Any Diesel merc experts out there ?
Thanks in advance........Dannyboy.
Reading the forum, not much info on diesels failing emissions.....my plan is as follows:
1) Change the engine oil ,air and oil filter and stat. .( Going to do it anyway )
2) Read the fault codes ( No eng management light issues ) change the
lambda sensor if any codes for that.
3) Clean the MAF using a good carb cleaner. ( Spraying while removed )
3) Give it a good thrashing ( within rev limit ) by holding second gear while
dosing with more diaphtane. Hopefully the smoke in the mirror will
have reduced ........return for retest.
Any advice welcome......I haven`t dealt with this problem before. Presumably if the injectors were an issue it would not run as sweet as it does ( except for idle ) and fuel consumption would be poor. It does put a puff of smoke out on cold start ( starts instantly ) but I considered that normal for a diesel. There is an occasional electronic clicking sound sometimes on start up and for a short while afterwards which I put down to a glow plug system glitch.
Any Diesel merc experts out there ?
Thanks in advance........Dannyboy.