I might need a carbon build up clean, what do you guys think?

[m0j0jojo]

Driving a 2012 GTI. Started noticing rough idle, car shakes a bit sometimes when im in neutral, and sometimes third gear the car starts to jerk almost as if its about to stall when I press the accelerator. The clutch feels fine though, its stock and it doesn't feel stiff, but sometimes it is hard to put it in gear. There are no error lights being shown.
But what do you guys think.

It has just over 128000 Km

 

[GolNat]

Could be. Get a cheap scope and take a look. It's super easy to inspect.

 

[Blakcard]

128? Take it to Mario at K&N. He's on St Clair. Decent price.

At that mileage I would get it done if you have not had it done before. Have you checked your plugs? When did you last change them?

 

[m0j0jojo]

128? Take it to Mario at K&N. He's on St Clair. Decent price.

At that mileage I would get it done if you have not had it done before. Have you checked your plugs? When did you last change them?

I changed them last year around this time. How much does he charge?

 

[Blakcard]

I honestly can't say as the last time I had it done was when he was replacing the water pump and it was $250. I think he charges under $600. It's a couple hours work. He does good work. Will take pics before and after. Probably best to just give him a call and ask.

 

[zrickety]

Hard to put into gear? You might need to adjust the linkage, or maybe some air in the clutch line.
Checking the plugs is not a bad idea, I've seen the gaps close up on 2 different cars for whatever reason.
Don't think you need a carbon clean either...30 min hard driving on back roads (3000+ rpm), Italian tune up.

 

[Blakcard]

How will the Italian Tune up get rid of carbon build up? I thought it was good for inbetween carbon cleaning to slow the onset of the build up?

 

[gijoewoz]

How will the Italian Tune up get rid of carbon build up? I thought it was good for inbetween carbon cleaning to slow the onset of the build up?

It won't. If there is enough carbon build up to cause the car to run badly driving it hard isn't going to do anything to help.

 

[zrickety]

I post about this all the time...my car has 170k miles (274,000 km) and has never been carbon cleaned. It runs great. You do the math.
Driving hard removes some of the build up. Not saying all of it. But I can't tell you how many times I see guys post about engine issues, get a clean, and the problem is still there. You would need some SERIOUS build up to cause an issue, that just doesn't happen at 128km = 80k miles. There is something else going on.

 

[dcpppf]

FWIW, I just cleaned my intake valves on my 2012 6spd this last fall at 50,000 miles. I felt absolutely nothing abnormal, but was getting intermittent misfire CELs (i forget which two cylinders) and the cleaning cured it. I agree w/ zrickety in that it doesn't just go from no signs at all to driving poorly over night. That, to me, is a big jump.

on a side note... I used to not drive hard hardly ever. But would cruise in 4th at 70-75 for half an hour once very few months as an "italian tuneup"... which obviously did nothing for me lol. If you drive hard damn near every day I have no doubts it'd help. But don't waste your time/fuel doing it as sporadically as I had!

 

[zrickety]

This is just an aside, but my wife's Honda Pilot would randomly misfire and go into limp mode...it was crazy. It wouldn't shift or go over a certain speed unless you disconnect the battery. Happened a few times until I found the cause- a dirty air filter. After I replaced it the misfires and limp mode went away! Something to consider.
Also, if you are on the original intake manifold, expect that to fail soon.

 

[Dans GTI]

Driving a 2012 GTI. Started noticing rough idle, car shakes a bit sometimes when im in neutral, and sometimes third gear the car starts to jerk almost as if its about to stall when I press the accelerator. The clutch feels fine though, its stock and it doesn't feel stiff, but sometimes it is hard to put it in gear. There are no error lights being shown.
But what do you guys think.

It has just over 128000 Km

You only have 80k miles. You have another issue at play here, its not due to carbon build up. You should get the car diagnosed.

 

[funkymcbain]

You should be getting CELs but that sounds more like a failing ignition coil. Having said that, get it cleaned anyway, I did mine at about 150km and it was pretty nasty in there.

 

[Grabbit]

I did my first de-carb at about 78k miles and I never had any CELs or codes. Valves were pretty gunked up and afterward I definitely felt more power, especially down low. I would do it and replace the PCV valve with the latest OEM revision or consider running a catch can.

As someone else said, its pretty easy to get a cheap borescope that connects to your phone and check the top of the valves through the spark plug hole or by taking the intake air temp sensor out (one bolt). This is located on the front of the intake manifold just after the throttle body.

 

[m0j0jojo]

128? Take it to Mario at K&N. He's on St Clair. Decent price.

At that mileage I would get it done if you have not had it done before. Have you checked your plugs? When did you last change them?

Do you know if AST tuning, does carbon cleaning? They are much closer to my home thats why im asking