Hi all

I have a Mondeo mk5 2015 1.6TDCi with 40k miles on it. It's developed a squeaking/rubbing/chirping sound when cold that completely disappears when the engine is hot. Also when driving it cold the noise goes when accelerating and comes back when I take my foot off.

I've noticed that the aux belt tensioner moves when cold but when the engine is hot it's totally still.

The noise doesn't come back until the engine is stone cold, normally the next morning. It doesn't sound like a rumble or rattle, more like a rubbing/squeaking/chirping. There are no other symptoms (at the moment!)

Could this just be a bad aux belt or tensioner? I would be very grateful for any feedback or advice. Thanks!

On this engine it is very easy to slip the belt off and run the engine without it briefly to confirm that the noise is something to do with the aux belt setup.

For the sake of a tenner, you might as well replace the belt first.  If the problem is still there, you can then replace the tensioner.

Great thanks, I'll ask the garage to do that when it goes in. 

Would you know if the tensioner should be moving when the engine is cold? Thanks

10 minutes ago, MartinTM said:

Great thanks, I'll ask the garage to do that when it goes in. 

Would you know if the tensioner should be moving when the engine is cold? Thanks

I can't remember in all honesty.  I had to change mine because the spring seized in one position and the bearing sounded like a roller skate.  When I fitted the new one, there was a lot of movement on it to start with.  But I never consciously checked it again.

Hi all, conclusion to this in case it helps anyone in the future - it was the water pump! Had the timing belt kit done and solved it.