jho9393

So I just found out that my intake manifold needs to be replaced because the mechanic told me that the 3 rods kept on popping out. He said there is no way to just replace those rods and getting a new unit is the only option. Is it absolutely necessary to replace the intake manifold? my 06 has over 200k on it and I was planning on getting a new car sooner or later... Would not replacing it do my car any permanent damage? Thanks.

cetialpha5

There are several threads about repairing the intake manifold. I think there's one piece you can buy online for around $50 that fixes it so that those rods don't keep popping off. Or you can get a cheaper manifold online.

jho9393

Ok. Is there any way to replace that part without taking out the whole intake? I'm not necessarily a DIYer so not really confident in doing that.

cetialpha5

I think the whole manifold is around $1000-$1200 from an mb dealer, but people mention getting it for around $400+ on ebay. Otherwise I'd just buy that little part and have an independent mechanic do it. Try a different mechanic if the one you have won't do it. I believe the part is inside the manifold so it will need to be removed.

ushojh1

no room to replace just the rods & pivot without pulling the manifold. i just had to replace my intake 3 months ago. talked to an indie about just replacing the rods & pivot and he said they won't do it anymore. problem is the internal plastic flaps are getting gummed up and that is putting extra force on the rods to work the flaps. i installed a rebuilt intake in my '06 E350. manifold cost me $350. you can find new ones for $600. it's pretty easy to replace...just alot of wiring harnesses to undo and move out of the way.

PSDCampervan

I have a 2005 E320 CDI with 231K on odometer. While not identical to gas engines, it has similarities in intake manifold in that there is a servo motor-driven linkage assembly that operates swirl flaps to optimize fuel/air ratio entering cylinders.
The swivel link is a ball & socket design at both ends which eventually gall out & allow gravity to disconnect them from linkage & fall into engine compartment undercover. This happened to mine resulting in a wandering idle on cold starts & decreased fuel mileage. After pondering what to do, I finally came up with drilling holes through both ends of link bar & their coresponding swivel arms so that they will all line up with link bar in place. I threaded a steel diamond wire like you'd find on a sailboat mast shroud first through swivel arms & then through link bar where I tied wire ends into self-tightening knots like a Chinese finger trap. I then pulled link bar into place & did the tighten-up by twisting wires together with needle-nosed vice grips. It has worked well so far. Cold starts are smooth & fuel mileage restored. I might eventually crimp wires right at swivel arms to eliminate extra wire in future if this hack holds up. Linkage has been restored with full range of motion!
There isn't much room to work in there, I had to use a 12" drill bit extension, long needle nosed pliers, & a flashlight to fish those wires through. Many hours of fun but ends justifies the means as intake remained in place through whole process & no other parts had to be removed.

Azeem

PSDCampervan,

Thanks for the input. I have a similar issue on my e270 cdi with flaps gunked up resulting in oil loss. I haven't noticed any performance issues and mileage is good but it leaks oil from those flaps for sure.

Could you please send some clear pictures of your manifold for understanding? Secondly, did you take out the manifold yourself for this job or can this be done without taking out the whole thing?

Thanks

PSDCampervan

Picture this inverted as that is how it will look in your car, that angled piece is the pivot link bar. One side connects to servo-motor swivel arm & other side connects to swirl flap common rail swivel arm. In position pictured, servo motor is holding swirl flaps open. If disconnected, air flow will preferentially push swirl flaps closed. I drilled straight through connection at both ends & this is where I threaded wire through. I didn't have to remove anything except plastic bonnet (which I leave off anyway so I can regularly inspect all components). The picture in my previous post is of how it looks in my car, looking down through gap between #3 & #4 cylinder intake you can see m55 pierburg servo motor's swivel arm w/ wire running through to attached link bar. That gap space between 3 & 4 is where all work was done. That wire is what keeps those two together as ball & socket connection is too galled away to keep link bar in place independently under load. The same is done on other end as well. Twisting the wire on itself tightened it up so that both ball & socket joints stay mated under pivotal load. The leakage you're observing on yours is most likely partially burned fuel that has crusted up & transformed itself into coal like substance from EGR. There shouldn't be any oil circulating there at all.

ptkacik

Wow. Thanks for the write up. My '05 CDI is around 165,000 miles and running fine; however, I'm expecting this to fail sooner or later.

It seems like the wire will eventually give up and then a manifold replacement is in the cards.

I used to moan about the manifold and EGR problems but I really haven't done anything serious since a new EGR at 50,000 miles so I'm okay even when the manifold needs changing.

I replaced a differential seal yesterday and will say these are not trivial jobs but not impossible either. With guidance, anybody could do them. Torquing some of the fasteners can be tricky though.

Peter

ptkacik

Correction, I have worked on it in the last 100,000 miles. I replaced the diff seal.

But otherwise, it's been trouble free for 100,000 miles.

Peter

imp_biz_kit

Has anyone ever bypassed this swirl flap system? Like, disconnect the actuators and pin the flaps in the full open position? Or, better yet, open up the manifold and remove the swirl flap contraption entirely? I thought I ran across an article or video where someone recommended getting a used European version of the manifold that doesn't have the swirl flap setup. Is there such a thing?
Thanks,
Bryan

cetialpha5

They're basically tuned intake runners. It's at one setting for high rpms and another setting when it's at low rpms so ripping them out means it will run badly at one of those settings. That's basically why you need it fixed because it runs badly at certain rpms when the flaps don't move. Eventually the flaps may break off and fall into the engine causing damage so it should be fixed with a new intake unless you're not going to keep the car long and just want to replace the broken parts.

imp_biz_kit

Yeah, I understand what their purpose is, I just don't like expensive fixes for poor designs. The P/O told me that they had to replace the intake. I don't have any receipt for it so I'm taking him at his word. I'm just trying to plan ahead, in case I have to deal with it.
As a preventative measure, I wonder if running SeaFoam through the intake can alleviate some of the carbon buildup that might be partially to blame for the breakdown? I imagine it may make it worse, adding another chemical to to equation to mess with the plastic flaps...

cetialpha5

It should last 100-150k so if it was already replaced should last a bit longer. There really is no replacement for the design. You'd have to go to the M276 engine which was 2012+ E350's to get away from the intake problem.

As for seafoam, not sure about that, no one else has done it. Could be very dangerous. You go first.

imp_biz_kit

Ha! I'll just hide over here and wait to see if someone else does it....

ptkacik

BTW, my '05 CDI is now past 220,000 miles and still no problems with the swirl flaps. Knock on wood but maybe it's not the worst design.

However, the front ball joints are now squeaking so I've decided to replace the lower control arms (all four).

Good luck,
Peter