1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Coolant warning alarm

Discussion in 'A3/S3 Forum (8L Chassis)' started by gash, Apr 29, 2012.

  1. gash
    Offline

    gash Member

    Joined:
    Apr 9, 2012
    Messages:
    31
    Likes Received:
    0
    I started a thread a couple of days ago saying I had a oil pressure warning come on. Turns out that it was actually a coolant warning.

    To be honest it is a bit if a relief because I was worried I may have done some damage to the engine if it was ran dry.

    Brings me to the next question of why the alarm came on, it was only on for about 20 secs then went off again, not seen it since. Any one got any ideas why this warning came on for such a short period of time?

    Temp gauge is bang on 90.

    I was sitting on a slight hill at the time, could this have caused it?
    #1
  2. <tuffty/>
    Offline

    <tuffty/> Badger 5 Edition Staff Member Moderator

    Joined:
    Sep 14, 2008
    Messages:
    15,721
    Likes Received:
    20
    Check the level of coolant in the expansion bottle...

    <tuffty/>
    #2
  3. gash
    Offline

    gash Member

    Joined:
    Apr 9, 2012
    Messages:
    31
    Likes Received:
    0
    Cheers tuffy al have a look tomorrow.

    Any idea why it would come on for a short period then back off again?
    #3
  4. <tuffty/>
    Offline

    <tuffty/> Badger 5 Edition Staff Member Moderator

    Joined:
    Sep 14, 2008
    Messages:
    15,721
    Likes Received:
    20
    Generally they beep to grab your attention then stay on the dash for a bit... could be that getting onto a flat bit of road was enough to wet the sensor electrodes enough to clear it...

    Gauge being bang on 90 means little tbh... the gauge hits 90 then stays there until something like 100/105 degrees (can't remember the exact number) then throws a warning on the dash and then I think the gauge increase in temp..

    I suspect you r issue is more likely low coolant though...

    <tuffty/>
    #4
  5. gash
    Offline

    gash Member

    Joined:
    Apr 9, 2012
    Messages:
    31
    Likes Received:
    0
    Cheers again tuffy, as I said I will check tomorrow and post tge out come.
    #5
  6. Gops
    Offline

    Gops 6th gear @7000rpm

    Joined:
    Nov 6, 2009
    Messages:
    2,640
    Likes Received:
    7
    Wasnt there an issue with the coolant bottle level sensor? I had it pop up but coolant level was fine. Put about 100ml in and it went! Comes up on cold days usually.
    #6
  7. vfr800
    Offline

    vfr800 Member

    Joined:
    Feb 28, 2012
    Messages:
    741
    Likes Received:
    0
    If the coolant level is fine it will be the coolant level sender. (in my experience - it's worse when it's cold)

    Open the cap on the coolant expansion tank, when you look inside there are two metal probes.

    Over time these built up crud/limescale which prevents the sensors from sensing the correct level.

    There are two ways to fix.
    1) Buy a new expansion tank. £15? ish.
    2) Carefully clean the probes.

    I opted for option 2 on my A3 because if I screwed it up a new tank wasn't much and I was about to sell the car anyway.

    I removed the header tank and rinsed it out, I used a long flat-bladed screw driver to carefully scraped down the length of the wires. You can feel when you're removing limescale or down to bare metal. Do your best to clean them off all around. Rinse it out again and refit.

    Liam
    #7

Share This Page