M-Class (W163) 1998-2005: ML 230, ML 320, ML 350, ML 400 CDI, ML 430, ML 500, ML 270 CDI

secondary air blockage

Old 01-18-2011, 10:07 AM
Thread Starter
Join Date: Jan 2011
Posts: 3
Likes: 0
Received 0 Likes on 0 Posts
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
Fred Hayes is offline  
Old 01-20-2011, 05:10 PM
Join Date: Nov 2010
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
98 ML320, 00 ML430, 02 C240
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.

Good Luck!
ahosmer is offline  
Old 01-28-2011, 11:49 PM
Join Date: Aug 2010
Posts: 6
Likes: 0
Received 0 Likes on 0 Posts
99 Ml320
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?
Wkjones is offline  
Old 03-27-2018, 09:13 PM
Join Date: Mar 2018
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
2004 c240
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?

Jeremy Medinac is offline  
Old 03-28-2018, 05:17 PM
MBWorld Fanatic!
Join Date: Oct 2011
Location: Westchester, N.Y.
Posts: 4,120
Received 347 Likes on 334 Posts
2002 ML 320 & 2006 ML500
If this is about a C240, then you are on the wrong forum.
Maj. Dundee is offline  

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

Thread Tools
Search this Thread
Rate This Thread
Rate This Thread:
You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: secondary air blockage

Contact Us - About Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to and affiliated sites.
  • Ask a Question
    Get answers from community experts
Question Title:
Your question will be posted in: