Smoke when i accelerate

[frankaai]

there is loads of smoke when i accelerate in each gear, i notice it more at night when someones headlights are shining behind me, but i can notice it during the day as well, could this be egr valve? the engine vibrates quite often on idle as well, if i clean the egr valve the correct way would it help? or should i buy a replacement?

[AlexB]

Smoke visible at night is normal. Both the vibration and excessive smoke under high load can be caused by the EGR valve stuck open. So, clean it anyway. Don't forget to clean the passages to the valve seat, then separate the valve from its solenoid and clean the area where they meet.

EGR problems are often related to bad oil and long drain intervals. Use only synthetic oil with MB229.5 or RN0710 on the label and OEM filters.

Another frequent cause of vibration is the top engine mount. There should be virtually no gap between the rubber and the top of the bracket. Just look at it.

If the smoke is visible at day time, then check the turbo. Lack of boost causes black smoke, the failing turbo causes blue-grey smoke. The latter is bad.

[frankaai]

thanks, the turbo seems to be pulling ok, im going to get a mechanic to clean the egr valve later as i need to get my electric window sorted and headlight... love these cars... lol i did clean the egr valve myself in my dads part washer but im assuming i didnt clean it properly, if its not the egr valve il get someone to take a look at the turbo, i also cleaned out the pipe which holds the dipstick, that was clean before but i cleaned it anyway, i also checked the pipes coming from the side of the rocker cover, could the intercooler pipes be clogged as well maybe?

[AlexB]

Let's continue in this thread, as its title seems more appropriate.

As the smoke is only seen at night in the headlights of a car following you, it's normal.

There is no way I can tell whether you cleaned the valve and everything else well or not. Probably well. It's up to you to decide. I would imagine the valve was moving freely and the solenoid was not dipped in solvent.

If the EGR system is clean, then the quality of oil is irrelevant, at least for half a year. Trade supplied 5w40 is mineral hydrocracked, it's the one which causes trouble with EGR in long term. Having said this, I observed recently a significant reduction in vibrations in my wife's car with the same engine after I changed oil from PAO to ester based. Don't ask me how it was possible. All I know esters are actually solvents, which clean everything while providing excellent boundary lubrication.

The engine mounts. The one which causes trouble is on top. Don't rely on the mechanics, have a look yourself. Make sure that everything around it is assembled and torqued correctly.

[taffyhl]

Under hard acceleration my 1.9dci lets out a puff of grey smoke but none otherwise. Likewise I have shakey idling after a long motorway journey but not if after short trips in town.

I suspect the EGR and will use the 'string trick' to test it. Plan is to detach the EGR solenoid and ues string to hang this from a suitable point. I will need to clean the EGR thoroughly first to make sure it is closing fully. Easy enough to do if it ever stops raining for long enough!