cleaning secondary air 99 S5 - PeachParts Mercedes-Benz Forum

MBD · #1 07-08-2009, 11:43 AM

I had the test run on my Benz W140 (223K miles) last week before leaving on a 2K mile trip. As I have stated before CEl code PO410 only shows up at cold start once the engine goes thru self check. If I race the engine slightly during the check I get no CEl. The Benz Tech told me I have a slight carbon build up on the right side(passenger side) of the engine. The drivers side is open with no problem or detectable build up. Is there anything I can run through the ports which will semi clean to clear it enough to prevent the CEL? If there is can it be done by running it through the pump vaccuum or is there another place? Thanks for the reply I am trying to do this without having to pull off the top of the engine. All the best, MBD

MBD · #2 07-09-2009, 03:32 PM

bump

MBD · #3 07-11-2009, 09:43 AM

Has anyone been able to semi clean the ports in any way except opening the top of the engine. I am just wanting to stop the irritating CEL from coming on.

samdon · #4 07-13-2009, 10:53 AM

MBD,

I too am waiting anxiously for an answer to your question. Quite a while back, Mr. Hunter or M.B Doc, I believe it was, offered a bit of info on the possibility of performing a chemical clean on the secondary air passages stating that various mixes available at the local autozoo could do the trick. I was never able to find a prodedure for doing the deed, though.

It seems as if it should be fairly simple but I am very cautious with such things. Maybe wHunter and/or M.B Doc will ride in on a white horse and help us out here.

MBD · #5 07-21-2009, 09:26 AM

anyone?

mbdoc · #6 07-21-2009, 09:31 AM

Since the passages are blocked by carbon and hardened by heat, I have never been able to use any chemical to re-open those passages.

Every time that happens the cylinder head(s) have to be removed & passages "drilled" out.

MBD · #7 07-29-2009, 06:21 PM

Thanks Doc. If the blockage is not complete but almost is there a fluid to run through it that may help? I have heard back some while ago that someone had run a cable after soaking it with some commercial carbon cleaner and it helped. Have you heard of such a thing? Thanks! MBD

mbdoc · #8 07-30-2009, 08:14 AM

The ports are under each of the 16 exhaust valves & can't be reached.

Have heard of a product that Dodge dealers sell... never had any luck with that type of "stuff".