Cold Weather Short Trip Driving

I go from 17-18, maybe 19mpg if I can keep my foot out of it in the summer to 14-15… short trips don’t help, nor does colder denser air which not only requires a bit more fuel to remain relatively stoichiometric but also requires more energy to push through.
 
Yesterday I drove about 100 miles, much on the freeway, and the car felt sluggish. I was getting concerned that it might need some work ... plugs, pcv valve, or some such. But this morning I realized that the last oil change was with M1 EP HM 5W-30, the thickest oil that's been in the car since I've owned it. In the past, the oil's been M1 EP mixed 0W-20 & 5W-30, providing a substantially lower viscosity. Can't help but think that the heavier oil may be contributing to the sluggishness and poor mileage.

I'm tempted to drain out the HM and replenish with some 0W-20 EP and regular 5W-30 EP, both of which I have on hand. It's a waste of good oil, but I hate the way the car is performing, and I'd like to see if it's the heavier oil that's contributing to or causing the poor performance.
 
Yesterday I drove about 100 miles, much on the freeway, and the car felt sluggish. I was getting concerned that it might need some work ... plugs, pcv valve, or some such. But this morning I realized that the last oil change was with M1 EP HM 5W-30, the thickest oil that's been in the car since I've owned it. In the past, the oil's been M1 EP mixed 0W-20 & 5W-30, providing a substantially lower viscosity. Can't help but think that the heavier oil may be contributing to the sluggishness and poor mileage.

I'm tempted to drain out the HM and replenish with some 0W-20 EP and regular 5W-30 EP, both of which I have on hand. It's a waste of good oil, but I hate the way the car is performing, and I'd like to see if it's the heavier oil that's contributing to or causing the poor performance.
I have an 09 Camry the the dealer I bought it from put 5w-30 in, and did a full 5 quarts. I just changed it to 0w-20 full synthetic and I swear it idles better with less vibration and seems more quiet. ( these engines have a high number of complaints for vibration at idle).

I’m partway through my first tank of gas on this oil. It’s December in IA, so some mornings are in the 20’s and others in the high 30’s.

I’ll let you know what I’m seeing for mileage on this tank, but I think 5w-30 isn’t it’s happy oil weight.
 
I have an 09 Camry the the dealer I bought it from put 5w-30 in, and did a full 5 quarts. I just changed it to 0w-20 full synthetic and I swear it idles better with less vibration and seems more quiet. ( these engines have a high number of complaints for vibration at idle).

I’m partway through my first tank of gas on this oil. It’s December in IA, so some mornings are in the 20’s and others in the high 30’s.

I’ll let you know what I’m seeing for mileage on this tank, but I think 5w-30 isn’t it’s happy oil weight.
The vis @ 100deg for the 5W-30 HM is 11.8 vs 10.6 for the regular EP, mix the regular EP 0W-20 @ 8.6 as I have been doing and the result, however you choose to calculate it, is a bit thinner. Maybe that little 4-cyl prefers it that way. I'd love to hear your findings.
 
Filled up the Camry this morning and, sad to say, got the worst mileage EVER with this car. I averaged 17.8 mpg compared to the usual 21-22 mpg around town. The difference was that there was absolutely no freeway driving, the weather for the last month has been cold-ish, and all my trips were short ... nothing over 6 miles.

Many here will be familiar with this type of situation, but I mention it because there are also many folks who are concerned when their mileage drops during the colder months, or their driving style changes to encompass more short trips. I believe there may also be "winter gas" here in California that also has a deleterious effect on mileage.

Although I'm no novice to this situation, I was a bit surprised to the extent of the mileage drop.
Dont forget too that cold air is more dense than warm air, so when its cold out the engine has to richen up the mixture to keep it from being too lean.
The milage on my Accord normally goes from 38-40 during the summer months down to about 34-36 during the winter months. I never really worry about it because colder air, cold starts, cold temps that make it take longer for engine to warm up and winter fuel all hurt the milage.
 
Our Buick averages 32mpg (U.S. gallon) on the highway, through most of the year. I was dismayed on a highway trip a couple of years ago during a -38 deg C cold snap to see the mileage drop to 21mpg.
 
This is another long thread about something that is widely known and recognized as fact. Short trips and colder weather will drop your mileage. Not much else to discuss. I got more news for you, if it gets really cold, like below 0, it will have an even more drastic change in mileage.
 
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This is another long thread about something that is widely known and recognized as fact. Short trips and colder weather will drop your mileage. Not much else to discuss. I got more news for you, if it gets really cold, like below 0, it will have an even more drastic change in mileage.
Thanks for that update ... it's folks like you who keep the conversations relevant and on track. (y)
 
Yesterday I drove about 100 miles, much on the freeway, and the car felt sluggish. I was getting concerned that it might need some work ... plugs, pcv valve, or some such. But this morning I realized that the last oil change was with M1 EP HM 5W-30, the thickest oil that's been in the car since I've owned it. In the past, the oil's been M1 EP mixed 0W-20 & 5W-30, providing a substantially lower viscosity. Can't help but think that the heavier oil may be contributing to the sluggishness and poor mileage.

I'm tempted to drain out the HM and replenish with some 0W-20 EP and regular 5W-30 EP, both of which I have on hand. It's a waste of good oil, but I hate the way the car is performing, and I'd like to see if it's the heavier oil that's contributing to or causing the poor performance.
Lol
 
I should try 0W20 in mine again, I had switched to 5W30 some time ago, worries about the timing chain. I didn’t drive it at the time though. Maybe it’ll perk up, that’d be nice. :) mpg has been low lately, trying to get my scanguage calibrated for real time mpg. But I just swapped on snows and my idea of a nice cruising speed is not what is posted.
 
while working in State College Pa a fellow worker noted his older early 2000 model VW Diesel station wagon was ONLY getting 45 mpg in the cold single to teen range + said on the highway in the summer he gets close to 60 MPG!!!! i was happy with the 30 my hotrodded 1.8T 2001 jetta was returning with 4 guys in it!!!
 
I have had a few 5F starts and 7 miles round trip drives. My 2015 Pilot LX AWD manages 17 MPG in these conditions. Although optimal is only 19 MPG in short trip.
 
Yeah, I definitely notice a Mileage drop when the temperatures drop below 35 degrees, and especially if I’m doing short trips. The combination of winter gas, and the computer adjusting to air being more dense adds to fuel mileage dropping. But as soon as the temps creep back up my mileage goes back up too. Short trips don’t help either, as the cold starts lead to more fuel dumping in those cylinders.
The biggest issue is that the vehicle stays in open loop because the engine never gets up to temp to go into closed loop. The colder the outside temp the longer it takes, so if you short trip you mpg will def go down.
 
The biggest issue is that the vehicle stays in open loop because the engine never gets up to temp to go into closed loop. The colder the outside temp the longer it takes, so if you short trip you mpg will def go down.
Even in an arctic environment it doesn't take that long to get to closed loop with modern heated O2 sensors, etc.
 
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