Top 10 mistakes which causes premature engine wear

[smc733]

Originally Posted By: finmile
Originally Posted By: philipp10
Your list shows me you feel NOT warming up your car is a big deal. I live in Minnesota, few if anyone warms up before driving but I rarely see a smoker. It would be interesting if we could see some real data nationwide that could actually prove this one way or another.


Well, to be precise I didn't say anything about warming up the car (which sounds to me something like minutes). I did say that driving away immediately at sub freezing temperatures could be (a little bit) bad for the engine.

I think that at really cold weather one should not start and go instantly, but wait a few seconds at idle first.

I like that rule Audi Junkie wrote at the thread below: “My rule is one second at idle for every degree below freezing. +22F = 10 sec at idle, +12f = 20 sec at idle and so on.”
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/657343/1

I’d like to enhance the rule by saying that you should always wait at least five seconds before you drive. I have made a habit of starting the engine always first and after that fasten the seat belt, tune the radio etc => and then go. Not the other way around. I think that idling more than this is a waste of time and fuel.

The only exception when I idle more is when I have snow and ice on top of the car. In those situations I first start the engine then remove ice and snow and then drive. I tried once the other way around and ended up having fog inside of the windshield. Didn’t like that to happen and since then have always started the engine first.


I do something very similar in the winter here, I will get in and start the car first thing, then put on my seatbelt, tune to the AM news, then drive slowly and accelerate easily, at least until the temp gauge starts to move. I figure I give maybe about 20-30 seconds max idling, and this is just enough to let the RPMs come down a bit from where the car first starts.

Some of the coldest mornings (10F or less), I can hear the starter run slowly, and the engine makes a bit of a unique sound for the first half mile or so, hard to describe, it just sounds "louder".

I do admit I make the car work for me on days with snow and ice. I fire it up and let it idle to get heat & defrosters go as I clean the snow off of it. That could be 3-5 minutes, but after cleaning it off, the last thing I want is to get into a freezing cold car.

 

[finmile]

Originally Posted By: smc733
I do something very similar in the winter here, I will get in and start the car first thing, then put on my seatbelt, tune to the AM news, then drive slowly and accelerate easily, at least until the temp gauge starts to move. I figure I give maybe about 20-30 seconds max idling, and this is just enough to let the RPMs come down a bit from where the car first starts.


If you mean the coolant temperature gauge, then a word of caution.

I used to think that when the coolant temperature gauge starts to move that “yeah, the engine is warm enough” and did hit the pedal to the metal. But at that moment the coolant is only about 50C (120F).

Also in many nowadays cars there’s a dead zone at the middle of the temperature range (which is build on purpose). The real coolant temperature can be anywhere in the 75C…105C (165F…220F) range, but the temperature gauge at the dashboard will not show it. It will stick in the middle, showing the normal operating temperature all the time.
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/2541527/2

In addition, usually the oil reaches its normal operating temperature far slower than the coolant.
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2505982

By combining these two things together I have created a rule of thumb to myself which I follow today. Always drive gently twice the time/distance that it takes for the coolant gauge to rise to the normal operating temperature. By following this rule I can be pretty sure that 1) The coolant has reached the normal operating temperature also in reality and that 2) The oil temperature is at least at the 50C+ (120F+) range.

 

[philipp10]

Originally Posted By: finmile
I have wondered which could be the main user mistakes which causes premature engine wear. And which of them are more severe and which less likely to cause any problems.
What do you think about the list below? Is it in the right order and do you come up with other issues that might happen? I know I know, it's a bit speculative list, but....

Top 10 user mistakes from worst to least severe (when done on a regular basis):
1) Let the oil level go below minimum
2) Drive WOT with a cold engine
3) Run full OCI while the car faces severe driving conditions (short tripping, stop-and-go driving, excessive idling, dusty conditions, towing or steep hills)
4) Use unnecessary thick oil (two grades up from the recommended), also in sub freeze temperatures
5) Run full OCI using mineral oil
6) Start to drive immediately (however gently) after engine has been started, also in sub freeze temperatures
7) Use the cheapest oil which fulfills the Owner's Manual recommendations
8) Exceed full OCI with a couple thousand miles (with synthetic oil)
9) Change the oil filter only every other (full) OCI
10) Run six months longer OCI than recommended (but miles within the recommended value)


I think your missing the elephant in the room here. The single biggest factor to premature engine wear is a poorly designed engine. If you are so un-fortunate to own an engine with a bad design, NOTHING you do will prevent it from becoming an oil burner.

 

[philipp10]

well I am going to play devils advocate here. What is the difference, to the engine if I warm it up by idling the motor verses warm it up by driving off at say, 1/6 open throttle. And to go even farther, why does it matter if I warm it up at idle verses just driving like I would as if it was summer? After less than 10 seconds of idling, the oil is circulating so why should it matter? The reason I ask is, I see people drive off all the time, not even giving a car 10 seconds of time but I rarely hear of oil related engine problems. I challenge you to explain why warm up is such an issue. I look forward to hearing your opinions.

 

[datech]

Originally Posted By: philipp10
well I am going to play devils advocate here. What is the difference, to the engine if I warm it up by idling the motor verses warm it up by driving off at say, 1/6 open throttle. And to go even farther, why does it matter if I warm it up at idle verses just driving like I would as if it was summer? After less than 10 seconds of idling, the oil is circulating so why should it matter? The reason I ask is, I see people drive off all the time, not even giving a car 10 seconds of time but I rarely hear of oil related engine problems. I challenge you to explain why warm up is such an issue. I look forward to hearing your opinions.



I think there is an urban myth about warm ups that somewhat came from the necessary warm up of aircraft engines, which are air cooled and with different metals and expansion rates requiring a thorough warm up prior to take off with full throttle. Nevertheless airplanes have the propeller spinning from the start, so there is some load there.

I remember riding on a DC-6 back in the 1960's and it took them almost an hour to get all of the cylinders firing right prior to take off ( it was an old plane).

I don't think the engine can 'feel' whether you are driving or just sitting so as long as you keep the RPMs fairly low for a bit no problem.

Overall the rest of the car has to warm up some, too. The tires, transmission, wheel bearings. I usually give it about 10 minutes driving for that.

 

[finmile]

Originally Posted By: philipp10
well I am going to play devils advocate here. What is the difference, to the engine if I warm it up by idling the motor verses warm it up by driving off at say, 1/6 open throttle. And to go even farther, why does it matter if I warm it up at idle verses just driving like I would as if it was summer? After less than 10 seconds of idling, the oil is circulating so why should it matter? The reason I ask is, I see people drive off all the time, not even giving a car 10 seconds of time but I rarely hear of oil related engine problems. I challenge you to explain why warm up is such an issue. I look forward to hearing your opinions.


Nice challenge

You are probably right on the fact that today's engines withstands quite a lot abuse without any visible symptoms.

About the need for slow heat up of the engines. I think it's at least about three things.

1) Temperature gradients inside the engine. If you warm up the engine with idling or by driving easily, the different parts of the engine are warming up more or less at the same pace. Thus the heat expansion is the same for all engine parts. Now, if you put a heavy load on a cold engine the pistons and valves are going to heat up (and expand) really fast while the rest of the engine (especially the engine block) is still cold (i.e. "small"). And this will lead to bad things...

2) The clearances in a cold engine are not optimal.

3) At sub freezing temperatures the oil is more like honey, not like water. So, as the lubrication is weak in a cold engine you don't want to floor it.

Personally I think the need to idle a little comes from the fact that at a really cold weather (let's say something like -20C) the engine is going to make some unpleasant noises at the beginning. For me it feels better to wait a bit (up to 60 seconds) for those noises to decrease or even go totally away before start to drive. It feels like you are making the engine a favour.

One more point. Even the anti-idling campaigns says that "30 seconds is enough". So, aren't they admitting with that sentence that some idling before driving can be a good thing?

 

[philipp10]

Originally Posted By: finmile
Originally Posted By: philipp10
well I am going to play devils advocate here. What is the difference, to the engine if I warm it up by idling the motor verses warm it up by driving off at say, 1/6 open throttle. And to go even farther, why does it matter if I warm it up at idle verses just driving like I would as if it was summer? After less than 10 seconds of idling, the oil is circulating so why should it matter? The reason I ask is, I see people drive off all the time, not even giving a car 10 seconds of time but I rarely hear of oil related engine problems. I challenge you to explain why warm up is such an issue. I look forward to hearing your opinions.


Nice challenge

You are probably right on the fact that today's engines withstands quite a lot abuse without any visible symptoms.

About the need for slow heat up of the engines. I think it's at least about three things.

1) Temperature gradients inside the engine. If you warm up the engine with idling or by driving easily, the different parts of the engine are warming up more or less at the same pace. Thus the heat expansion is the same for all engine parts. Now, if you put a heavy load on a cold engine the pistons and valves are going to heat up (and expand) really fast while the rest of the engine (especially the engine block) is still cold (i.e. "small"). And this will lead to bad things...

2) The clearances in a cold engine are not optimal.

3) At sub freezing temperatures the oil is more like honey, not like water. So, as the lubrication is weak in a cold engine you don't want to floor it.

Personally I think the need to idle a little comes from the fact that at a really cold weather (let's say something like -20C) the engine is going to make some unpleasant noises at the beginning. For me it feels better to wait a bit (up to 60 seconds) for those noises to decrease or even go totally away before start to drive. It feels like you are making the engine a favour.

One more point. Even the anti-idling campaigns says that "30 seconds is enough". So, aren't they admitting with that sentence that some idling before driving can be a good thing?


I agree with #1, the temperature gradients are probably an issue. I would have agreed to #2 until I started running synthetics, now it seems I don't hear odd noises at cold temps anymore.

 

[emg]

Originally Posted By: finmile
Also in many nowadays cars there’s a dead zone at the middle of the temperature range (which is build on purpose). The real coolant temperature can be anywhere in the 75C…105C (165F…220F) range, but the temperature gauge at the dashboard will not show it. It will stick in the middle, showing the normal operating temperature all the time.


At least you get a gauge. Our Forester only has a light to say whether it's too cold or too hot.

I presume the ECU makes all its decisions based on the oil temperature--which you can display on the LCD--so they saved a few bucks by not measuring water temperature and just having switches that open and close when it's too hot or cold.

 

[ragtoplvr]

One automakers cold weather tests involved starting the car, letting it idle 10 seconds, then wide open around the heated test track for 30 minutes, then cold soak again. It had to run right on all laps. After 5 cycles, engines were torn down, there would be no abnormal wear or they would fix it.

Another involved starting and idle for an hour. then repeat. Same thing, no abnormal wear. This one was harder in the carb days as rich mixture could promote scuffing.


Rod

 

[finmile]

Originally Posted By: emg
At least you get a gauge. Our Forester only has a light to say whether it's too cold or too hot.

I presume the ECU makes all its decisions based on the oil temperature--which you can display on the LCD--so they saved a few bucks by not measuring water temperature and just having switches that open and close when it's too hot or cold.


In my car the real temperature reading is there for the ECU for the whole temperature range. It's only decided not to show it to the driver in all temperatures. I would assume that there is a coolant temperature sensor in your car also. So, the designers of the car would have decided to go to the light only, because "it looks nice"

It would be interesting to hear from somebody who has the temperature light only, that can the real temperature be read with an OBD2 reader. Or are there cars really equipped only with some cheap switches.

 

[finmile]

Originally Posted By: ragtoplvr
One automakers cold weather tests involved starting the car, letting it idle 10 seconds, then wide open around the heated test track for 30 minutes, then cold soak again. It had to run right on all laps. After 5 cycles, engines were torn down, there would be no abnormal wear or they would fix it.


So, the WOT on a cold engine wouldn't hurt the engine either? If this would be the case then my original list of Top 10 would have shrunk to Top 1 only: Letting the oil level go below minumum. Dammit

 

[supton]

Seems trivial on modern DBW motors to not do WOT while cold--say no more than 75% until good and warm. Or whatever ma manufacturer thinks best.

 

[Doog]

Originally Posted By: philipp10
Originally Posted By: finmile
I have wondered which could be the main user mistakes which causes premature engine wear. And which of them are more severe and which less likely to cause any problems.
What do you think about the list below? Is it in the right order and do you come up with other issues that might happen? I know I know, it's a bit speculative list, but....

Top 10 user mistakes from worst to least severe (when done on a regular basis):
1) Let the oil level go below minimum
2) Drive WOT with a cold engine
3) Run full OCI while the car faces severe driving conditions (short tripping, stop-and-go driving, excessive idling, dusty conditions, towing or steep hills)
4) Use unnecessary thick oil (two grades up from the recommended), also in sub freeze temperatures
5) Run full OCI using mineral oil
6) Start to drive immediately (however gently) after engine has been started, also in sub freeze temperatures
7) Use the cheapest oil which fulfills the Owner's Manual recommendations
8) Exceed full OCI with a couple thousand miles (with synthetic oil)
9) Change the oil filter only every other (full) OCI
10) Run six months longer OCI than recommended (but miles within the recommended value)


I think your missing the elephant in the room here. The single biggest factor to premature engine wear is a poorly designed engine. If you are so un-fortunate to own an engine with a bad design, NOTHING you do will prevent it from becoming an oil burner.


+1 like my 2008 Toyota 2AZ-FE with the small oil return holes in the pistons.

 

[Urshurak776]

This thread topic is one of the biggest can of worms I have ever seen.....

 

[daves87rs]

Originally Posted By: Pop_Rivit
Originally Posted By: finmile

What do you think about the list below?


I think most of it's nonsense.


+1

I know a few cars that could prove most of that stuff wrong anyways...

 

[daves87rs]

Originally Posted By: finmile
Originally Posted By: andyd
Finmile, do cars in Finland rust out before the engine dies? Or does the engine/transmission wear out first? In Massachusetts, cars rust out before the engines die.


Warning

Depending on the source of information, the average age of cars in Finland is about 11-12 years. It is one of the oldest in Europe. Phew, even Greece has newer cars than we do!

We’re really not that poor, it’s just that the taxes are so high in here that everything costs a small fortune. That’s why many choose to drive a used car as it is better value for your money.

Average car ages on some of the European countries:
http://www.autoalantiedotuskeskus.fi/en/..._countries_2010

Surprisingly it seems that the average age of cars is quite the same in USA also, in the 11-12 years range. Could it be that the cars outside of the Salt Belt area are driven "forever"?
http://www.businessinsider.com/the-avera...ars-2014-6?IR=T

In Finland we have an obligation to use winter tires (with spikes i.e. stud tires or softer “high friction” tires i.e. studless snow tires) at winter. I think that could lead to less use of salt on the roads (compared to the Salt Belt in USA), as everybody can manage through icy roads without bigger problems anyway.

I think back in the 70s and 80s the cars suffered much more about rust. It was a well known fact that for Toyotas the engine would last forever, but the car body would “vaporize away in the form of rust” within 10-15 years

I think galvanized steel and improved factory made rustproofing found in many cars today helps a lot against rust. For example my Primera is now 9 years old and there's almost none rust on the visible parts of the car. And only some minor rust can be found at underneath of the car.

My personal guess would be that the cars last here at least 10+ years without bigger rust problems and maybe at 15+ years you have to start doing some minor rust repairs. But of course it depends a lot on the vehicle make, model and year.


Wish more people would use snow tires here! Salt kills the cars around here...

 

[finmile]

Originally Posted By: Urshurak776
This thread topic is one of the biggest can of worms I have ever seen.....


Ha ha. I guess there's a thin line between bravery and stupidity.

Well, maybe I can turn this to a success story by stating that the list was good but the title was bad. It should have been: "Top 8 myths about engine wear". How about that

Anyway, while the result was a bit surprise to me, I'm happy that we now have this kind of list of myths under one thread.