vacuum leak update
 

just-n-time here,I got into the fuel tank filter today,it looked good,some trash but just enough to say it is doing its job.(see pic)
Intake is another story,it is a mess,the air duct housing was not properly seated to the intake must have leaked.
Varnish is abundant in the air duct,and nasty looking in the lower intake too.
I will keep every one informed as I go thru the system j-n-t:behead:

Dude, you must be really bored...

Great job. I hope to never have to do that.

bored who me?
 

Not even in the least! I just like things to work,If I cant go out and turn the key and go then I must know the reason why.Perhaps It will be for my own edification,or some thing to pass along.Besides I have to do something in my early retirement,j-n-t:behead:

Ok, I am going to admit my ignorance in the interest of learning something :) So those pictures are of the ducting from the airbox to the throttle body and they are coated in oil because there was a vaccum leak in the ducting that killed the vacuum which allowed oil from the EGR or something to enter back into the system due to a lack of vacuum? If true, did it kill your MAF? What model of car is this, please?

Thanks!

oil,No
 

First this is a 1990 420sel,The trash you are looking at is varnish,and soot from a very rich condition.I split the intake today and have more pics for all to see. The first shows soot,The second is badly varnished,third is cleaned The last is another view of the soot. all the o-rings are hard:behead:

product of years in storage
 

By the way I realize you haven't read the other sights in my name so just in case others have the same problem,I should say this car sat for a very long period and varnish got to it,It was repaired but only skimmed over and so much else needed to be also addressed,sense I got the car I have tried to put it back in the shape it should be in,j-n-t:behead:

So where is all the varnish comming from? Varnish is whats left after the gasoline evaporates. There should not be any fuel in that part of the intake system. I suspect that the fuel distributor must be leaking fuel into that area. If so then it might need to be replaced.

What are your thoughts on this?

make sure you replace every rubber part on and in this intake.including injector seals and cups and o rings.all the air tubes including the one going under the fuel injection plenum.you will be very pleasantly surprised when all back together.

David, If I call you-- Could you answer a couple questions I have about my 88 420 SEL?


Sorry to hijack the post-

Carry on-

fuel distributor
 

This is one part I know was replaced or rebuilt by the service department at my MB shop,just before I got the car I have had it for 10 months,and we only have put 250 miles on it,and have had a great deal of work to do in order to get it back up to snuff. though when I removed the intake it was wet in there I thought it might be from me trying to start it! Not real shure.j-n-t:silly

Hi Dave
 

Yes my Friend,I have all new donuts,inj.seals but I did not order cups or o-rings,I will call Phill friday morn. what do you think about the wet in side the chamber? think the fuel dist.block might still have a leek? It was very wet deep at the throttle body chamber. Well one step at a time, rather take baby steps till it is done. j-n-t:behead:

When I did mine, I found the EGR pipe blocked with soot at the intake manifold. Also, the pipe on the bottom of the air cleaner tha mates up with the hose to the back of the passenger sode valve cover was also blocked. Don't forget the clean the small orifice in the idle air bypass area and cold start injector. I had to use my trouble light probe, with a really sharp point, to push out the gunk.

Check the groove on the heads under the intake ports for carbon deposits.

I used a media blaster to clean my intake manifold both inside and out. It looks really great now, at least the parts that I can see.

carbon
 

Yes I inspected all of that and it was farely clean, the trac at the bottom of the heads had some build up but not pluged.It is just so cool that this unit has so little of it for as old as it is. Thank you for the heads up j-n-t:behead:

up date
 

Well today I got every thing put back together and after holding my foot to the floor it Finlay lit off,though it idled at 4000 rpm.Apparently it was adjusted in the throttle linkage to compensate for the air leek at the air duct housing.
Worked on that and have it at 700 now but I am sure we will have to continue to fine tune the system,as it is rough right now will work on it more in a couple days or so and continue the update j-n-t:behead:

varnish
 

The only thing I can say about the varnish is that whom ever re installed the air duct housing and did not get it seated on to the throttle body,a gap was to much for the fine adjustments to solve so the option was to open the throttle body linkage there by increasing the amount of fuel to compensate for the added air,this caused an environment to be in a flood condition,perhaps I am wrong but it is the best I can come up with,j-n-t::idea2: