VW Diesel info

[Aleks]

Hey guys,

Gf's brother just got an 06 Golf Tdi. He did some reading online and read that it needs to be driven on the highway a lot to clean the engine out and he needs to put fuel additives in so the fuel doesn’t start gelling.. and that he needs to use really really good oil.

I don't know much about diesels and I know there are people on here that do. Is any of this stuff true? what are your recomendations?

[yellowsnow]

for a brand new vw diesel? I doubt you need to be putting any additives or any of the stuff. It's not like you're using biodiesel, which is known to gel in colder weather. petro diesel would not gel so easily i think

and since it's a brand new car, he doesn't need to clean the engine out by driving tons of highway... if you do regular maintenance, a diesel engine should last a LONG time

[Tik-Tok]

He shouldn't have to worry about it until the warranty is up. Sometime shortly before it is up though, he should have VW clean physically take off his intake manifold and clean it up, then after the warranty is done he needs to get it retuned.

While I was researching VW diesels a couple of years ago I found almost everyone had that problem, the intake manifold gets severely clogged because of the way the car is tuned to pass Canadian emmisions laws, but retuning it a certain way will stop this from happening, but it won't pass emmisions laws then, and could void your engine warranty if VW wanted to be dicks about it.

[kevjs]

He should not have to use additives to prevent the fuel from gelling. afaik the diesel sold in the winter is a slightly different blend than the summer to prevent gelling at low temps. I beleive VW states a specific type of Castrol Syntec oil is required, this may or may not be tru but I did use it in my TDI, the cost difference is minimal anyways.

I had a 2005 Jetta TDI that was driven every day last winter and always parked outside and never had a problem with the fuel gelling. I didnt see any buildup in the intake on my TDI but I was running a dieselpower box on it and was regularly driving on the highway.

[nismodrifter]

Originally posted by Aleks
Hey guys,

Gf's brother just got an 06 Golf Tdi. He did some reading online and read that it needs to be driven on the highway a lot to clean the engine out and he needs to put fuel additives in so the fuel doesn’t start gelling.. and that he needs to use really really good oil.

I don't know much about diesels and I know there are people on here that do. Is any of this stuff true? what are your recomendations?

Additives are a waste of money.

The car is perfect for driving in the city. Shift at like 2500 rpm and really get on it sometimes. You can buy ULSD at shell stations so intake clogging isnt as big of an issue as it was before.

You need to use the recommended oil for that engine.

[Aleks]

Thanks guys.

[SOAB]

the recommended oil for your car is Castrol 505-01. i have yet to see this available anywhere but a VW dealer.

[cloud1314]

if ur interested i have 505.01 oil
pm me for more info

[Zero102]

There is some half-information in this thread.....
Diesel fuel sold in north america in the winter months is required to be 'winterized'. This means that it must not gel in 97% of normal weather. If we are in the coldest 3%, then it is possible for properly treated diesel fuel to gel.
For this reason, buy a bottle of anti-gel. If you see an extreme cold snap coming, and you fueled up some time ago, then add anti-gel to your tank, and top up.
It is a good rule of thumb to keep your fuel tank more than half full in the winter time to help keep moisture out.

As for highway/city driving..... there is much debate on this issue whether the intake clogging is a result of sulphur in our fuels, driving habits, random luck, whatever.
I have an 05 golf (same car) with 33,000km on it. Looking down the intake is a scary sight, it is clogging badly. I drive with a very heavy foot when in town, tow heavy trailers and take long highway trips. I do everything that everybody reccomends to help keep the intake clean and it is not working.
Every 50,000-100,000km remove the intercooler hose and possibly the anti-shudder valve to inspect the intake manifold. It is hard to get a good look in there with the anti-shudder valve in place.

If you want a real source of information, go to
www.tdiclub.com

Oh yeah, DON'T FORGET THE PROPER OIL FOR THE PD ENGINES. Just recently VWOA has approved 506.01/507.00 oils for PD engines. This is good because all 505.01 oils are group III oils, which means that they are refined petroleum base stock and not true synthetics (although Castrol won the rights to brand them synthetics....). 506.01 is a 0W30 GIV/V oil, and 507.00 is a 5W30 GIV/V oil. Both are far superior (although more expensive) to 505.01. I run 506.01 in the winter, and will be switching to 507.00 for next summer.
There is a large discussion on this over on tdiclub.

[Aleks]

thanks.
I will pass on the information.

[codetrap]

.

[Zero102]

A fuel warmer? Let's see the details, come on ;)

I'll elaborate.

They have a fuel recirculation system, but no warmer. If the fuel in the filter has gelled you are hooped. Basically, when fuel arrives at the injectors (this would be a PD engine, so unit injectors), only some of it is used. The rest of it is sent back to the fuel filter. The injectors get quite hot from operation, and they heat the returned fuel somewhat. Also the fuel passages run through the cylinder head (PD models only), and this heats the fuel in them somewhat as well. This fuel is returned to the fuel filter, which has a thermostatic tee on the top of it. This is a little T valve with a temperature activated flapper in it. Once the fuel coming back hits 40*C, it is returned to the tank instead of being recirculated in the filter. This way the engine can continue to run on the warmed fuel in the filter as the rest of it is pumped back to the tank to warm it up. The catch is...... THERE IS A FUEL COOLER! It is a small radiator looking thing located under the passenger side of the car about half-way to the tank. This is to prevent fuel overheating in hotter weather, but when it is -40*C out, it can cause the fuel to gel on it's way back to the tank.

So, the net effect is that a PD TDI running untreated fuel will start in colder temps than a VE TDI, but it probably won't run for very long (5-10km maybe?). This is why you still need to use winterized fuel, and occasionally anti-gel.
I bought a 1L bottle of anti-gel for $12 last winter, and have barely used any of it. It is very potent stuff. 1L treats 15 or 20 tanks, and I used it to treat 2. So, the cost per tank is very low.

Now, it is possible that they have changed this system in the MK V's, but I do not have one, the 06 golf isn't one, and an 06 jetta wagon isn't one, so it is not relevant here :)

Of course the above tips apply, visit only fuel stations that see a lot of diesel traffic in the winter. In Calgary lots of people like the husky truck stop on barlow and 32nd avenue. I personally use Centex, the one on 16th ave, and on 52nd street. Never had a problem with their fuel, and it consistently returns the best mileage of any diesel station I have tried.

As for plugging your TDI in, get a frost/TDI heater. I forget what the company is called now, but that is what I bought and it is fabulous. Super easy to install as well.
The dealership will tell you that they have an even better heater, made by Calix. If you really want to know the truth about that piece of shit ask me, I have a very long story about it, and why nobody should ever buy it.

All of this information and more can be found on tdiclub.

[tommy_W201]

VW's are equipped with a fuel warmer, which allows them to heat the fuel before it enters the engine, and in really cold weather it recirculates that warmed fuel back into the tank.
If it is the standard version, it is just the thermostate that Zero102 described.

If it is an extra filter heater (for example like this (http://www.diesel-therm.com/)) it only heats the filter itself. The injection lines as well as the injection-pumps will not be explicitly heated (regardless of the system). Thus, there might be damage to the injection if the diesel is gelling. That is mainly because the gel particles are then between the injection and the filter. This pre-heat system was usually designed to mimimize mechanical wear of cold engines and ensure proper lubrication in addition to that it heats the filter (preventing that it becomes blocked). Your injection pump does not have a seperate oil lubrication circuit anymore and is lubricated by the diesel itself. Guess what, if diesel becomes sticky you need a new injection pump.

I don't want to scare you with that. That car is in general pretty reliable, but it can be like a bitch below -20°C.

The entire fuel system of that car always circulates the fuel (after it is warmed up, as Zero102 described). Thus, you will have warm fuel in the tank regardless of the exterior weather conditions. The cooler is only used to avoid overpressure in the tank.

Usually, winter diesel does not gel up to -25°C. If the fuel became sticky one time, leave the car in your garage at +20°C for 24h in order to avoid damage.


He did some reading online and read that it needs to be driven on the highway.
This applies only to the older engines (like mine) that do not have a direct injection. The older injection nozzles injected the fuel pretty coarsely. Thus, there are unburned carbon particles that began to stick to the walls of the cylinder. If you rode the car (at high speed) on a highway you got rid of the unburned carbon (or at least a part of it). Today (applies to the car of your friend), the direct injection nozzles have a very high injection pressure that minimized that effect (the common-rail diesels especially). So you don't have to worry about it.

Please do not experiment with fuel additives. The injection is extremely sensitive of that car. I also doubt that this car is bio-diesel compliant.

[Zero102]

There is reliable evidence that biodiesel use up to ~B20 is beneficial even for PD TDI's. I plan to run between B10 and B50 next summer, depending on availability, pricing and weather.

The cooler is used to prevent over_temperature_ in the tank, not over_pressure_ ;) The addition of unit injectors caused a rise in fuel temps, and so with the PD TDIs they added the fuel cooler to keep the tank/incoming fuel temp lower. I guess in the hotter climates they were having troubles, since the hotter the fuel gets the worse its lubricative abilities get.

As for driving on the highway...... the only thing you need to do, is a good old fashioned italian tune up every now and again. I tow a trailer with mine, so going WOT for 5 minutes at a time up a mountain gives about the same end effect. If you have been driving conservatively, expect to see some visible smoke when you stomp on it. After repeated applications of the go pedal, the smoke will lessen/cease. :D