Can you visually inspect head valves for carbon deposits?

[ReflexRob]

I've an 05 AXX GTi with 55k on the clock and lumpy idle.

The EGR valve and gasket was changed (but not check valve pipe at rear yet) which made no difference.
The cam follower has been changed but wasn't in a bad way anyway and the cam is not scored.

I don't really want to strip loads of stuff apart to see if there is any carbon deposits that need cleaning if I can get a peek at one or more valves.......

If anyone can help it would be greatly appreciated - this plus the cam chain tensioner rattle is really spoiling my ownership experience at the moment!

Cheers

Rob

[r5gtt]

all our gti tfsi engines will have carbon build up tbh with you and from all the reading up I've been doing on lumpy idle.

[dronners]

If you can get a boroscope into the inlet manifold thats one way To have a look

[ReflexRob]

Cheers chaps

I appreciate they will all have carbon but I suspect the idle will be lumpy when the build up gets really bad. The idle could also be something like vacuum lines though and I don't want to start chasing money around if I can avoid it by getting it right first time.

I do have a boreoscope so I will try that thanks - where is a good insertion point?

Cheers

[Dan_FR]

Only access is through the hole for the IAT sensor if the camera is small enough

[r5gtt]

Only access is through the hole for the IAT sensor if the camera is small enough

Did you manage to buy another boroscipe Dan?

[Dan_FR]

I've not got round to it yet

Another way in could be through the PCV connection on the right hand side, but then you're at 90 degrees to the valves which makes it a little more tricky

[r5gtt]

I've not got round to it yet

Another way in could be through the PCV connection on the right hand side, but then you're at 90 degrees to the valves which makes it a little more tricky

I'm. going to what the guys at my new workplace have if and when I get there. Hoping 15th February.

[FJ1000]

Have a look at 4:34 of this vid I made. I got in through the IAT sensor hole, and used a cheap borescope from Amazon that connects to your android phone/tablet.

Sent from my iPhone using Tapatalk

[grey golfster]

Only access is through the hole for the IAT sensor if the camera is small enough

Having wasted my time/money on a sump drop to change the oil pickup (a kind of good news I guess?) I'm planning to boroscope my inlets before dismantling to clean, if possible!
Please, where is the IAT sensor?

[Dan_FR]

Definitely good news and worth doing for peace of mind!

IAT sensor is right in the middle/top of the plastic inlet manifold, closest sensor to the middle/front of the inlet manifold when stood in front of the car. Single torx bit holding it in.

[ROH ECHT]

Cheapest way to inspect the intake valves is a bore-scope.
My valves and guides looked like this prior to cleaning:


Like this after cleaning with 1 part spirits to 4 parts petrol doing my own blow-by method through the IAT sensor on the intake mani:


The best results come from a media blast or manual scraping...but you can see the majority of deposits fell off with the blow-by.

This vid I made shows your access for the bore-scope...but disregard the audio description of the ratio of the solution, should one choose to clean this way, as I find it better to use 1-part spirits to 4-parts petrol.

[grey golfster]

Thanks for that.
I see your location as Pacific NW. US/Canada? A fantastic part of the world- I worked for Canadian Pacific years ago...
So I guess you have to run some sort of Cat then?

Great idea, and thanx for the vid...but where does all the sh1t go? I was hoping to see some vid of your exhaust outlet!!!

I am concerned as to what damage a solvent wash might do to my 3" Miltek sparts cat (bloody expensive!). Anyone got any thoughts on this? Normally, I would worry about missfires, or a tow/bump start putting contaminating matrix by putting large quantities of unburnt fuel thru...

Q. Is your mineral spirit what we in UK would call white spirit, also known as turpentine substitute?
I think we would have problems getting hold of  Naptha here too, but looks like your not currently using that?
How often do you do this?
Cat been tested for emmissions since?

[snowley]

That is a significant improvement visually!

[ROH ECHT]

Thanks for that.
I see your location as Pacific NW. US/Canada? A fantastic part of the world- I worked for Canadian Pacific years ago...
So I guess you have to run some sort of Cat then?

Great idea, and thanx for the vid...but where does all the sh1t go? I was hoping to see some vid of your exhaust outlet!!!

I am concerned as to what damage a solvent wash might do to my 3" Miltek sparts cat (bloody expensive!). Anyone got any thoughts on this? Normally, I would worry about missfires, or a tow/bump start putting contaminating matrix by putting large quantities of unburnt fuel thru...

Q. Is your mineral spirit what we in UK would call white spirit, also known as turpentine substitute?
I think we would have problems getting hold of  Naptha here too, but looks like your not currently using that?
How often do you do this?
Cat been tested for emmissions since?

I'm catless, but just done so recently, and there is no emission testing for our area. Had a 400cell cat before when I first started doing this. No, nothing was wrong with the cat requiring removal...I just removed it because "race fuel" that is leaded is half the cost of unleaded.

It's carbon and should pass just as it would when it eventually falls from the valve stems naturally. Additionally, the catalyst can heat up to 1200°F and is designed to burn pollutants. White spirits is same as mineral spirits.

I found the cleaning is not needed often if engine is tight...obviously, build-up will develop more often if valve stem guides are worn or if more is recycled through the intake air.

I think I first needed to do this, checking with the bore-scope, at about 70k miles. If you see build-up returning often...then it's likely time to address the cause rather than the effect.

Here's a vid of the Fleming Product; BG44K injection cleaning...I looked up their MSDS and found the product is roughly 25% spirits and 75% fuel(petrol).

...this shop states that some is added to the fuel tank, but we know that does nothing for our valves...on direct injected systems it only works for cleaning injectors.