So I read this whole thread waiting for this suggestion. And YES, it does create a cloud of smoke until all the carbon is burnt off. But it does work.
6
Carbon Build-up at 26K Miles
- Thread starter haymest
- Start date
So I read this whole thread waiting for this suggestion. And YES, it does create a cloud of smoke until all the carbon is burnt off. But it does work.
excelevant
Go Kart Champion
ITU +1234567k rpm
DaveSTR
Go Kart Champion
Try search. Seafoam is useless. Nothing much of anything gets burnt off. So all of the carbon is there and you might fry coils and possibly hydro-lock your motor. Please do not use this useless substance.
McQueen77
Banned
According to the fine engineers at VW, the 'italian tune up' does work:
"An additional approach for reducing the formation of carbon deposits on the intake valves 20 is to increase the intake valve temperature, at least temporarily, since, surprisingly, it was found that any carbon deposits possibly present are removed at temperatures above 380° C. To this end, the intake valve unit, which comprises, among other components, the intake valves 20 and the valve stem guide 28, is designed with means that hinder heat dissipation in such a way that increased surface temperatures of more than 380° C. develop at least in the area of the neck 68 of the intake valves 20 in at least one predetermined region of the load characteristic diagram 74 of the internal combustion engine. This is illustrated in FIG. 4. The intake valve temperature is above 380° C. in the shaded region 112 b of the characteristic diagram. At these temperatures, carbon deposits on the intake valves 20 are removed. This region 112 b of the characteristic diagram occurs, for example, at speeds over 3,000 rpm, and in that speed range. extends essentially to full load. Even if the internal combustion engine is not operated most of the time in the region 112 b during normal driving operation of a motor vehicle, nevertheless, carbon deposits that could adversely affect the operation of the internal combustion engine cannot build up, since their removal in the shaded region 112 b of the characteristic diagram occurs very quickly. For example, operation of the internal combustion engine in this region 112 b of the characteristic diagram for a period of, for example, 20 min., is sufficient to remove even a thick layer of carbon deposits. In other words, a routine expressway trip cleans the intake valves 20 sufficiently. "
Source: Original D.I. patent by VW
http://www.google.com/patents/US6866031?printsec=description&dq=valve+coating+carbon+VW
Pretty much everything you want to know about this issue can be found there. Read it. Very enlightening. Safe to say Hanz and Franz know, like, WAY more about this issue than any of us. So if they say hard driving can burn off the carbon, I shall ride her hard. People saying hard driving and italian tuneups dont work for carbon buildup on these engines seem to be missing the whole point. It just seems too easy a solution to such a seemingly daunting problem. Straight from the horse's mouth.
So start driving the shit out of your car and if 90% of your driving is in stop and go traffic, the GTI isn't your problem and you should (a) take public transit (b) buy a $5k Civic to commute in or (c) kill yourself because 90% of your driving is in stop and go traffic at speeds of 10-20mph and you are wasting your life.
"An additional approach for reducing the formation of carbon deposits on the intake valves 20 is to increase the intake valve temperature, at least temporarily, since, surprisingly, it was found that any carbon deposits possibly present are removed at temperatures above 380° C. To this end, the intake valve unit, which comprises, among other components, the intake valves 20 and the valve stem guide 28, is designed with means that hinder heat dissipation in such a way that increased surface temperatures of more than 380° C. develop at least in the area of the neck 68 of the intake valves 20 in at least one predetermined region of the load characteristic diagram 74 of the internal combustion engine. This is illustrated in FIG. 4. The intake valve temperature is above 380° C. in the shaded region 112 b of the characteristic diagram. At these temperatures, carbon deposits on the intake valves 20 are removed. This region 112 b of the characteristic diagram occurs, for example, at speeds over 3,000 rpm, and in that speed range. extends essentially to full load. Even if the internal combustion engine is not operated most of the time in the region 112 b during normal driving operation of a motor vehicle, nevertheless, carbon deposits that could adversely affect the operation of the internal combustion engine cannot build up, since their removal in the shaded region 112 b of the characteristic diagram occurs very quickly. For example, operation of the internal combustion engine in this region 112 b of the characteristic diagram for a period of, for example, 20 min., is sufficient to remove even a thick layer of carbon deposits. In other words, a routine expressway trip cleans the intake valves 20 sufficiently. "
Source: Original D.I. patent by VW
http://www.google.com/patents/US6866031?printsec=description&dq=valve+coating+carbon+VW
Pretty much everything you want to know about this issue can be found there. Read it. Very enlightening. Safe to say Hanz and Franz know, like, WAY more about this issue than any of us. So if they say hard driving can burn off the carbon, I shall ride her hard. People saying hard driving and italian tuneups dont work for carbon buildup on these engines seem to be missing the whole point. It just seems too easy a solution to such a seemingly daunting problem. Straight from the horse's mouth.
So start driving the shit out of your car and if 90% of your driving is in stop and go traffic, the GTI isn't your problem and you should (a) take public transit (b) buy a $5k Civic to commute in or (c) kill yourself because 90% of your driving is in stop and go traffic at speeds of 10-20mph and you are wasting your life.
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Baldeagle
Ready to race!
I accept the premise that high heat can clear carbon from the upside of the valves. But how do you really get an engine that hot for 20 minutes? To cruise at 80 mph in our cars, our engine needs to produce a whopping 27-28 horsepower. Even though the rpm may be at 3,100-3,200 rpm, it's barely working and doesn’t produce those coveted BTUs. If we run in a lower gear for higher rpm, the higher rpm may shake the valves more but it will not produce significantly more heat. You'll still burn essentially the same amount of fuel to produce that 28 hp.
Long bursts of acceleration will undoubtedly get the engine hot. But aside from a race track, where can anyone realistically drive full-on/back-off over and over again ......for 20 minutes straight? It would be nice if we had an Autobahn where we could cruise at 120 mph for 40 miles, but we don’t. Sorry, but I can’t see any of us actually getting the engine that hot for 20 minutes and taking advantage of this potential solution.
Long bursts of acceleration will undoubtedly get the engine hot. But aside from a race track, where can anyone realistically drive full-on/back-off over and over again ......for 20 minutes straight? It would be nice if we had an Autobahn where we could cruise at 120 mph for 40 miles, but we don’t. Sorry, but I can’t see any of us actually getting the engine that hot for 20 minutes and taking advantage of this potential solution.
stuck24
so?
move to Texas.
It's not about car speed, it's about the speed of the engine revs.
just take the sound advice of genius VW engineers and spend less time questioning their patented advice.
Run the car in 5th gear at 70 mph for a steady 20 minutes once a week. And maybe 4th gear at 65 mph for 10 minutes once a week if gas is cheap in your hood. :happyanim:
I live 16 miles from work. It';s a nice freeway jaunt for me... I guess I am one of those who can easily do an Italian tuneup cos I live in the 'burbs. I have it a bit easier cos I go to work at 9am...and go home at past 630 so I have some nice stretches of 60-70 mph road in front of me.
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I don't know if the VW engineers are lying or not but in the patent application they suggest that holding the engine at over 3000 rpm for 20 minutes will do the trick.
We can talk all day about how many angels can dance on the head of a pin but that's what VW recommends. That would be similar to a drive down the autobahn. And, interestingly, the carbon build up seems to be less of an issue there.
We can talk all day about how many angels can dance on the head of a pin but that's what VW recommends. That would be similar to a drive down the autobahn. And, interestingly, the carbon build up seems to be less of an issue there.
barische
Go Kart Champion
run the lines to the exhaust..
Hmm the link to that patent is pretty interesting. I skipped down to where I found the part about keeping the engine above 3000 rpm for 20 min as I don't have the time to read the entire thing, so I may have missed something.
With that said, here are my thoughts:
1. If the engine just needs to be above 3000 rpm, cruising in 6th at freeway speeds is what, 3100-3200? I would be interested to see what the valves look like on a car that has a long commute. Theoretically, if you have a 30-40 minute commute on the freeway, your valves should be fine then, correct?
2. What do the valves look like on the tuning companies (APR, UNI, GIAC, REVO) race/shop cars? Those probably see more high heat than any of our cars that we drive to/from work and push the go pedal on the on ramps. When on the track, the rpm is almost always (I would imagine) above 3000 rpm to stay in the power. Their valves should be spotless, right?
3. Assuming I am reading the patent correctly, it was filed in 2002 and published in 2005. Therefore, VW has known about these methods (and felt strongly enough to file a patent) for 11 years. If it really works, why haven't they put it in the car manual? They have an engine break in procedure in the manual, why not this if for nothing more than to cover their butt when someone wants their valves cleaned under warranty? All they would have to say is "your manual says to drive in this manner and the valves will be fine, clearly you didn't." Maybe if they put that in the manual and made the issue well known, they fear the consumer would see their product as inferior, thus not purchasing the car. If I were the average consumer (not on car forums/know about direct injection issues), I probably wouldn't know about carbon build up unless the dealer told me to drive a certain way before taking delivery of the car, or I took it in for service and the tech told me the valves need cleaned.
Obviously, I am being a bit of a skeptic, but in my opinion, those are valid arguments and I would love to see the first two proven wrong. Just because there is a patent, doesn't mean it is the solution.
With that said, here are my thoughts:
1. If the engine just needs to be above 3000 rpm, cruising in 6th at freeway speeds is what, 3100-3200? I would be interested to see what the valves look like on a car that has a long commute. Theoretically, if you have a 30-40 minute commute on the freeway, your valves should be fine then, correct?
2. What do the valves look like on the tuning companies (APR, UNI, GIAC, REVO) race/shop cars? Those probably see more high heat than any of our cars that we drive to/from work and push the go pedal on the on ramps. When on the track, the rpm is almost always (I would imagine) above 3000 rpm to stay in the power. Their valves should be spotless, right?
3. Assuming I am reading the patent correctly, it was filed in 2002 and published in 2005. Therefore, VW has known about these methods (and felt strongly enough to file a patent) for 11 years. If it really works, why haven't they put it in the car manual? They have an engine break in procedure in the manual, why not this if for nothing more than to cover their butt when someone wants their valves cleaned under warranty? All they would have to say is "your manual says to drive in this manner and the valves will be fine, clearly you didn't." Maybe if they put that in the manual and made the issue well known, they fear the consumer would see their product as inferior, thus not purchasing the car. If I were the average consumer (not on car forums/know about direct injection issues), I probably wouldn't know about carbon build up unless the dealer told me to drive a certain way before taking delivery of the car, or I took it in for service and the tech told me the valves need cleaned.
Obviously, I am being a bit of a skeptic, but in my opinion, those are valid arguments and I would love to see the first two proven wrong. Just because there is a patent, doesn't mean it is the solution.
stuck24
so?
cos then people would start whining about false MPG advertisements. I can't imagine beong instructed to run the motor at 3700 rpm for 20 mins once a week to blow out carbon AND lose fuel efficiency. LOL
In Europe, their FSIs/ TSI's don't carbonize their valves as much because their motors run in lean burn mode often...
maybe their fuel has something to do with it tooooo. who knows.
sethdude
Pobody's Nerfect.
Both my 1974 BMW 2002tii and my 1984 Rabbit GTI are doing 3,700 RPM at 65-70mph. I've gotten used to it, but I think drivers of modern cars will freak out over the noise and such. people are used to driving cars with a high top-speed and a LONG final drive.
That said, I've been driving my cars spiritidly (regular trips to redline) for years, and never had any mechanical problems as a result. Ever. Engines are designed to reciprocate within a given rpm range (indicated by the red line). You will not increase wear or damage on your car by operating it withing these ranges.
you will need to check your oil regularly and replace your timing equipment on time, but you should be doing this anyways.
i would bet that 90% of failures due to high engine speeds within factory specification are due to owners neglecting maintainance.
Just keep the oil clean and the revs up.
stuck24
so?
Most of us here have no trouble running our motors at 3700 rpm for an extended period of time. However, the vast masses will resist, especially because they won't be getting near the 32 mpg they were promised.
I had 91 Miata: car ran 3600 rpm at 70 mpg in top gear.
Engine loved every little rev... ran like tops when I sold it after 5 years.
I would not use it for diesels as it contains alcohol but I've used on my A4 3.2 Quattro a few times and a few other gasoline motors with good results. The Audi is a DI as well and known for carbon build-up issues. To each his own.
I also notice a lot less carbon build-up using chevron 93.
McQueen77
Banned
its realistic for anyone that lives in close proximity to a highway or freeway that isn't crawling with traffic all day. if all you do is drive to and from work during rush hr. then you are probably screwed but if you take the car out at night or are ever off during the week, its possible. i live in LA County but happen to be off of probably the last open freeway in southern california, the 210 east/west. i also have a lot of backroads near me. during the week if I am not working, i drive the wife's Tiguan during the day and at night, to get out of the house i'll take the GTI out and pretty much drive it hard for about 20-30 minutes. just getting out on the highway in 4th and 5th gear and pulling along at 4-4500rpms consistently. my drive to work is 70% highway and i do the same that way.. when i change the plugs at the 40k service i want to send a boroscope down there and see how things are looking buildup wise. ive been driving the way i mentioned since i had the car so im curious to see if the geniuses at VW are right.
this. i think the buildup is definitely a symptom of the fact that many people spend most of the time in their cars idling or inching along in traffic, obviously not ideal conditions for any engine and even worse for ours.
Update
Any pics about the can installed? I'm really interesting in doing it...pls instructions....thx
Any pics about the can installed? I'm really interesting in doing it...pls instructions....thx