Black smoke

[Gary84]

Hi. New to the site. Having issues with my 2009 insignia 2.0 cdti diesel. Recently there are plooms of black coming from the exhaust on acceleration. This can be lower or higher gear changes. The engine management came on and subsequently diagnosed as the sensor in the MAS so was unplugged. This stopped all smoking immediately. I purchased a new sensor and fitted it. The engine management went off but now back to plooms of black smoke again....... Any ideas?

[0011728]

Welcome to the forum Gary . You really need to get the error codes read to point you in the right direction but some info about black smoke - this is really just an imbalance in the air to fuel ratio - too much fuel to not enough air. This means either too much fuel is being added to the mix or there's not enough oxygen being supplied to burn the fuel. The black smoke is full of particulates that are basically large diesel particles that normally would be burned as fuel.

Most common causes of black smoke are faulty injectors, a faulty injector pump, a bad air filter (causing not enough oxygen to be supplied), a bad EGR valve (causing the valves to clog) or even a bad turbocharger.

I would first be checking if there is a split in the boost pipe - the large black pipe on the right hand side of the engine (if the 160bhp one) as this is a common problem. If it is the pipe this video will help for diagnosis and repair https://www.youtube.com/watch?v=5FXWemvfF4c

[ilunn]

Just wait until just past the group of cyclist that insist on filling all road up then boot it then .

[Gary84]

Thank you for the advice I will check this today. The car in going in for Mot next week so I won't be driving about too much. The only thing I find strange (bear in mind I know as much about cars as I do the surface of the moon), is why would taking the air flow sensor off stop the smoke but putting it back on makes it smoke again. If it was one of the other things causing the smoke would it not still continue to smoke even when the sensor is removed?, I really love these cars and it's for first time it's given me any issues.

[Gary84]

Haha it has already been done! Not on purpose but it did make me smile ,

[Alex421]

If you're unplugging maf sensor the car will go into default fuel and air delivery. Reduced performance.
As previously suggested you should get a code reader on.

As now with new mot legislation any smoke from a diesel is an instant fail

[Butt0ns]

If there's smoke out the back then there's no DPF

[RBH]

Black smoke - not decided.......
White smoke - new pope