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Been reading some posts here. My understanding is that the stock 1.8T did not need to be cooled down. Am I wrong?


How about if you chip the engine and increase the boost to 1 barr? Should you start cooling down the turbo when you finish driving?
 

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Depending on your driving style you can do one of a few things... This assumes you are chipped because the stock 1.8T should never get to the point where the turbo needs cooldown time...

If you have the pedal to the floor until you pull in your driveway, either let the car idle for a few minutes or invest in a "turbo timer" which allows you to lock and walk away while your car continues to idle until the temp cools enough and it shuts down for you.

- or -

you can do what I do. If you have a decent commute (say 10 miles or more), save the last few miles or minutes for easy driving to allow time for the turbo to cool.

Once you get your oil changed, check for any signs of excessive sludge building up. If so, this means you are getting pretty warm. Definitely consider using full synthetic oil if you don't already, that will save your engine big time. Also, run a bottle of auto-rx through your system every now and again (www.auto-rx.com) that stuff is amazing at removing oil sludge buildup.

If you keep those oil lines clean and change your oil on schedule AND let the turbo havae enough time to cool through easy driving or a turbo timer, you should have no problems whatsoever.

Good luck!
-Chris
 

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i usually just idle for 30-60 seconds... by the time i get my windows up, grab my cell phone, turn the radio down, that covers it...

and easy driving the last mile or so before i hot my destination helps as well...

did the same thing with the Evo and never had a problem...
 

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Same here...always. Since I chipped a few days ago, I notice the engine compartment is a tad warmer (or my imagination?) so I wait a little longer. May have to get a turbo timer when my kids are old enough to drive it.....
 

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Just a quick comment: The normally chipped 1.8t turbo does indeed get hot enough to coke the oil and should do the cool-down period after boost. Probably not as acute as the chippers, but still an issue. Just do a search for the number of people who have gotten the sludge problem. A high quality synth helps, but does not totally alleviate this problem.
 

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I'm not chipped but I live on top of a hill with a pretty long ascent. If I come up the hill and pull into the drive and immediately pop the hood, the turbo is glowing.

My solution is to take the alternate way home, which let's me run along the ridge line with almost no need to touch the gas (I'm not in boost at all). No glow when I come home that way.

Also, while I'm cruising that last half mile, I shut off the a/c and just run the fan to dry out the a/c system. So, I get no turbo glow and my a/c smells as fresh as a spring day!
 

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Even on an un-chipped car, do this sometime at night: After cruising along at a steady 45MPH in 5th gear, over rolling terrain, stop and pop the hood. Even with that gentle kind of driving, you'll see the turbo glows somewhat, and it takes about 4 minutes of idling for the glow to subside completely. 4 minutes is a long time to idle every time you stop the car, and in the end that may not be good for the car either, but the one thing I know for sure is the turbo glows for quite a while after driving 'gently'.

Does anyone know if running the heater for a bit would help it cool off faster? Sometimes I crank up the heater if I pull off the highway and don't want to wait 4 minutes, but I haven't checked if it stops glowing sooner.
 

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A-Tiller-the hun said:
i usually just idle for 30-60 seconds... by the time i get my windows up, grab my cell phone, turn the radio down, that covers it...

and easy driving the last mile or so before i hot my destination helps as well...

did the same thing with the Evo and never had a problem...
ditto plus maybe a lil extra time if i'm not in a hurry
 

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RechtsFahren said:
Does anyone know if running the heater for a bit would help it cool off faster? Sometimes I crank up the heater if I pull off the highway and don't want to wait 4 minutes, but I haven't checked if it stops glowing sooner.
The heater pulls very little thermal energy from the engine bay (air is easy to heat, compared to oil, or coolant, or water). It's a drop in the bucket, so to speak. Drive serenely for the last mile or so, and you'll be fine. The airflow over the main radiator and through the engine bay does much more for cooling the whole system than the cabin heater can.

You could also buy a turbo timer. I use a Blitz DTT DCII.
 

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Yeah I wasn't thinking the heater would make the air under the hood cooler, but rather it would act as an additional radiator for the coolant. The cabin heat comes from the coolant.

On hot days in cars with cooling issues, turning the heat on can be the difference between overheating and making it home. It's possible to dissipate a lot of extra heat this way (I know because on a 1970 2.8l the temperature needle could get up to around 225F and turning the heat on would immediately take it back down to about 190F), but I just didn't know how much that would help the turbo housing cool off faster.
 

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rechts - I don't think the cabin heater exchanges much energy with the coolant system - it's a stop-gap at best for limping home, like you said. The big radiator up front and the two big fans behind it do the majority of the cooling work. In warm weather, the driver-comfort::turbo-cooling ratio is not in the driver's favor on this one. Drive easy that last mile and don't worry about it.
 

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ericpeterman said:
Just a quick comment: The normally chipped 1.8t turbo does indeed get hot enough to coke the oil and should do the cool-down period after boost. Probably not as acute as the chippers, but still an issue. Just do a search for the number of people who have gotten the sludge problem. A high quality synth helps, but does not totally alleviate this problem.
It does, eh? What temperature measurements have you taken of the inside of the bearing cartridge?
 

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TheJezter said:
Depending on your driving style you can do one of a few things... This assumes you are chipped because the stock 1.8T should never get to the point where the turbo needs cooldown time...
. . . I don't completely agree with that. My car is stock and I've have my whole exhaust manifold as well as the turbo glowing red before. Bottom line is (like most people already have said) you should let your turbo cool down after hard driving.
 

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There's actually two important things - "cool down" and "spin down."

Even if your turbo is already "cooled down" due to gentle driving, for absolute best wear you should still let it idle for a minute or two. This gives the turbo time to "spin down". The turbo bearings have such low friction that the turbo continues to spin at high rpm for a long time after load is removed. The turbo depends on oil pressure for its bearing surfaces. When you turn the car off, the bearing surface collapses. Best to have this happen at the lowest possible turbine speed. High turbine speed + zero oil pressure = scored turbo bearing surfaces.
 

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yea rusty, but the shaft will be spinning even at idle. You'd have to be running at full bore and quickly flip off the ignition for it to be a problem, and even then, there's so little inertia in those components and relatively significant forces slowing the whole thing down from the compressor side. While I haven't done any testing, you'd have to show me some evidence to convince me that it's something to spare any brain cells thinking about.
 

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What does "the bearing surface collapses" mean? The flow of oil is removed when the engine is turned off, but there is still oil present in the turbo. The "stagnant" oil still has some viscosity and should provide some protection. Does the flow determine the oil film thickness, or does the viscosity determine it?
 

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I wonder if the shaft doesn't act as a sort of centrifugal pump for the oil that will clean itself without a supply. However I still think the spin-down time from idle is going to be practically nil and sitting at idle for a time won't improve the situation.
 
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