Page 2 of 2 FirstFirst 12
Results 11 to 19 of 19

Thread: Oil light keeps coming on and off randomly...

  1. #11
    Join Date
    Nov 2007
    Location
    BANCHORY
    Posts
    3,408
    Quote Originally Posted by gurlsm@rter View Post
    The place I bought it from checked the oil level, coolant level, pressure tested it, and reported back that everything looks ok and there are no leaks or concerns.
    The easy way to diagnose your flickering oil warning light is to connect a pressure gauge and read oil pressure.

    Normal oil pressure on any engine at operating temperature is typically above 3 bar. Oil pressure switch on a Smart 451 with 1.0 litre engine will illuminate oil pressure warning lamp when pressure drops down to 0.2 bar and lower.

    If your garage is competent and worth their salt, they should aleady have checked oil pressure.

    Request you money back if they cannot sort this out.

    One thing is for sure, although responsible for most of our sufferings these dark days, Brexit and Boris cannot be blaimed for this.
    Drives a Smart Cdi - 65 to 85 MPG

  2. #12
    Join Date
    Nov 2004
    Location
    North Weald, Essex
    Posts
    181
    When did it have an oil change? Maybe a clogged oil filter might cause this. Simple & fairly cheap job to do. Just a thought.

  3. #13
    Join Date
    Nov 2007
    Location
    BANCHORY
    Posts
    3,408
    Read about oil pressure on Wikipedia.
    Scroll down a wee bit and study the four reasons for low oil pressure.
    https://en.wikipedia.org/wiki/Oil_pu...ustion_engine)
    Drives a Smart Cdi - 65 to 85 MPG

  4. #14
    Join Date
    Apr 2009
    Location
    Ecosse
    Posts
    3,803
    Quote Originally Posted by Mr T View Post
    When did it have an oil change? Maybe a clogged oil filter might cause this. Simple & fairly cheap job to do. Just a thought.
    Usually there's a by-pass valve for that eventuality.

    That it only occurs 8 minutes in might imply bearings - or an electrical short.
    If this was my car I think I'd wire in a temporary auxiliary light with new wiring all the way back to the oil pressure switch and disconnect the existing wire from the switch for now. If it illuminates as before then it points to internal problem. If it stays off - electrical short on the car's own wire. Just to eliminate any external possibility before cracking open the wallet.

    NB. post edited as previous suggestion wouldn't work.
    Last edited by pinger; 06-02-2021 at 03:16 PM.

  5. #15
    Join Date
    Oct 2010
    Location
    Belfast, NI
    Posts
    1
    Quote Originally Posted by tolsen View Post
    The easy way to diagnose your flickering oil warning light is to connect a pressure gauge and read oil pressure.

    Normal oil pressure on any engine at operating temperature is typically above 3 bar. Oil pressure switch on a Smart 451 with 1.0 litre engine will illuminate oil pressure warning lamp when pressure drops down to 0.2 bar and lower.

    If your garage is competent and worth their salt, they should aleady have checked oil pressure.

    Request you money back if they cannot sort this out.

    One thing is for sure, although responsible for most of our sufferings these dark days, Brexit and Boris cannot be blaimed for this.
    Thanks for that info. Much appreciated. They advised me that the oil and coolant levels were checked and fine, plus pressure checked. The guy I'm dealing with seems like a pretty sound person and is willing to help fix the issue, so hopefully its nothing too crazy.

    Quote Originally Posted by tolsen View Post
    One thing is for sure, although responsible for most of our sufferings these dark days, Brexit and Boris cannot be blaimed for this.

  6. #16
    Join Date
    Oct 2010
    Location
    Belfast, NI
    Posts
    1
    Quote Originally Posted by pinger View Post
    Usually there's a by-pass valve for that eventuality.

    That it only occurs 8 minutes in might imply bearings - or an electrical short.
    If this was my car I think I'd wire in a temporary auxiliary light with new wiring all the way back to the oil pressure switch and disconnect the existing wire from the switch for now. If it illuminates as before then it points to internal problem. If it stays off - electrical short on the car's own wire. Just to eliminate any external possibility before cracking open the wallet.

    NB. post edited as previous suggestion wouldn't work.
    Thanks for the info. I would love to be able to do things like this but I just don't have the knowledge about cars, let alone Smarts - I don't think I could be trusted to put things back together right Any suggestion though is gratefully accepted as I could pass it onto the guy at the place I got the Smart from who is looking at the issue if all else fails. Ta.

  7. #17
    Join Date
    Oct 2010
    Location
    Belfast, NI
    Posts
    1
    Quote Originally Posted by Mr T View Post
    When did it have an oil change? Maybe a clogged oil filter might cause this. Simple & fairly cheap job to do. Just a thought.
    I'll double check that as that sounds like it could be an option. Thank you.

  8. #18
    Join Date
    Oct 2010
    Location
    Belfast, NI
    Posts
    1
    Quote Originally Posted by tolsen View Post
    Read about oil pressure on Wikipedia.
    Scroll down a wee bit and study the four reasons for low oil pressure.
    https://en.wikipedia.org/wiki/Oil_pu...ustion_engine)
    Brilliant! That's a great explanation on the possible issues. Thank you.

  9. #19
    Join Date
    Apr 2009
    Location
    Ecosse
    Posts
    3,803
    Wiring another light to eliminate the possibility of a chafed wire shorting is the easiest and cheapest of all the options. Start with the simple and cheap.
    If such a light still lights up then it's not the wiring and the problem is within the engine. You really don't want to spend a fortune on stripping the engine to find later that a chafed wire was the cause.
    Any mechanic can knock up a test lamp in 15 minutes. One lead from the bulb to a positive (go straight to battery or cig lighter) and the other to the terminal on the oil pressure switch.

    If the problem is with the engine then it's less likely to be blockage - more likely leakage. The fact that it only occurs some time after start up (when the oil has heated and thinned a bit) suggests this.

    When it happens, are there any noises? Mechanical knocking type noises?

Posting Permissions

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