improving cold start FE [throwing around ideas]

[mjo]

If you don't have a garage you can't use the electric heater. Would anyone attempt a small homemade kerosene lamp under the oil pan?

[lunarhighway]

would there be any gains from a reflective inner hood surface or another kind of insulation? recently while checking out in house energy saving tips i came around the sugestion of placing reflective shields behind heating radiators. perhaps simply painting the inner surface white or silver might make a small differense?

my car sleeps outside to my winter FE is considerably lower

[DRW]

landspeed wrote:"If you get a wideband lambda sensor, you may find a certain throttle position that puts the mixture to 14.0:1 even when cold - my car does this, and it is better than flooring it (10.0:1), or driving along very gently (10.0:1 ratio). Driving with the right load can help the economy a lot by avoiding wastage of fuel."

I've noticed the same thing. I've also read in the ecu disassembly for my car that cold enrichment is reduced as airflow levels increase. I imagine this is a characteristic of the needs of a cold engine, and similar to other modern computer controlled fuel injected engines. I tried leaning out the cold enrichment settings, but the motor doesn't run as well at light throttle. So I've adjusted my driving style to suit. When I'm driving with a cold engine I'll accellerate briskly in the stoich range in between light throttle/cold enrichment and heavy throttle/accelleration enrichment. I get up to speed quickly, then shut the motor off and coast. This way I avoid high idle speeds at rich settings, which wastes more gas than if the engine was warmed up.

Since I park on the street, I try to find a spot on the side of the street that gets sunshine earliest. Coincidentally that side of the street lets the engine face the sun, too. It might add an extra 5 or 10 degrees at most.

[landspeed]

I live in a rural area, so security is not much of an issue. When my block heater was broken, on a sunny morning, I would open the bonnet, and let the sun shine on the engine! It made the engine go from 'stone cold' to the touch, to 'luke warm' to the touch, and I'm sure it help economy too.

Just dont do what I did - let a tiny bit of water get into the electronics of your block heater. I just managed to blow a hole through 3mm of Aluminium plating (part of the block heater container) in a split second - impressive!. I have now dried it off completely, and checked it, and it still seems to work. I don't trust it as much now though .

For those without a rad block, a rad block (especially at the top of the radiator air vents) will make a difference - as a lot of hot air will convect from here when parked (or when using a block heater etc), and if you reduce the convection air flow (drawing in cold air underneath the engine, and letting hot air out through the top), the engine will cool more slowly.

I'm now going to see if it works for longer (fire extinguisher at the ready) :O

[landspeed]

Originally Posted by mjo

If you don't have a garage you can't use the electric heater. Would anyone attempt a small homemade kerosene lamp under the oil pan?

People did use to have oil pan heaters, and it should make a difference! I guess the important things are to ensure the flame itself is shielded, so only hot air goes towards the oil pan, also ensuring that it isn't giving off too much heat to boil / char the oil in the oil pan, and parking your car away from other cars, buildings, just in case the worst happens (and having a fire extinguisher to hand).

I suppose you would have to check carefully for minor fuel leaks from the engine bay fuel lines too - or these could cause a disaster!

[Erdrick]

I think I am going to take landspeed's advice. I can't keep my hood open in my neighborhood, but when I am school that should work great. I park with the sun coming in through the windshield, which heats up the car interior.

So, by propping open my hood, it will both a) heat up my engine with passive solar heat and b) keep my cabin from getting too hot while the car sits in the sun.

Hope to see some improvements, but I have no SG II (can't be used in a Japanese domestic car) so I can only rely on fill-up to fill-up. Pretty much all stations in Japan are full-serve too, so I can't control how much fuel I get at fill-up time either. Man.. there is no way I can gauge whether I get any benefits out of this method. Oh well...

[landspeed]

Get a SuperMID Look at my gaslog - there was a gradual increase, the next 'jump' (quite major) was the competition, and the next 'jump' after that was the SuperMID! With SuperMID, I am getting 20% better economy straight away! Should be easy to get, as you are in Japan, and it has loads of info (and, actually, seems to be more accurate than the ScanGauge, which seems to have some inaccuracy, I think when it in fuel cut mode or something?)

By the way, I only prop up the hood, outside my house, which is down a 3/4 mile dirt road - don't leave it unattended for more than a few minutes - you don't want anyone messing it up!.

Edit - I see that it is your company's car, so maybe you can't fit a SuperMID. Are you sure the car doesn't have an OBD-II gauge somewhere?

[skewbe]

I've always been a little concerned about the additional energy costs of heaters and I don't know how many are left plugged in all night and how many are on timers so they don't waste more energy than necessary.

Having said that, I have heard that some hybrids pump coolant into a large "thermos" (like 3 gallons) when the engine shuts down. I imagine a fitting could be made to a well insulated bottle sitting in the garage (or trunk) that stores hot fluids when appropriate (might be worth doing the gallon of oil in the engine block and the tranny too).

[diamondlarry]

Originally Posted by skewbe

I've always been a little concerned about the additional energy costs of heaters and I don't know how many are left plugged in all night and how many are on timers so they don't waste more energy than necessary.

Having said that, I have heard that some hybrids pump coolant into a large "thermos" (like 3 gallons) when the engine shuts down. I imagine a fitting could be made to a well insulated bottle sitting in the garage (or trunk) that stores hot fluids when appropriate (might be worth doing the gallon of oil in the engine block and the tranny too).

The block heater in my Prius is 400W. I have it on a timer that is set to come on ~4 hours before I'm going to go anywhere. At ~$.10/KWH that would be ~$.16 and the gas saved is significantly more than the cost of running the EBH.

As for the "thermos," it is only 3 quarts instead of 3 gallons and it only keeps it "warm." In fact, when I start out in the morning after unplugging the EBH(when I don't forget to un-plug it -another story), the coolant temp will actually decrease(from ~140F down to ~125F or lower) slightly for a few seconds when the "thermos" empties into the system. I end up being up to the temperature at which I have full use of the hybrid features(~155-160F) within 1/4 mile of my house and usually to the full 190F within 1/2 mile. Without the EBH it took nearly 1 mile longer to reach the above mentioned levels.

[rh77]

Originally Posted by diamondlarry

The block heater in my Prius is 400W. I have it on a timer that is set to come on ~4 hours before I'm going to go anywhere. At ~$.10/KWH that would be ~$.16 and the gas saved is significantly more than the cost of running the EBH.

That's why I implement the same. For the average workday, I have it set on a cheapo timer from the hardware store, to begin heating about 3 hours before departure. For me, cold-start emissions and fuel consumption on a 10 year-old vehicle is significant -- much less is emitted, more $ and fuel is saved by using the power grid to warm the car.

Simple timing tests with the SG show a significantly quicker time to Closed-Loop operation -- so you know it works.

(when I don't forget to un-plug it -another story)

Yeah, same here -- it just pulls loose, but now it's in the path of parking later-on -- can't roll in under zero-power, have to stop, etc.

For me, it's remembering to plug it in after driving in 90-degree weather, for the next morning...

Which is another point -- even if it's warm outside, block-heating still helps get that coolant temp up to the most efficient temperature range (190-210F in my case). It's still a 100-degree difference, which takes energy (fuel or grid), to get to.

RH77