Results 1 to 19 of 19

Thread: To idle or not to idle -- that is the question!

  1. #1
    Join Date
    Sep 2007
    Location
    SF Bay Area
    Posts
    548
    My Cars
    98 M3 vert, 05 X5

    To idle or not to idle -- that is the question!

    Hey Guys -- This is a general automotive question I thought might lead to a good debate.

    Is it better to idle/warmup your car or truck before driving, or simply start and go?

    My next door neighbor idles his brand-new diesel Ford pickup for at least 5 minutes before leaving early every morning. Being California, it's never cold, the noise is annoying, and often wakes us up. It's my understanding that neither new diesel, nor modern fuel-injected cars need any extended warmup, and in fact is hard on the engine over the long term, while wasting fuel. Gone are the days of warming up the carburetor!

    I start my M3 (or X5) and head right out. What say you all?

  2. #2
    Join Date
    Dec 2005
    Location
    Virginia
    Posts
    474
    My Cars
    1997 M3, 2012 C63
    There is nothing to debate as warming up a car before driving is not necessary for modern fuel injection engines. Get in a and drive gently until fully warm. Someone people remote start their cars to heat or cool the cabin, but that is a different thing.

  3. #3
    Join Date
    Aug 2013
    Location
    Seattle, WA
    Posts
    1,433
    My Cars
    1999 BMW M3 Coupe
    I know S52's have a tendency to be a bit grumpy when cold, easier to stall and so forth. However, as said above there's no harm in driving immediately as long as you aren't revving it really hard when cold. It takes a bit for oil to get to the right temperature/viscosity for optimal lubrication, so you should never do anything like bounce off the redline/limiter with a cold engine.

    So yeah, unless you are driving like a maniac "warming up" your car is just a waste of gas. Just be gentle until the engine temp reads somewhere above the blue.
    1999 M3/2/5 - Titanium Silver - Track/Weekend Toy


  4. #4
    Join Date
    Feb 2005
    Location
    Long Island, NY
    Posts
    6,479
    My Cars
    1995 M3 - 2007 X5
    I'm almost certain that its written in the owner's manual to not idle the car to warm it up before driving.

    I start the car, set my radio or bluetooth for some tunes and then get moving.

  5. #5
    MauiM3Mania's Avatar
    MauiM3Mania is offline Observer/Master Skeptic Moderator
    Join Date
    Jan 2002
    Location
    Central Pacific
    Posts
    10,809
    My Cars
    88M3 99M3 04M3 ITBx16
    Agreed with the 'start it and get on the road' approach.

    Quote Originally Posted by TostitoBandito View Post
    Just be gentle until the engine temp reads somewhere above the blue.
    I'm more conservative than some in that I wait until oil gets up to operating temp, 100C/212F before anything more than 'gentle' happens The time required to reach that point varies of course, but my oil temp gauges tell me it's a good five to ten minutes of driving.

    The factory water temp gauge is misleading and not a good guide for this purpose.
    04M3 TiAg 69k slick-top 3 pedal
    99M3 Cosmos 61k S50B32 euro 6Spd

    88M3 AW 43k miles Project FS


    WTB: 3.5" Eurosport/Conforti CAI

  6. #6
    Join Date
    Aug 2014
    Location
    Redwood Shores, CA
    Posts
    290
    My Cars
    1999 BMW M3 Coupe
    If you really wanted to warm it up, all you gotta do is let it idle till the revs drop a bit and then don’t do any hard driving until everything is up to temp. It shouldn’t take more than a minute for the revs to drop to proper idle RPM


    Sent from my iPhone using Tapatalk

  7. #7
    Join Date
    Jun 2009
    Location
    washington dc
    Posts
    8,679
    My Cars
    Avus Cosmos Calypso!
    Jump in and drive gently. Idling just wastes fuel and is bad for the environment because the engine takes much longer to get up to operating temperature.

    What's more annoying are the people who leave their vehicles idling while pumping gas or just stopped somewhere (but not at a stop light), because they think it's cool for some reason. Diesel is both more noxious and obnoxious for sure.

  8. #8
    Join Date
    Sep 2007
    Location
    SF Bay Area
    Posts
    548
    My Cars
    98 M3 vert, 05 X5
    I should print-out all your replies and stick them on my neighbor's windshield!!! That ought to start a feud!

  9. #9
    Join Date
    Nov 2002
    Location
    Westchester, NY
    Posts
    326

  10. #10
    MauiM3Mania's Avatar
    MauiM3Mania is offline Observer/Master Skeptic Moderator
    Join Date
    Jan 2002
    Location
    Central Pacific
    Posts
    10,809
    My Cars
    88M3 99M3 04M3 ITBx16
    I'm with the third reply, but he got banned. LOL
    04M3 TiAg 69k slick-top 3 pedal
    99M3 Cosmos 61k S50B32 euro 6Spd

    88M3 AW 43k miles Project FS


    WTB: 3.5" Eurosport/Conforti CAI

  11. #11
    Join Date
    Feb 2005
    Location
    Long Island, NY
    Posts
    6,479
    My Cars
    1995 M3 - 2007 X5
    Quote Originally Posted by MauiM3Mania View Post
    I'm with the third reply, but he got banned. LOL
    This was my favorite reply from that thread on fchat:

    a car left idling does not equal warming up

    start the car and drive her gently until all fluids are properly warmed up, not just the engine oil, and then let her rip.

  12. #12
    Join Date
    Aug 2013
    Location
    Seattle, WA
    Posts
    1,433
    My Cars
    1999 BMW M3 Coupe
    LOL.

    Give me a break Ferrari guys. Unless you're at a racetrack doing long stints there's no need to worry about transmission/diff fluid temperatures, and certainly not about it being too cold. Gear oil doesn't need to be pumped anywhere, and it will lubricate just as well when cold. The only thing which might change as it warms up is you might get slightly less driveline loss due to lower viscosity when it's hot.

    Oh, and make sure you get your brake fluid nice and hot too.
    1999 M3/2/5 - Titanium Silver - Track/Weekend Toy


  13. #13
    MauiM3Mania's Avatar
    MauiM3Mania is offline Observer/Master Skeptic Moderator
    Join Date
    Jan 2002
    Location
    Central Pacific
    Posts
    10,809
    My Cars
    88M3 99M3 04M3 ITBx16
    Quote Originally Posted by TostitoBandito View Post
    Oh, and make sure you get your brake fluid nice and hot too.
    Hey, this is important stuff. 214 posts important?
    04M3 TiAg 69k slick-top 3 pedal
    99M3 Cosmos 61k S50B32 euro 6Spd

    88M3 AW 43k miles Project FS


    WTB: 3.5" Eurosport/Conforti CAI

  14. #14
    NeilM is offline Member BMW E36 M3 Expert
    Join Date
    Mar 2007
    Location
    Fort Wayne, IN
    Posts
    5,016
    My Cars
    96 M3, 15 Golf R, 18 Q5
    Modern fuel injected cars use so little fuel to idle that it's a very ineffective way to warm up the engine anyway, even if it were needed. Plus idling in neutral doesn't work for the transmission, which also needs to warm up.

    Neil

  15. #15
    Join Date
    Jul 2011
    Location
    Austin, TX
    Posts
    2,181
    My Cars
    S54 E36 M3, E32 740il
    Quote Originally Posted by ChuckDizzle View Post
    I'm almost certain that its written in the owner's manual to not idle the car to warm it up before driving.

    I start the car, set my radio or bluetooth for some tunes and then get moving.
    It is indeed in the manual. Start driving immediately.

    As for the S52 lumpy-when-cold issue, I find it only happens when I DO let it sit and idle (on the odd occasion when something happens to stop me from leaving immediately). If I start driving, it doesn't happen.

    The problem is that idling places zero load on the engine. Cold oil, relatively little pressure, and near-zero load means it warms up much more slowly than if you'd just drive it.

    -Josh: 1998 S54 E36 M3/4/6 with most of the easy stuff and most of the hard stuff. At least twice. 271k miles. 1994 E32 740il with nothing but some MPars. 93k miles.

  16. #16
    Join Date
    Oct 2018
    Location
    Fishers, Indiana, USA
    Posts
    6
    My Cars
    1999 BMW M3
    As everyone has pointed out, not necessary with modern vehicle or even recommended. I feel like everyone has hit the nail on the head that you don't want to kiss the rev limiter or anything until it is up to temp (or really ever if you can avoid it), but you get the idea.

    I'm guessing you neighbor is one of those that doesn't care what the manual or anyone else has to say about it...he'll keep doing what he wants/knows.

    I'll take it one step further and suggest that a brand new diesel more than likely also has a Diesel Particulate Filter and EGR (Exhaust Gas recirculation) system installed, which can malfunction if the vehicle is left at idle for too long without and High Idle Controller added. The system does not work well at lower RPM's and if it is time for the system to operate and there is no load, it could cause problems. I'm not an expert on it by any means, but it is something you might want to look into and could bring up with the neighbor to have him re-evaluate his need to idle the truck. Normally a 5-10 minutes is not going to matter though...it becomes a problem when you get closer to an hour of idling with no load.

  17. #17
    RRSperry's Avatar
    RRSperry is offline Senior Moment Member BMW E36 M3 Expert
    Join Date
    Mar 2002
    Location
    Eldersburg, Md
    Posts
    12,368
    My Cars
    95 ///M3sc, '21 C8 HTC
    Wow, you mean you all don’t have oil and coolant preheaters like F1 cars? Lol


    just drive the car like a normal person until it’s blowing hot air... Then you can get all M3 owner on it...
    No matter where you go, there you are...

  18. #18
    Join Date
    Dec 2013
    Location
    Chicagoland area
    Posts
    4,372
    My Cars
    EXOTICS
    Tell your neighbor to keep his idling under 60 seconds,
    just about the time it takes to click and adjust the seatbelt, adjust your favorite tunes, check mirrors...etc.
    The amount of time needed is simply to insure complete fluid circulation, and keep revs in normal range,
    under about 3k~4k rpm until engine reaches proper operating temperature.

  19. #19
    Join Date
    Sep 2007
    Location
    SF Bay Area
    Posts
    548
    My Cars
    98 M3 vert, 05 X5
    I never would have guessed this topic would generate so much debate! Sounds like the consensus is, get in and drive, albeit slowly at first, whether it's a modern diesel or gas engine. That was my "educated guess" when I posted the thread, but it's funny how searches online will result in a wide range of opinions, especially concerning modern diesel engines. Some say a morning warmup is essential, others say it will destroy the engine long-term. Doubtful I'll raise this with my neighbor unless it comes up in conversation, since I prefer to remain on good terms with him, and he tends to be an "old-school" kind of joe.

    Thanks for all the feedback!

Similar Threads

  1. Need help with idle vibrations (Not rough idle).
    By DarienFalks in forum 1988 - 1996 (E34)
    Replies: 6
    Last Post: 07-11-2013, 06:03 PM
  2. rough idle will not pass 1500rpm
    By windsorbimmer in forum 1991 - 1999 (E36)
    Replies: 8
    Last Post: 01-31-2005, 02:30 PM
  3. Rough idling, will not go pass 1500 RPM...HELP!
    By windsorbimmer in forum General BMW Mechanical Help sponsored by RM European Auto Parts
    Replies: 1
    Last Post: 01-29-2005, 07:20 PM
  4. Car Not Holding Idle.....stalling issue...
    By WhiteM32 in forum 1992 - 1999 M3 (E36)
    Replies: 2
    Last Post: 08-09-2004, 04:29 PM
  5. ticking at idle, oil not low
    By orlandoD in forum 1992 - 1999 M3 (E36)
    Replies: 21
    Last Post: 04-01-2004, 06:06 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •