secondary air blockage
 

1998 ML320 264k mi. Is there any way to clear the secondary air ports without lifting the cylinder heads? po410 code,fan works,valves clear,rt side has airflow, left side blocked Thanks...Fred

air diverter valve cleaning
 

I just did this over the weekend on my 98 ML 320 w/ 256k miles. I needed to get my emissions inspection and the 410 code had been there for a while. The pic in this link are of the left side valve, which was completely blocked. There's a single bolt at the bottom of the post that you need to remove then pull the assembly out of the head. I had to rotate it +/- a few degrees to loosen the stub before pulling it out. The post was solid with build-up and the port in the head was solid. I just held a shop vac nozzle over the port and picked at it with a sharp tool to loosen the build-up. At some point, larger chunks came out and the shop vac got it all.

http://picasaweb.google.com/ahosmer/...eat=directlink

Good Luck!

I have the same problem with my ML. Mine is clogged on the driver side, and I can not see the blockage. Is there a way to clean it by removing the exhaust header?

I have the same exact problem with my w203, the driver side is completely blocked! Has anyone found a way to clear the blockage without removing the head?

Thanks

If this is about a C240, then you are on the wrong forum.

https://mbworld.org/forums/c-class-w203-3/