My car feels disturbingly good...

[poly_poly-man]

I'm up here in rochester, where one would say it got cold, despite it being one of the mildest winters on record. I drove around a lot in this cold weather, and I've been getting a reputation as a rough driver - bad on the clutch, transmission, not smooth, etc. I thought it could have been my skills deteriorating or smth, so I shook it off. The one thing that was harder to shake off is the drastic loss of mileage - I usually get 22-24, even in the winter it's more like 20-22 usually, but this winter I've been seeing numbers closer to 17mpg, and I don't idle for long or take it hard. No matter what, though, the car felt a little ragged, rough around the edges. It's been tougher to handle in terms of driver input, it likes to do that engine brake jerk in 1st and 2nd, the PS pulley squeeks when I put too much load on it with my steering wheel, etc.

Today, we hit 65* as a high, and it never got below about 50*. I did two quick runs in my car - one to pick up a couch a little ways down the road (it went on the roof. With a tow strap. And it was only me and one guy helping), and one to drop a girl from my floor off at the bus station in the actual city. Both times I noticed the little things, like the fact that the clutch felt MUCH nicer, the accelerator pedal and acceleration in general felt smoother, the engine brake jerk was completely gone - I was even complemented on how smoothly I drove (from someone who had never ridden with me before). I can't really pin down everything that changed, but I will definitely say it was a nicer, more fun experience - the comparative I would use is definitely smoother.

So, what am I doing wrong for winter? Are all of my fluids just acting like they are totally not within correct temperature range? Why?

[Anub1s]

Could be that your not-so-protune isn't accounting for temperature properly. There are certain tables within the map that compensate for differing temperatures. If they're not set up properly, you can have wild variations in fueling and timing. They aren't a perfect science, but if they're set up completely wrong, it could cause some drivability as well as fuel mileage issues.

One thing is that winter is never easy on a car. Though the engines enjoy the cooler air, everything else stiffens up and hardens when it's colder. Clutch wise, I have no idea though.

[poly_poly-man]

That's a very valid point - I'll have to do a few log pulls when the temperature drops again (Good thing it'll snow again tomorrow :P )

I feel like a lot of these issues are strictly mechanical - I notice that just about all of my problems are directly related to something that either lives in oil (trans/diffs) or is hydraulic (PS pump, clutch), and it really does feel like a problem with those fluids sometimes.

I will take a look to see if I screwed something up in the tune for winter driving, but what can I do about all of these mechanical problems? Or will some of them magically go away?

[EJ257]

Have you ever tweaked the compensation tables?

[Mikie13]

Maybe its time to do fluid changes?

My car is running 100x better since I did the tranny fluid and rear diff fluid. Shifting has been smooth as butter on 105k miles now, and that's through 30s on up to the 70s (today).

[poly_poly-man]

Maybe its time to do fluid changes?

My car is running 100x better since I did the tranny fluid and rear diff fluid. Shifting has been smooth as butter on 105k miles now, and that's through 30s on up to the 70s (today).

The only fluid I might be worried about is oil - I'm going to change it next time I'm home (still well within a valid OCI). I did the rear diff and tranny fluid relatively recently (within less than 10k miles), and I'm not sure if my uncles did a complete change during the clutch job. The hydraulics I can see look like the right color and are at good levels, not sure on the last flush (although I'll assume they did something with the clutch fluid during the clutch job). Are there alternative fluids for these things that might work a little better in the cold?

And no, I've not touched temperature or pressure compensation - should I?