Intake cleaning worth it?
 

I have been contemplating pulling my intake manifold and cleaning it since it appears the EGR system has always been operational until now. How difficult is the job on these cars?

I have owned a couple VW Passat TDI's and I pulled the intakes on those and was shocked at how "caked up" the intake was. I could barley get my pinky finger in some of the passages that originally were very large. The difference in power on the VW's was dramatic.

Is this something worth doing on this car? Or should I just leave it alone?

Also, is there someone that makes a block off kit for the intake and the exhaust EGR holes?

If I were going to replace leaky gaskets,yes why not.Surely a cleaner intake without using the egr,would flow air better.

The Mercedes motors don't gunk up to the extent that the TDIs do.

-Jason

I second that. The TDI's are really bad for intake clogging. The 123's don't have that issue. That's not to say there is nothing in the intake, but it's not going to look anything like the TDI's do after several years. I've seen a TDI manifold that you could put a pencil through the hole there was so much carbon buildup.

I pulled mine when rebuilding the injectors, engine was running pretty good, but yet you will find PLENTY of oily carbon deposits--so much so, that my local friendly automotive machine shop would not place it into his hot tank, he declared that the diesel by-products would contaminate the solution too much...so based upon your mileage, do it.
Fish a copper wire through and fasten scrap cotton rags -w- kerosene and pull it back through, like a old gun cleaning kit would have you do. You will need a lot of rags!

I've owned both tdis and MBs, and the EGR promotes atrocious buildup in each

Exhibit A

Exhibit B

Exhibit C

One of the Members said he used one of the Foaming Oven Cleaners to clean out the gunk (Manifold off of the Engine of course). If you search there should not be too many posts/threads with the words Oven Cleaner in them.

Question?
On a 123; if you pull off the EGR is there enough room to put a Mirror down the hole and get a good look at the inside of part of the Intake Manifold?

Seems to me that when I removed my EGR valve (for testing purposes only), I was able to look in and also to do a little cleaning. It was pretty gunked up right in the area of the EGR but not so bad further in.

The intake on the OM606 engine in my '96 E300D was badly clogged; not as bad as some of the descriptions here but bad enough. With the EGR no longer functional, the pipes now stay clean except for a little oil film from the turbo.

Ditto for the OM603 engine in my '87 300D Turbo.

Jeremy

Thanks everyone. Thats enough for me... It's coming off.

Exhibit C tells the story. How many miles are on that engine?

Is this a difficult job on the MB? Assuming the gasket cannot be re-used like on the TDI?

Thanks,

AJ

My 85 was just like that when I upgraded to Federal (for testing) for a long term study on the effects of deep breathing vs stuffy sinus conjection.:D.

Mine was over 200000 miles and was really ginked up. About everyone I see at PNP have been the same. I like things clean, If the german engineers wanted it gunked up, they would have instaled gunk from the factory:rolleyes:.

Charlie

See post #1 in this thread for pictures of what my '96 E300D (OM606) was like at 251,000 miles. The PO had malfunctioning flaps replaced by the dealer but I doubt that any cleaning was ever done.

Snook You ever do this?
 

I know this is old, but snookwhaler, you ever clean the inake? How bad was it?

Yes...

It was just like the pics above A-C...

The result was less smoke and better throttle response. It had never been off before.

was it difficult to remove? what about parts? just a gasket?

oh, WOW! dude i am so glad i got rid of that crap and that cali doesn't smog diesel cars. heh