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Discussion Starter · #1 ·
The TDI guys have started cleaning their turbos by removing the exhaust pipe and spraying oven cleaner inside on the vanes to remove carbon buildup. Spray generously, let sit 15 minutes, gently rinse with water, repeat a couple of times.

Any reason not to do this on a 1.8T? It saves removal of the turbo. Are the TDI turbos similar inside?

Don
 

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The TDI guys have started cleaning their turbos by removing the exhaust pipe and spraying oven cleaner inside on the vanes to remove carbon buildup. Spray generously, let sit 15 minutes, gently rinse with water, repeat a couple of times.

Any reason not to do this on a 1.8T? It saves removal of the turbo. Are the TDI turbos similar inside?

Don
You might want to be very careful with rinsing. Any cleaner (sodium hydroxide) left on the vanes will eventually pit them, particularly at temperatures noticeably higher than those of a self cleaning oven.
 

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You might want to be very careful with rinsing. Any cleaner (sodium hydroxide) left on the vanes will eventually pit them, particularly at temperatures noticeably higher than those of a self cleaning oven.
easy off is safe for enamelled or porcelain surfaces but I not sure if your turbo impeller and parts are safe, did any of those guys try spraying into the intake valves too since those get encrusted with carbon buildup, but try it and let us know what happens:salute:
 

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I don't think a gasser will put nearly as much carbon/soot on the impeller as a diesel would.

You'd probably get better results sucking Sea Foam into the intake.
 

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I wasn't aware that carbon buildup on the vanes was a big enough problem to warrant such a strong and unapproved cleaner. Sure the TDI boys weren't yanking your chain?

I always go by the "How stupid will I feel?" scale. I visualize going to buy a turbocharger, and having to admit I put oven cleaner in the old one.
 

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Umm, I've pulled 3 turbos off my car now, and have not seen a problem with carbon buildup, though I haven't pulled one off with more than 45k miles on it. I can definitely understand a TDI producing a lot more buildup and soot in a turbo, because thats what they do. Produce soot and lots of unburned diesel fuel. The ones with cats don't normally smoke out the back.
 

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Umm, I've pulled 3 turbos off my car now, and have not seen a problem with carbon buildup, though I haven't pulled one off with more than 45k miles on it. I can definitely understand a TDI producing a lot more buildup and soot in a turbo, because thats what they do. Produce soot and lots of unburned diesel fuel. The ones with cats don't normally smoke out the back.
and i thought soot was a by product of any diesel and not unburnt diesel fuel.
 

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Yes, it is. And also, diesels like to not burn all their fuel, another reason why almost all diesel vehicles turbochargers, because a turbo atomizes a lot of the unburned fuel, resulting in better fuel efficiency.
 

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Yes, it is. And also, diesels like to not burn all their fuel, another reason why almost all diesel vehicles turbochargers, because a turbo atomizes a lot of the unburned fuel, resulting in better fuel efficiency.
got a link for that? Because I don't think that's possible. The turbo serves one purpose, to inject more air into a smaller engine. It creates more power. The design of a diesel engine itself is the efficiency. Even non-turbo diesels are extremely thrifty in the mpg department
 

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got a link for that? Because I don't think that's possible. The turbo serves one purpose, to inject more air into a smaller engine. It creates more power. The design of a diesel engine itself is the efficiency. Even non-turbo diesels are extremely thrifty in the mpg department
I don;t think a turbo atomizes alot of the unburnt fuel but it is the fuel injector's that do that. The nozzle spray pattern, fuel pressure and amount of air present in the intake manifold will produce atomization of the fuel.:salute:
so the more air in the intake manifold will make more atomization i assume is what he is mean.:salute:
 

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As a driver of a 04 TDI, I have never heard of anyone using oven cleaner. Even if they did, I wouldnt do it.
but if you got access to the impeller you can physically remove the carbon and soot, so why need the oven cleaner??

you know being a mechanic i am a non believer of these remedies in a can.:crazy:
 

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Ok, the turbo itself burns the unburned fuel because... oh yeah... its REALLY HOT. Why is that hard to understand? It's 100% true. Look it up. Just because I'm 18 and teens have been given a bad name especially on this site, doesn't mean I'm a retard.
 

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Ok, the turbo itself burns the unburned fuel because... oh yeah... its REALLY HOT. Why is that hard to understand? It's 100% true. Look it up. Just because I'm 18 and teens have been given a bad name especially on this site, doesn't mean I'm a retard.
your not a retard, just misinformed. Nobody is slamming you either. really, take it easy :thumbup: The turbo does not burn unburnt fuel either. And why are we arguing over unburnt fuel? Unburnt fuel is fuel wasted and not a good thing to have in the exhaust. It can ruin a turbo and especially the cat(s).
 

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Discussion Starter · #15 ·
From Wiki:

A turbocharger is a small centrifugal pump driven by the energy of the exhaust gases of an engine. A turbocharger consists of a turbine and a compressor on a shared shaft. The turbine converts kinetic energy from the engine exhaust's velocity and potential energy from the exhaust's higher-than-atmospheric pressure into rotational kinetic energy, which is in turn used to drive the compressor. The compressor draws in ambient air and pumps it into the intake manifold at increased pressure, resulting in a greater mass of air entering the cylinders on each intake stroke.

The objective of a turbocharger is the same as that of a supercharger; to improve an engine's volumetric efficiency by solving one of its cardinal limitations. A naturally aspirated automobile engine relies mostly on the downward stroke of a piston to create an area of low pressure in order to draw air into the cylinder through one or more intake valves. The pressure in the atmosphere is no more than 1 atm (approximately 14.7 psi, or 1 bar), so there ultimately will be a limit to the pressure difference across the intake valves and thus the amount of airflow entering the combustion chamber. Since the turbocharger increases the pressure at the point where air is entering the cylinder, a greater mass of air (oxygen) will be forced in as the inlet manifold pressure increases. The presence of additional air mass in the cylinder makes it possible to create a bigger explosion if more fuel is injected, increasing the power and torque output of the engine.

A turbo adds power to any engine, but does not increase fuel economy in the same size engine. It gets more power out of a small engine as opposed to using a bigger block.

Diesels are much dirtier than gas, so they will soot up everything much faster than a gas engine.

Has anyone seen the inside of a high mileage turbo from the 1.8T? Maybe I am thinking mine may be dirty for no good reason.

I keep mine working pretty hard most of the tiime with lots of highway use and I usually upshift late as opposed to lugging the engine. Being in 5th at say 50MPH/80KPH I feel creates lower exhaust temperatures and will be more likely to create carbon buildup on the valves, injectors, and in the turbo than being in 4th at the same speed.

Thanks for the replies so far.

Don
 
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