Dramatic drop in FE. A few questions...

[LincolnW]

Hey there,

It's been a while since I've posted and it's good to come back and see this site really developing! Nice job!

Anyways, so I got a new job where I take a train to work, and I only have to drive 2 miles to and from the park & ride each day. I went from driving about 45 miles a day, to driving 4 miles a day. Wahooo!!!!!!

The thing is, my FE seems to have gone way down. I haven't had to fill up for over a month now, but I have only gone 200 miles on this tank and I'm almost at E.

I think this is happening for a few reasons:

- It's been cold out, and I usually let the car warm up for 2-3 minutes in the morning and in the evening before I drive it.
- The car never really gets fully warm during the 2 mile drive to the park & ride.
- The 2 mile drive to and from the park & ride is low speed, through a neighborhood and through a few stop lights, I am under 40 mph the whole trip.

Could those reasons alone be enough to decrease my fuel mileage from 36+ to more like 20? I'm not really complaining since I went from filling up once a week to less than once a month, but I still am a bit perplexed at this dramatic decrease in fuel efficiency.

What do you think?

[zpiloto]

I think all of the above is correct. The shorter the commute the worst the FE. Why idle the car for 3 minutes? You get 0 MPG's when you're idling. Just let it warm up as you drive "low speed" through the neighborhood. Also might want to change oil a lot more often since the car nevers warms up enough to get the moisture out. You could also try a Engine Block Heater for the first leg.

[rh77]

Short trips kill FE, BUT...

Using Park-and-Ride makes up for it. Since you're not getting kind of FE all the time, for long trips, then you may be stuck; however...

THe fuel savings with PnR more than make up for it -- good work there!

If you really want to improve the FE from the Home-to-Parking area, perhaps an Engine Block Heater would get you to closed-loop sooner and better FE.

RH77

[LincolnW]

So you don't think I should let it warm up at all?

It just makes me nervous because I don't know if I want to drive it before warm oil gets to the turbo. I'm not sure if I should be spinning the turbine before the bearings are good and lubed up with warm oil.

And a block heater is a great idea. I'll look into picking one up.

[rh77]

Originally Posted by 90CivicStandard

So you don't think I should let it warm up at all?

It just makes me nervous because I don't know if I want to drive it before warm oil gets to the turbo. I'm not sure if I should be spinning the turbine before the bearings are good and lubed up with warm oil.

And a block heater is a great idea. I'll look into picking one up.

Depending on how touchy your turbo is, you can gently drive without spooling-up the turbo too much and probably not wear the bearings beyond normal use. When I had my Evo, I would do just this (unless it was below 20F out, then the transmission fluid was so thick that it wouldn't shift, and letting the clutch out to idle nearly stalled it in Neutral). I assume this isn't your case

Since the turbo is a concern, something that also warms-up the oil may be a good option. (Not sure about the options here).

RH77

[zpiloto]

Originally Posted by 90CivicStandard

So you don't think I should let it warm up at all?

It just makes me nervous because I don't know if I want to drive it before warm oil gets to the turbo. I'm not sure if I should be spinning the turbine before the bearings are good and lubed up with warm oil.

And a block heater is a great idea. I'll look into picking one up.

I'll let theclencher reply to this. Clencher?

[Peakster]

Originally Posted by theclencher

...but in my case I start the engine and go right off, but will idle down the block in low gear, no throttle, in the winter. In the summer I'm less gentle. When I can feel warm air coming out of the defroster vent I'll grab another gear or two... most owner's manuals say right in there, start it and go. They oughtta know.

I always start and go too. Even when the temperatures linger around the -40 mark. I have a windshield washer fluid heater that melts the ice and frost off my window when it's squirted on and I also use "Anti-Fog" by Rain-X for the interior of the windows. All I need is stove and chinmny and I'd be set for heat too .

[skewbe]

Originally Posted by theclencher

mmmmmwha'?

This guy is a perfect candidate for a grille block and engine blanket.

I wonder if a block heater would use enough energy to transport a person 4 miles?

[rh77]

Even when the car was parked at the airport at close to 0-degF, I'd scrape, startup, and go. Granted the auto-trans doesn't want to work completely at first, but it moves...kinda.

...second gear kicks-in eventually.

Man did I need the blanket idea then -- of course no heat until the gauge is up to Norm-Temp.

The trick is to let the car move itself when cold. Use high-idle to move along in 1st, then shift to 2nd, etc. Before you know it, the gauge is moving.

RH77

[diamondlarry]

Many years ago, I drove my grandpa's '72 Matador wagon while my car was being worked on. It turned out to be one of those cars that would start when every other car in the neighborhood wouldn't. Back in '83, the temp was -22F on Christmas Eve morning and my brother had to go and do chores at grandpa's. His truck wouldn't start and he asked if I could take him. The car had been sitting more tha 8 hours so I told him I would if it will start. It started right up as though it had been running an hour earlier but, when I shifted into gear, it wouldn't move. That was one of the only times I've ever had to let a car warm up before I could drive it. A few years ago my '92 Gran Prix started and moved right away when it was ~-8F.