RS5 Strange Intake Valves!

A5/S5/RS5
#1

Started the valve cleaning process today. Pretty awful amount of work just to get to the valves…Anyways, I got the upper manifold off and was greeted with some strange sights…cylinders 1 and 6 have yellow flaps and the intake runners are brass colored, kinda oily. All other cylinders are blacked out. Pictures below show what I’m seeing.

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I’ll get the lower manifold off tomorrow for the closer look. Engine has 53k on it. Runs like a champ besides that one weird transmission issue last week. Barely burns a quart every 5k and I drive it every day like I stole it.

#2

First pic looks like somebody had the manifold off before and had some kind of tape blocking one side of the port on the intake flap. They may have still actuated properly but I’m surprised whatever it is, tape of some sort?, that it didn’t get sucked into the engine. Possibly they all had it and soe got sucked in or are wedged somewhere in the intake manifold (you probably want to use and inspection camera and look inside your manifold. You need to remove the lower portion of the intake manifold to do Carbon cleaning and you can pull the separator plates out. Make sure you install them the correct way and you need to hold open the diverter flaps at the actuator when you re-install otherwise they will get wedged against the plates on not open/close correctly.

#3

I simply ran out of time tonight. You know I was thinking that the car had never been valve cleaned because I saw no signs of anything being removed before. But now I don’t think so. Why would it have 2 yellow flappers? And why would those cylinders alone be so shiny? I’ve had the car for 20k miles.

#4

It’s like they did two cylinders and stopped! Kind of crazy but you can clearly see the valves are clean vs. the other where the flap is covered in oil. Very, very strange.

#5

Alright folks I’ve got a photo of what 1/6 look like and then all the rest are classic carbon black. What the heck is this about? Valve seals? Timing? PCV? Again, the car doesn’t use even a quart every 5000.

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#6

Local shop thinks valve seals are toast. I’m inclined to agree as the upper intake looks fine. What are my options? Sell it? Dish out for the repair which I’m guessing is $5k? Aftermarket warranty and wait for it to die?

Shop said $7k total. I’d rather get a fidelity or or Audi warranty and wait for the engine to die. Has anyone here any experience getting a new engine while having a tune?

#7

Are they planning on pulling the heads to do the seals? I’d get a second opinion. Especially if it isn’t using oil. Valve seals can be done by pressurizing the cylinder with a constant flow of air and then removing the valve springs. A good shop can do it this way, a shop that can not is going to charge you an arm and a leg for removing the heads. I do have a set of 26.5k mile heads??

#8

The guy said yes they would pull the heads. So basically an engine out procedure.

#9
#10

I actually watched this exact video earlier today and another guy working on a 5 valve 4.2. It’s much simpler than I thought. Lock timing in place, remove cam, pressurize cylinder, compress spring, remove retainers, and gently as hell replace the seals. Hopefully there’s a shop around that can do this. Got to it it back together first.

Is it possible to release the chain tension on the cam adjusters without having to remove the main timing cover and therefore the engine?

#11

That’s a good point about the adjusters. I’m out of town for a week but I’ll take a look on the 26k engine with the spun rod bearing when I get home. It’s just sitting on an engine stand. Mark

1 Like
#12

I’m almost done putting the car back together but I can’t figure out why I’m getting intake flaps bank 1 electrical malfunction. The wires looks fine and the flaps do not catch on anything. The sensor is good because I get a different code when I unplug it. When I search this code I only gets hits for the early S5 4.2. Any ideas?

I swapped the sensors and it’s still bank 1. I was checking advanced measuring valves and I pulled up 4 blocks called intake runner control. They seemed to be a pair and 1 pair was measuring 0v and another roughly 3.4v. Can someone else check what these valves should be? I may have a break in the wires somewhere but it may take time to figure out where.

#13

Must be a connector in the front connected to the vacuum controlling the flaps that isn’t snugged on? But you already figured that out. Checked VCDS , all I found was:

IDE00401 Intake manifold Runner Control (IMRC): acknowledgment 0.769 %
IDE00403 Intake manifold runner control 2: acknowledgment 0.574 %
IDE01369 Intake manifold runner control (IMRC): offset closed 0.840 V
IDE01371 Intake manifold runner control (IMRC) 2: offset closed 3.984 V

#14

Yep I tried that. If I actually unplug it I get a second code specific to the sensor

#15

My cylinder 1 and 4 had a lot less carbon than the others when I checked two years ago, that is just how the PCVs direct fumes unevenly, if not my car is screwed on 1 and 4 cylinders.

#16

spray them with electrics/ connector spray

#17

I had a lot more errors when I had a hose and or connector out at start.

Ignoring the tape or what the h£ll that is, Am I just stupid, or what are the odds of six cylinders all having bad valves.

I think the front valves are less likely to get as much of the exhaust via the PCVs, but the build up and other things will affect a bit where it goes.

If you really need a swap my neighbour has a new S6, not sure if you get it in the US as station car sounds like a V8

#18

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My valves. I was concerned about the 0%. I’ll see if I can’t manipulate these valves with a vacuum pump later.

#19

You can see the bottom three pictures have less carbon (I think two of the save cylinder). Should be fairly plain to see if leaking down on the valve. I had carbon there but I think that is because oil coming from the PCV sticks there (it gets less hot as well)

#20

I’d be shocked if starting the car to see (if it goes away) would damage the engine. Like I said, I started it with everything in a mess to check all the systems work.