Secondary air injection

[uprightbrian]

Hello all.This is my first post.
I have a fault on a CLK 230 kompressor. The scan tool came up with secondary air injection fault. I have been told that it may be the solenoid valve that is at fault.
Any sujestions would be welcome. Many thanks in anticipation. Brian

 

[Ultymate]

Brian hello and welcome you don't say what year your 230k is but I think on them all the supercharger is used on cold start to feed extra air to the motor to aid the quicker warm up of the catalytic coverter I believe the valve that achieves this on my car which is a 98 model is attached to the air cleaner and is item 86 in the schematic in this link http://www.detali.ru/cat/oem_mb2.as...GM=717.460&CT=M&cat=19K&SID=09&SGR=015&SGN=01 Hope this helps

 

[uprightbrian]

Many thanks for the info. I will have a look at the weekend when I have more time. Regards Brian.

 

[type49]

Near the very back of the cylinder head there is an air pipe that comes up from a valve connected to a hollow tube which is about 1.25" diameter. The valve is a flame trap held on by a 22mm spanner size. It is a bitch to undo! Ideally you need a 22mm open ended spanner and then bend it 90 degrees to gain access to the nut which is part of the valve. The valve should allow air through one way and not the other but when they fail, air can be passed in both directions causing a secondary air fault. If you mange to undo it, it won't cost you anything to see if you can blow both ways. If it's OK, you should be able to blow through one way (with a bit of a restriction) and not get any air through the other way. The valve is fairly cheap to buy.