hey guys, former chrysler dealer tech here with an 08 e350 4matic, fairly new to me. About two weeks ago cel light came on, p0171 and p0174, both banks lean. I found the maf had a broken tab, i cleaned it and the TB (did seem to give it a little more juice) and then ordered a new maf from fcpeuro but as i assumed this didnt fix it. Last week I got an intermittent high idle ~1000-1250rpm and a couple times when put in park would idle to 2k. Smoke machine arrived and I just smoked the intake today. Im getting smoke below the driver side intake flap actuator/oil filter housing area but without removing components cant see the precise location. Im fearful it is the manifold gasket but thought I would check in here to see if it may be something else down there, the hoses seem solid from what i can see. is it possible that the intake runner seal is bad? also if it does turn out to be the manifold gasket, is it recommended to replace the entire manifold? it has the aluminum updates for the actuators, though they appear slighly bent, is this normal? Thanks for any help. PS - yes i know my water outlet/ upper hose is seeping, I have the parts and will replace during this fix haha

 

There’s a number of vacuum lines in that area... the hard lines, often get brittle with age. You also have the solenoids and actuators.

That’s where I’d start before pulling the intake.

 

I finally got time to dive into this today, and the various other maintenance items I had planned. After I pulled the egr for better access to front of manifold here’s what I found



the longitudinal switch flap shaft is broken and the manifold has been worn through.

I have a new manifold on the way, I ran into a few old worn out parts while pulling sub systems;
- removing the overflow tube from the upper hose, the end of the tube disintegrated, then I pulled the tank end and the tank side connector disintegrated!
- passenger side cam sensor connectors lock tabs broke. I was extremely gentle prying the tab from bottom side, exhaust broke immediately and intake broke when I snapped it back on before I decided I wasn’t putting it all back together with rtv over the manifold hole.
-lower thermostat bolt came out pretty hard, looks over tightened, the first couple threads are stretched.
I’ve got a little ways to go for the rest of the manifold. Would like to get it back together ASAP as it is my typical daily, tho I have other options. I would like to take care of any vulnerable/ common issues now with the manifold out, anything I’m missing that I haven’t gotten to yet? Thanks!
Plan on doing some more pics when I go back together/ tear down the old intake for future references

 

Check all the parts in the breather kit, especially the breather cover and oil separator.

https://www.fcpeuro.com/products/mer...kit-oem-515810