Shutting off the engine before oil is up to temp

[Subliminal]

I live in a fairly small city where everything is within a 5 minute drive. I've heard before that it's bad for our DI engines to shut off the car before the oil is fully warmed up so I usually drive around until its warm and then park it... if it's something thats only going to take a minute I just let the car idle instead of turning off and then right back on. But I've always wondered if it's actually necessary for me to do all this?

I tried searching but everything I've found is discussing whether or not to let it idle warm-up before driving off.

 

[VL3X]

I've never heard this before. What does direct injection (I assume this is what DI means) have to do with oil temps? If anything, I remember back in the turbo timer days, that you'd want to let the car to "cool off" for a minute or two after boosting as not to gum up the turbo. My daily work commute is only about 8 minutes one-way, so my oil temps barely get up to 180 before I park. If anything, I'd say running your car for only a short time simply has a negative effect on fuel economy, but your alternative of driving extra to warm it up invalidates that anyway.

 

[Subliminal]

I couldn't remember where I heard it before but I just found it now, it's from a comment on one of ShopDaps videos ( Carbon Build up on Direct Injection Engine (Intake Valves) AKA GDI Gasoline Direct Inection )

If you had a catch can installed on the PCV line, you would understand why short distance drives or cold weather will increase the buildup on the intake. The key to decreasing buildup is high temperature. Coolant temps rise rapidly in modern engines, but oil temps take extended drive time to get to operating temp. When you shut off an engine before oil temps are at around 200F, then you will see excess condensation and buildup on the intake manifold and valves. You can verify this if you already have a catch can installed.

Experiment... Empty the catch can and then drive consecutive 50 miles on the highway. Check the catch can, it will probably have a few drops oil if any at all. Next experiment, drive 5 miles and let the car cool down. Do this 10 times and you will have driven 50 miles again. Inspect the catch can this time and it will be full of water and oil deposits. This is what is getting on the intake. Constant short distance driving will age a motor much faster than "spirited driving."

 

[Tsi7]

It's bad because the oil doesn't get up to temp so the condensation that may form doesn't get burnt off (evaporated) , thus potentially diluting/contaminating the oil and causing it to lose it's properties faster then usual.... solution, change your oil sooner.

However, only way of knowing that your oil is contaminated with water is by doing a used oil analysis. Given that you're in Cali where it's hot all year round, I wouldn't be as concerned doing short trips

Here's some more forum reading for you

https://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2860236

Also, it has nothing to do with DI engines, it can happen to anything that runs on some form of oil

 

[Subliminal]

It's bad because the oil doesn't get up to temp so the condensation that may form doesn't get burnt off (evaporated) , thus potentially diluting/contaminating the oil and causing it to lose it's properties faster then usual.... solution, change your oil sooner.

However, only way of knowing that your oil is contaminated with water is by doing a used oil analysis. Given that you're in Cali where it's hot all year round, I wouldn't be as concerned doing short trips since it's hot there all the time

Here's some more forum reading for you

https://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2860236

Also, it has nothing to do with DI engines, it can happen to anything that runs on some form of oil

That's good to know, plus I already change the oil every 5k.

 

[Tsi7]

That's good to know, plus I already change the oil every 5k.

If you're driving around 10k a year then that's ok, however some will tell you that 5k is quite early. Now if you're only driving 5k a year that's a different story

There is some data out there that actually shows doing your oil changes too often is a bad thing

https://www.efficientplantmag.com/2008/07/how-clean-is-the-new-oil-in-your-equipment/

 

[Subliminal]

If you're driving around 10k a year then that's ok, however some will tell you that 5k is quite early. Now if you're only driving 5k a year that's a different story

There is some data out there that actually shows doing your oil changes too often is a bad thing

https://www.efficientplantmag.com/2008/07/how-clean-is-the-new-oil-in-your-equipment/

I drive about 12k miles a year. Is it true oil should be changed more often when tuned?

 

[VL3X]

I drive about 12k miles a year. Is it true oil should be changed more often when tuned?

Assuming the car will be driven harder when tuned, yes. Though don't think you need to change it every 3k, unless you're tracking it every weekend.

Dealer recommends every 10k. I like to do it around 7k, or much earlier if there's a track day or two in there.

 

[Golfs everyday]

One of the reasons why I never start my car during hibernation is I would need to drive at least 15-20 min to get the oil up to temp 180F+ and dry the mid pipe of vapor before putting the car away. By that time the car would be caked with road salt.

 

[adam1991]

I'd be more worried about water in the exhaust.

Short trips will kill a car. There's no way around it. It's the cost of doing business. Accept it. And honestly, in this day and age, simply get an electric car for that type of work--you avoid all the problems that kill an ICE car.

I just bought an 05 Toyota Matrix (Corolla wagon, really) with 240K on it. That's 17K/year. Thing looks and drives like new. I have a buddy who took his 96 Corolla for 450K miles, driving it quite a bit, and it was still on original engine and transmission--so I have faith that it will last long enough to suit my purpose.

 

[Wrath And Tears]

If you're driving around 10k a year then that's ok, however some will tell you that 5k is quite early. Now if you're only driving 5k a year that's a different story

There is some data out there that actually shows doing your oil changes too often is a bad thing

https://www.efficientplantmag.com/2008/07/how-clean-is-the-new-oil-in-your-equipment/

Did you link the wrong article by chance? That article is about how oil gets dirty during transport and bottling. Not about how early oil changes harm an ICE.

 

[Subliminal]

I'd be more worried about water in the exhaust.

Short trips will kill a car. There's no way around it. It's the cost of doing business. Accept it. And honestly, in this day and age, simply get an electric car for that type of work--you avoid all the problems that kill an ICE car.

I just bought an 05 Toyota Matrix (Corolla wagon, really) with 240K on it. That's 17K/year. Thing looks and drives like new. I have a buddy who took his 96 Corolla for 450K miles, driving it quite a bit, and it was still on original engine and transmission--so I have faith that it will last long enough to suit my purpose.

I would love a used EV but I wouldn't be able to charge it in my apartment parking lot and I haven't seen any chargers around town either. Been thinking about a small used truck

 

[Golfs everyday]

My buddy who lives in Burbank, CA commutes via his road bike and uses the bus on crummy days. Maybe get a folding bike? Easy to carry inside the apartment or office.

 

[Subliminal]

My buddy who lives in Burbank, CA commutes via his road bike and uses the bus on crummy days. Maybe get a folding bike? Easy to carry inside the apartment or office.

I hadn't seen folding bikes before, pretty cool

 

[adam1991]

I would love a used EV but I wouldn't be able to charge it in my apartment parking lot and I haven't seen any chargers around town either. Been thinking about a small used truck

You are the case that the EV-heads love to ignore.

EVs are not for everyone, for any number of reasons. ICE isn't going anywhere soon.