View Full Version : Average Warm-up Time?
theonew
01-27-2005, 03:35 PM
I recently got my first bimmer, a 1995 525I Touring, and though I have no empirical data to compare it with, my gut is telling me that the car is taking too long to heat up to full operating temperature. In the cold weather here in New York City (lets say about 32 degrees F.) I start the car, let it idle for a couple of minutes and then start driving. The temperature gauge doesn't hit the middle till about 15 or 20 minutes worth of non-highway speed driving, and only a little bit faster at highway speeds. Does this sound normal? My Toyota Camry heats up in less than half the time.
shogun
01-28-2005, 04:44 AM
Do not start the car and let it idle to warm up. Every owners manual says that.
Higher revs are good for immediate oil pressure and more oil circulation = less wear in the cold start phase. What I do: I start the car, rev it up just short to about 2000 RPM that the oil pressure is there, and then you should immy start driving with RPM's around 2.000- 2.500 RPM. That means that the oil is circulated faster, the engine is coming to working temperature and the coolant will come up to temp much faster.
Also the auto transmission will change to the next higher gear at a later stage when the car is not yet at temperature. You might have noticed this already.
That is also to get the cats fastest possible to the normal and required temperature.
20 minutes is by far too long. Depending on traffic it is maybe 2 miles if the street is free, but already before the needle will climb on the coolant gauge.
I think your thermostat is always fully open/stuck. No other possibility.
Change that and you will have a nice temp very quick.
theonew
01-28-2005, 06:42 PM
Thanks for your response. I'll replace the thermostat. I do actually do most of what you said, I only let my car warm up for a couple of minutes before driving gently, but I didn't now that its better to raise the revs in the beginning. Thanks for the tip and info.
Paul in NZ
01-28-2005, 09:00 PM
even couple of minutes is a waste of time and fuel,drive it as soon as it is driveable.I go after the si lights go off
My usual warm up practice is to start the car and let it git fluids moving while I hook up the seat belt. Once I'm hooked in, we're ready to go.
I did wonder why the auto trans seemed to shift at a higher rpm when cold. Thanks for the info. I'll adjust the driving of my car with a manual trans to do the same -- I usually baby it till the temp gage is out of the blue.
When it is very cold, say below about 10 or 15 degrees F. I usually do let the car idle for a couple minutes, but put the auto tranny in drive while buckling up, turning on radio, taking sip of coffee, etc. After these couple of minutes, then I will move forward or back out in reverse or whatever, driving easy until it warms up. I have noticed that when very cold it does take awhile to warm up, but I do hear the aux pump or the stepper motors working within minutes delivering whatever warmed up coolant is available to the heater core and providing some cabin heat. I would say it only takes about 5 minutes to significantly move the temp guage needle.
Qsilver7
01-29-2005, 12:03 PM
After reading your post Thursday...I thought I'd pay attention Friday morning...and this is what I got. When I pulled my 95 525iT out of the garage Friday morning, it was -1 degree Fahrenheit...after 5 minutes (damn kids & school buses) and 3 miles down the road...the temp needle had moved out of the blue and was heading past the next hash mark toward the center. Thank God, the person, and the parents of whoever invented heated seat! OOHHH how I love those bun warmers...they make days like this tolerable!!! :D
I must add that iniside the garage it's usually about 20 degrees warmer than it is outdoors...but that still makes it below freezing (32 degrees Fahrenheit for our Celcius brethren). Brrrrrr! :D
WarrenBrown
01-29-2005, 01:40 PM
The original housing is plastic and tends to crack with age.
Bimmerparts $23.99 their # DBD8902D8FS9SH (bimmerparts.com). BMA (bmaautoparts.com) might also carry them.
The original water pumps were of a plastic impeller design, they also tend to fail before around 100K, some sooner and some later. Not a bad idea to replace at the same time. Look for one with a metal impeller, other folks have recommended Graf brand.
Warren
91 318is
95 525iT
Powered by vBulletin® Version 4.2.3 Copyright © 2024 vBulletin Solutions, Inc. All rights reserved.