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Congealed Fat (oil) in my engine

I have an 99 vw gti and was told the build up is because of short trips. Is there anything I can do to avoid the build up and does it eventually lead to an early engine death. I only have 71,000 miles and I want this thing to go to at least 150,000

Change with the recommended oil (make sure, VW is picky on oil grade) under the severe schedule on miles and time. Make sure you have a trip a week or so that brings your car to full operating temperature (a half hour on the freeway or so) to get any fuel and water out of the oil. How did they know you have a sludge buildup? VWs of that era can have a sludge problem, I’ve heard.

Averaging only 7,000 miles per year, you may want to consider a fully synthetic oil, like Mobil One, if it meets VW specs. Synthetic oils are far less prone to sludging up.

What did the mechanic that diagnoised the “build up” recommend? Surely he would like to see you more often and use more expensive oil. Now that he has you scared you would probably agree to just about anything.

Hard to believe that the mechanic would let you get away without selling you a plan.

This is (another) case of a manufacturer trying to compensate for a poorly designed engine by specifying special motor oils in an attempt to cover up their mistakes…Some times it works, sometimes it doesn’t…

thanks for the feedback… after I left the message I forgot to include that I do get the oil changed every 5000 miles it is done at a VW dealership and they use 5w30 castrol gtx synthetic. There isn’t anyway to go 1/2 hour I only live 7 miles away from work. If I drive the speed limit I could tack on about another 5 minutes or 2. I could find something to do to drive 1/2hr once a week. I noticed the buld up when I remove the cap to clean it with a paper towel. Is there any additives that I could add to dry up the condinsation? and that’s not the only problem this car has from that era I believe the workmanship on it was on the down side back then. thanks again

Moisture is one of the byproducts of combustion, so your engine produces moisture every time that it runs. The problem that has occurred in your engine is that the engine never gets hot enough–for a long enough period of time–to evaporate the moisture that is accumulating in the oil.

Over time, this leads to sludge that clogs the oil screen and the very narrow oil passages in the engine, with the end result being oil starvation to the engine’s sensitive bearings. Oil starvation of the bearings leads to an early demise for the bearings and other engine parts.

Now that you know about the problem, you have to try to remediate it. I would suggest that the next time you change your oil, have the oil change done again in a couple of weeks in order to have as much accumulated sludge as possible cleaned out of the engine by the fresh, detergent-laden oil.

Then, switch to synthetic oil. This is much more expensive, but it is still much cheaper than replacing your main bearings or replacing your engine. Consult the maintenance schedule that came with the car (inside the Owner’s Manual, perhaps?) to see what the “severe service” or “extreme service” interval is for oil changes. It will be expressed in terms of both elapsed time and odometer mileage, with the proviso, “whichever comes first”–in other words, “every X months or X miles, whichever comes first”.

If you use synthetic oil and if you stick to the extreme/severe service schedule for oil changes and other maintenance, you will–hopefully–be able to meet your goal of having the engine last until 150k. You should also try to take the car out for a drive of at least 45 minutes once a week, in order to help burn off the accumulated moisture in the engine and in the exhaust system. However, please bear in mind that whether you can get 150k out of this car is predicated on how much damage has already been done to the engine, and none of us knows the answer to that point.

Your car is living a hard life. 7 miles one way, back and forth to work, is not enough for the engine, transmission, exhaust system, etc, to fully warm up. That’s why the condensation never dries out and the water builds up in the oil.

Are we to believe you NEVER go anywhere in this car except to work and back? No weekend trips, no highway drives, no out-of-town travel, no Sunday drives in the country? I would have to ask why you own a GTI, since they are oriented toward people who love to drive, and drive just for the fun of it. Perhaps that’s not you, and if that’s the case you have only two choices:

Change the oil more frequently, or

Change your driving habits.

The engine needs to warm up, reach full operating temperature, and STAY there for a while. Take a trip. Go visit family and friends, even the ones who live far away. This car needs to be DRIVEN. Drive it on the highway, or flog it up and down your favorite back road, for an hour or so once in a while.

You don’t have to do this every day, just once every few weeks to drive out all the condensation.

thanks again for the advice

and yes I don’t go many places that much anymore but now that my daughter is a bit older we will pick a day and take a day trip when I pick her up from the sitter after work. I think I can drive it long drive every few weeks… I was just going to get a well used car for going to work and save the GTI when I want to drive farther than 14 miles round trip a day…

thanks again for the advice

I’ve had this same problem. I live in a small town and make many short trips. I’ve seen that “emulsion” in the winter. The cure for me was to install an engine heater. I just plug it in at night. Works great and instant heat is nice when it’s really cold outside.

Is Castrol GTX synthetic not fully synthetic?

I don’t have the citations handy, so I hope that I am not spreading urban legends here, but I read that when Castrol got in to the synthetic oil market, they lobbied and successfully got the definition of ‘synthetic oil’ relaxed to allow the use of base petroleum oil stocks as a starting point. I also read that Mobile subsequently started using petroleum oil stock so that they could be price-competitive with Castrol. Both discussions indicated that it does not make any difference - that the end product is indistinguishable from made-from-scratch synthetic oil.

I suggest you just change your oil 3 times a year, no matter how low the mileage is. Synthetic oil can get waterlogged as easily as regular.