How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask Matt Your Own Question

Matt
Matt, Mechanical Engineer
Category: Mercedes
Satisfied Customers: 21380
Experience:  BEng hons Mech engineering, in auto industry 22 years
12772297
Type Your Mercedes Question Here...
Matt is online now

The fan in the engine spontaneosly comes on making a loud

Resolved Question:

the fan in the engine spontaneosly comes on making a loud noise while driving along the cuts out for a while and starts again.
when the engine is switched off the fan continues for a full minute and sometime longer before stopping. it sometimes the starts again before finally stopping.
the noise is really loud.
Submitted: 9 months ago.
Category: Mercedes
Expert:  Matt replied 9 months ago.

Hello

the engine cooling fan should cut and in out ? this is normal behavior especially if the car is moving slowly

now if the fan is coming on with a cold engine then thats a different matter and I'd 1st consider replacing the engine coolant sensor and also check the state of the wiring between the sensor and the engine loom - check it for chafe damage and hard sections indicating a short

Customer: replied 9 months ago.
the fan does come on at full blast shortly after the car is started, it then shuts off and then as I drive along it comes in again intermittently and the sound is much louder than the sound of the engine usually...for example if I stop at a traffic light.Is it ok to continue driving the car as it is for the time being?
Expert:  Matt replied 9 months ago.

hello

I'd say as long as the engine isn't overheating then yes you're fine to carry on driving the car

Expert:  Matt replied 9 months ago.

Hi

do you still need help?

Bear in mind that the site takes a deposit from you at the beginning and this is held by the site until you rate my answer at which point the cash is split between the site and the expert. I am only paid for my work on this question if you rate my answer, using the star system at the top of the screen. Please do not forget! Thank you

Matt, Mechanical Engineer
Category: Mercedes
Satisfied Customers: 21380
Experience: BEng hons Mech engineering, in auto industry 22 years
Matt and other Mercedes Specialists are ready to help you

What Customers are Saying:

 
 
 
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil
< Previous | Next >
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil
  • Lurch. Thank you very much. I had real doubts about this website but your promptness of response, quick followup and to the point answer with picture was incredible. Charles
  • As a single woman, I really appreciate an excellent and affordable opinion.
    Thank you Geordie, I will not hesitate to contact justanswer in the future!
    Sue
  • Another great insight to what may be the problem. I will have my mechanic take a look at it tomorrow. Thanks again, Frank...you do indeed know your stuff. Jim
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P
  • Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help. Mary C.
  • This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!! Alex
 
 
 

Meet The Experts:

 
 
 
  • Matt

    Matt

    Mechanical Engineer

    Satisfied Customers:

    504
    BEng hons Mech engineering, in auto industry 22 years
< Previous | Next >
  • http://ww2.justanswer.co.uk/uploads/35/350matt/2012-6-7_182356_matsavatr.64x64.jpg Matt's Avatar

    Matt

    Mechanical Engineer

    Satisfied Customers:

    504
    BEng hons Mech engineering, in auto industry 22 years
  • http://ww2.justanswer.co.uk/uploads/EU/eurotec/2012-6-11_13153_mpjaphoto.64x64.JPG Marty's Avatar

    Marty

    ASE Certified Technician

    Satisfied Customers:

    21406
    Bosch Certified Master Technician with over 35 years experience in the automotive industry.
  • http://ww2.justanswer.co.uk/uploads/MI/mikeamechanic/2013-4-2_175558_photo.64x64.JPG mike_a_mechanic's Avatar

    mike_a_mechanic

    Mercedes Mechanic

    Satisfied Customers:

    116
    17 years experience as a auto mechanic, foreign and domestic.5 years running my own repair business.
  • http://ww2.justanswer.co.uk/uploads/MB/MBpaul/2013-8-21_204936_paul.64x64.jpg MB Paul's Avatar

    MB Paul

    Mercedes Technician

    Satisfied Customers:

    212
    Mercedes Benz Qualified Diagnostic Technician
  • http://ww2.justanswer.co.uk/uploads/IN/indytech/2013-8-8_102717_SantoDomingo146598x6402.64x64.jpg Greg's Avatar

    Greg

    Technician

    Satisfied Customers:

    1094
    Automotive diagnostic tech
  • http://ww2.justanswer.co.uk/uploads/TE/techmachine/0601821347169_717372168_8940977_39623330_o.64x64.jpg Ross's Avatar

    Ross

    Diagnostic and repair technician

    Satisfied Customers:

    467
    Licensed diagnostic and repair technician