I’m having issues intermittently with starting my 1.0 ecoboost. 

It sometimes takes up to 3 or 4 attempts to get the car to start. When the key is turned, the engine will turn over once, sometimes twice then nothing almost as if I’m not turning the key properly! Then I’ll try again and it will start as normal. 

Once a month or so, I will have it where I cannot get it to start at all. I’ll put a jump pack on it, and it will start straight away. I connect via the positive terminal and earth post for ease. 

The battery has 12.4v when idle and 14.4v when engine is on. 

It has been happening for about a year now, and in the last year it has had a new battery (Varta Blue), a new starter motor and a new negative/earth cable from negative battery terminal to starter motor, as the garage I took it to said original was corroded at the negative battery end (which they showed me and it was to be fair). The terminals on battery are clean and tight. 

It all points to a bad connection somewhere, but I believe all points have been checked. I fear taking it to a garage will just involve more guess work. 

Any help would be much appreciated! 

Have you replaced the starter relay ?

 

Unofix, I will order one and try it. Thank you. 

I’ve replaced the starter relay but made no difference. It turned over just once first journey. Got engine running on 2nd attempt. 
 

I was just testing the relay when I got home and the engine started the first 2 times but after that I could only get the car to turnover once and couldn’t start the car again. 
 

Measured battery at 12.36v, was about to jump start with jump pack but before I did I gave it another go and it started! Measured battery again with engine running at 15.05v 

 

2 hours ago, Lhalford82 said:

Measured battery at 12.36v, was about to jump start with jump pack but before I did I gave it another go and it started! Measured battery again with engine running at 15.05v 

Your battery voltage of 12.36V when at rest is lowish but not that bad. The fact the the charging voltage with the engine running is 15.05V indicates that the cars smart charge system knows that the battery state of charge (SOC) is lowish and it is trying to recharge the battery quickly.

It's a pity the relay didn't sort the issue but at least an easy thing to try. The next thing would be the ignition switch barrel. You could take it apart and give the electrical contacts a spray with cleaner.