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Is it bad if my engine never reaches operating temp?


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2004 Forester with SOHC EJ25

 

I have a 2 mile/5 minute commute and in the winter my car never reaches operating temp unless I idle it beforehand for longer than I drive it. I would consider just riding a bike or something, but there is almost as much elevation change as there is distance traveled, so on the way to work I would freeze to death coasting down a huge hill and on the way home, I would get destroyed trying to climb the hill.

 

I know that your engine seems the most wear before it reaches operating temperature and I'm wondering if installing a block heater will help enough to be worthwhile. Is there something else I should try instead (or also)?

 

Advice appreciated.

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Short trips are considered 'severe duty' and can be as bad for cars, in different ways, as off-road use, racing, or overloading with cargo.

 

Is the car ever used for longer trips? On weekends?

 

First, the maintenance schedule has a TIME side and you should do maintenance according to it. (exceptions 'might' be things like air filters and sparkplugs - but even fluids degrade over time - plus, with low usage like you experience, they collect moisture from condensation)

 

you should also consider re-fueling before the car indicates empty - maybe at the half-way mark.

 

I see nothing wrong with you idling the car a little longer and/or using a block heater - you will get poorer mileage, but you 'may' be less likely to carbon foul the plugs and engine oil may be better able to 'boil-off' any moisture collecting in it.

 

If it hasn''t been done, you are WAY overdue for a timing belt service too.

Edited by 1 Lucky Texan
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Block heater to drive moisture out of the engine is good idea. Lots of idling is not good. It would be better to drive an extra mile. Good to get the transmission and the rest of the driveline warmed up too, for the sAmerican reason, drive out moisture. Another thing short trip is tough on is the exhaust system - if it doesn't get hot enough to dry out the moisture released during combustion.

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Most of my trips are pretty short. 10 miles or less, with longer stuff a few times a month. I change my oil and filters at a pretty aggressive schedule. Timing belt service has been done twice actually. I am aware of how hard short trips are on a car, I'm just wondering how much of a problem it will be to add never getting up to temp into the equation.

 

Seems like the block heater is a good idea, I just have never used one and I'm not sure what kind of temp increase I will see. Would an oil pan heater be a good idea, too. I live in PA and it doesn't get SUPER cold all that much, so I don't know what I really need.

Edited by jmoss5723
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A block heater does not burn moisture out of the engine, the only thing that does is letting the oil reach operating temp above 212 degrees and driving with it fully warmed up for several minutes. Once a week take the car for a 15 minute drive on the highway. It'll cost you a couple bucks in gas every month but in the long term you'll save your engine. Also, if you aren't already doing it, use a good synthetic oil. Synthetic oil helps prevent corrosion from water and acids built up from increased blowby of not reaching operating temp.

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synthetic oil also keeps 'varnish' in solution better - expect your oil changes to look darker.

 

I suppose if your spark plugs look normal, that may be an indicator that the low-use isn't building carbon on valves or elsewhere in the combustion chamber.

 

 

recent guidelines on tires also discourage driving on old tires.

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honestly, there may be 'diminishing returns' at altering your treatment of the car very much. Yeah, we can theorize about this or that change but, without sending fluids in to Blackstone or Polaris labs, examining plugs, throttle plate and maybe internals for deposits, etc. , hard to say exactly how to tweak the maintenance to optimize the lifespan of the car. A weekly/bi-weekly highway runas suggested above  and not letting the car sit around for weeks with only 1/4 tank of gas might be the most 'practical' things you could do. 

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Yea, I'm not  gonna get into snakeoil and additives to keep moisture down etc. Just driving the thing at operating temp for 15 minutes ever now and again is the best maintenance you can do to any car. I used castrol GTX high mileage full synthetic in my last ej22 with over 200k miles on it. It's like $15 at Walmart for a 5 quart jug. When I switched from conventional it quieted down noticeably. No procedure for switching, there are a lot of myths around synthetic oil. You need to flush the engine, you can't mix synthetic and conventional, you can go 20k on an oil change, blah blah blah blah BS.... A lot of it has historical relevance from the early days of synthetics, however no longer true.

Just change the oil and filter like normal and pretend nothing changed. If you have to add oil somewhere and can't buy synthetic, put conventional in there.

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Unless every possible oil seal/oring/gasket on the engine is brand new, don't switch to synthetic oil. The stuff is like water and will pour out through any point where you currently have only minor seepage.

 

Stick with regular oil if that's what you've been running.

 

The reason short trips are bad is because of just what you have. 2-3 mile drives where the oil and other fluids don't get to full operating temp. A block heater will help, but Idling for 3-5 minutes will give you roughly the same temp increase when you start driving. Where a block heater really becomes important is during cold starting when oil is very thick, and the flow is very slow. PA gets cold enough that you could certainly justify using a block heater. It will make starting easier in the winter, as long as you remember to plug it in.

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Put a fuel stabilizer in the gas tank, I like to put a hanging bag of desiccant salts in the car to absorb moisture and prevent mold, but I live in the soggy PNW.

 

This would probably be a good place to start:  Car Storage FAQ:  Read if you're going to be storing your car for more than 30 days

 

It may not all be applicable to your situation, but a lot of it will be.

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Well my engine had a full reseal when the HGs and TB were done a year and half ago, so leaks with synthetic should be nothing to worry about.

 

I do get a decent drive in at least a few times a month, if not once a week. I will get the block heater since it's only like $40 and it certainly can't hurt.

 

Sounds like I probably don't really have much to worry about. Thanks for all of the input!

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