Engine warm up

[jeffbrx]

if you have a device capable of monitoring obd2 values you will see the truck starts feeding in knock octane modifier at 3 bars of coolant temp. it takes a good while idling in cold weather to get there but when you start driving with low to moderate throttle input it warms up within 2 to 3 minutes.

Not being a mechanic I was wondering what OBD2 values refer to. Broaden my knowledge.

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[Master Blaster]

According to everything I read you just want to get the oil into the turbo, and when parking you want to let the vehicle idle for a few to cool down. Never floor the vehicle cold.

Cooling down the turbo is only useful on an air-cooled turbo. The Mav turbo is water-cooled, and will not get red-hot.

 

[Jah.]

It's the oil that is life blood of turbo as well of engine .

 

[Master Blaster]

if you have a device capable of monitoring obd2 values you will see the truck starts feeding in knock octane modifier at 3 bars of coolant temp. it takes a good while idling in cold weather to get there but when you start driving with low to moderate throttle input it warms up within 2 to 3 minutes.

Where is the filler to add "knock octane modifier"? Are you referring to cam phaser and ignition retard timing that use both knock sensors as one of the inputs? Since knock sensing has little to do with coolant temperature, I'm mystified.

 

[Tbone289]

if you have a device capable of monitoring obd2 values you will see the truck starts feeding in knock octane modifier at 3 bars of coolant temp. it takes a good while idling in cold weather to get there but when you start driving with low to moderate throttle input it warms up within 2 to 3 minutes.

That's one sign of the ECM transitioning from "open loop" to "closed loop" operation. This is what I mentioned earlier, that it's best to get to closed loop more quickly from driving rather than idling to reduce time running on a rich mixture. People tend to blame winter-blend gasoline for their reduced efficiency in cold weather, but I think they may not realize or consider the effect that warm-up and especially the richer mixture at warm-up has.

 

[Blue_Max]

Not being a mechanic I was wondering what OBD2 values refer to. Broaden my knowledge.

OBD2 = onboard diagnostics, second generation.

You can get a scanner to read codes (typically error codes) from your vehicle, but they can check other stuff, too. I recently got this one for a different vehicle of mine that was showing "CHECK ENGINE."
https://www.amazon.com/dp/B071FSNL73?ref=ppx_yo2ov_dt_b_fed_asin_title

 

[Tbone289]

Cooling down the turbo is only useful on an air-cooled turbo. The Mav turbo is water-cooled, and will not get red-hot.

Residual heat still flows into the turbocharger after engine shutdown, when water is no longer being actively pumped through the turbine housing. Cooling down a water-cooled turbo isn't as crucial as with an oil-cooled turbo, and isn't required with normal driving, but it's still good practice after a session of hard driving.

 

[Dad]

every handbook I've read says that warming up is not required.

It used to have value on some carbureted vehicles, and for the choke.

modernly, once the oil is everywhere, you're good to go.

oh, and if you're in a factory fuel injected chevy from the 50s, it needs a while. A long while!

I think it's more about getting the interior to a comfortable temperature in either hot or cold weather. Our Palisade has remote start with summer or winter settings and it just makes the drive a lot more bearable.

 

[Master Blaster]

I think it's more about getting the interior to a comfortable temperature in either hot or cold weather. Our Palisade has remote start with summer or winter settings and it just makes the drive a lot more bearable.

If warming up the interior in winter, the heated steering wheel, seats, mirrors and front window are a lot more efficient and require no engine-destroying idling time.
If cooling down in summer, what's wrong with opening the windows? I leave the back slider open in summer just to keep the temperature in the vehicle down.

 

[colinl]

Residual heat still flows into the turbocharger after engine shutdown, when water is no longer being actively pumped through the turbine housing. Cooling down a water-cooled turbo isn't as crucial as with an oil-cooled turbo, and isn't required with normal driving, but it's still good practice after a session of hard driving.

yes to all that. and this is exactly why autostop can do more harm than good for a turbocharged engine. little to no benefit in mpg unless you're stuck in gridlock (and I never am), and you might coke the turbo center section bearings.

 

[dochawk]

I think it's more about getting the interior to a comfortable temperature in either hot or cold weather.

The advice to warm up the engine comes from a day when heaters were optional even on Cadillacs, and before you could order anything other than wind to cool the interior . . .

 

[Ozarkbeard]

...If cooling down in summer, what's wrong with opening the windows?...

Dust, dirt ,pollen, fumes, insects, humidity.. And if driving while the windows are down, NOISE.

If it's cold in the truck, I turn on the heat. If it's hot, I turn on the air.

Get Ceramic window film installed on the windows if you want to keep the radiant heat out in summer (and keep it in, in winter). It makes a huge difference. And you don't have to get the darkest tint for the IR-rejection benefit.

 

[HeyBales]

Modern engines do not require to be warmed up. In the winter I give mine about a minute at 0 f (18 to -20 c), then we are gently off. I will drive it easy for the first few minutes while the internals (and tranny) are getting up to operating temp. The worst thing you can do in the winter is to repeatedly let an engine idle while cold then take it for a short drive (few minutes and shut it off) on a daily basis. The oil needs to get up to full operating temp to burn off the containments. The reverse is the same, do not drive an engine at a high throttle setting right before turning it off. (This last part would cook the turbo's bearings back in the day).

Good reminder on the tranny - I've seen so many that are concerned with warming up the engine, then proceed to take off in a hurry and you can hear the cold tranny not sounding great even from next door.

Some seconds engine rotation - gentle take off to get the tranny warmed up too.

 

[HeyBales]

Not being a mechanic I was wondering what OBD2 values refer to. Broaden my knowledge.

The vehicle's many computers (modules) are accessible through a serial port called OnBoard Diagnostics rev 2, that gives access to their network.

Some devices/apps that can communicate with them will allow looking at the same figures/values they are looking at. Besides the already mentioned error codes that turns on your check engine lite.

So you can look at the Parameter ID's (PIDs) for all sorts of things - engine temp, coolant temp, oil pressure, air flow, ect.

Now Google AI with a few good search terms can tell you all about it.

 

[Dad]

If warming up the interior in winter, the heated steering wheel, seats, mirrors and front window are a lot more efficient and require no engine-destroying idling time.
If cooling down in summer, what's wrong with opening the windows? I leave the back slider open in summer just to keep the temperature in the vehicle down.

Perhaps.
In the case of my hybrid Maverick, it's only the electric motor that's running. For the gas powered vehicles, I'm of the understanding that the engine needs to be on in order for those conveniences to work. Here in SoCal, the weather is much milder, so we're mostly content with using the heated steering wheel and seats in the winter. Rarely use the heater. Summers can be hot and it's nice

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