To clean or replace lower manifold on 1.6FSI

Good evening chaps - Well after the second fuel injector failure on my wife's FSI, I have the lower inlet manifold off, which was cleaned and the actuator replaced by A2Cars 5 years ago.

Really simple question: should I replace the lower manifold or just get it professionally cleaned?

All thoughts welcome please...

I suspect that the poor running caused by the failed injector hasnt done much for the carbon build-up.
 
The manifold is well before the injectors, let alone the valves and combustion chambers etc. The crud that builds up in the manifold and around the flaps is mostly from the EGR and PCV circuits. More exhaust particulate and oil condensate residue. This is my theory anyway. If I'm on the right lines, using top quality, detergent rich, clean burning 98 /99 octane fuel, and fully synthetic oil, that is actually certified to the VAG Spec (rather than the meets VAG Spec, which is not the same thing), will minimise future crud.
So, my advice is to clean yours, and go forward with a scrupulous fuel and oil (change, along with the filter every year). regime.
Good luck.
Mac.
 
Good evening chaps - Well after the second fuel injector failure on my wife's FSI, I have the lower inlet manifold off, which was cleaned and the actuator replaced by A2Cars 5 years ago.

Really simple question: should I replace the lower manifold or just get it professionally cleaned?

All thoughts welcome please...

I suspect that the poor running caused by the failed injector hasnt done much for the carbon build-up.
A new manifold is getting on for £500!!!!!

Cleaning either by you or professionally is much cheaper!!!!

Andy
 
Thanks very much gents - I will start looking around for professional cleaners - any steers as to what types of businesses do this please?
 
And if you want to prevent having to do it in the future, have a look at the Pro Boost remap.
 
The manifold needs to be clean, so the flaps move freely. Doesn't have to be super shiny, gas flowed or anything. What used to be called motor engineers (or even a garage) will be able to help. Needs a solvent cleaning bath, to be done safely.
I'm sure someone on here has done it. Luckily for me, so far (52, 000 miles, all on 98/99), I haven't needed to.
Mac.
 
Thanks Mac - I'm going to try this lot: they're nice and close and seem to be the ticket.

 
Thanks Mac - I'm going to try this lot: they're nice and close and seem to be the ticket.

They sound like a good choice. Let us know how you get on. Wonder if they would allow a few pics of how the process is done? That would be great.
Mac.
 
Brake cleaner, steel wool, elbow grease, mask, gloves etc. The crud is not, directly, the problems, it's the the accumulated crud around the flaps and spindle that stops the flaps from moving correctly (and so triggering the EML via the flap potentiometer). The cleaning process must clear the area around the flaps and spindle, to ensure they move freely, and stay that way as long as possible (hence the fuel/oil regime) . It's not necessary to get the inside of the manifold squeeky clean (although doing so would be satisfying).
Given the health risk of solvent exposure, and nasty (carcinogens?) stuff in the crud, I'd leave it to the professionals.
Mac.
 
I will see if they can be clear about the process they use. I’m not sure if they’re going to let me be there whilst they do it to take pictures…

The reason I am not DIY (having completely DIY dismantled the engine so far) is because I reckon that part of the stiffness is soot getting into the spindles on which the flaps sit. Baking soda and a toothbrush is not going to touch that.


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That’s what they use : vapour with some media. I’m going to pick up at lunchtime, so will try to share some pictures later. In the meantime, does anybody have any experience of fitting the manifold flap actuator with the lower manifold in situ? There is a chance that the one I have ordered may not be delivered today…


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That’s what they use : vapour with some media. I’m going to pick up at lunchtime, so will try to share some pictures later. In the meantime, does anybody have any experience of fitting the manifold flap actuator with the lower manifold in situ? There is a chance that the one I have ordered may not be delivered today…


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Not first hand experience, but I know it looks possible. There is a small recess in the casting whose position suggests it was put in the casting for the removal/installation of the actuator with lower inlet manifold in situ. Look at what BiggDogg posted here.

Andy

Edit. Panic, don't do it, just remembered the manual dictates the actuator arm must be pinned raised using the holes in the arm during manifold installation or the adaptation will fail.
 
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Could be removed, along with associated bits, if a ProBoost map is fitted I'd think.
Maybe @A2Steve could ask ProBoost for their advice? (Once he's over BB's demise that is).
Mac.
 
Yes, it could be removed completely. I used the vacuum pipe that went into the actuator to feed my boost guage so the system wasn't even connected.
 
Could be removed, along with associated bits, if a ProBoost map is fitted I'd think.
Maybe @A2Steve could ask ProBoost for their advice? (Once he's over BB's demise that is).
Mac.
Yes, it could be removed completely. I used the vacuum pipe that went into the actuator to feed my boost guage so the system wasn't even connected.
My reservation is that a member recently reported who had a broken actuator arm that the flaps rattled like this. Not surprising since without the actuator there is nothing pinning the flaps open, except their own weight under gravity, therefore free to move, not surprising they rattled.

Andy
 
I was thinking flap and spindle removal for ProBoost, following on from the rattle report, then blanking the spindle pivots.
Not sure if that's doable though.
Mac.
 
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