Hi all,

Firstly, apologies for not fully utilizing the search function, I will have a good look over the forums tomorrow, just wondered if someone could get my an answer quickly.

Just bought a MK7.5 Zetec S 1L Ecoboost, had the belts done 3k miles ago, engine sounds lovely so no worries about belt etc. I must have made it about half a mile before the engine just cut out and would not restart, no crank and asking for clutch and brake to be pressed, then service engine now appears.

By pure luck a mechanic walked passed, did the relink process for the key and eventually the car cranked but would not start. I cleared the codes for FORScan and was able to move the car to a friends house nearby. When I pulled up it started again no problems.

 

I was told it may have a Lambda Sensor fault, which does appear in the data but wonder if there are further issues. I have attached the FORScan details below

 

Thank you all in advance for any assitance, and again, apologies for not using search first. I promise I will have a good look tomorrow!

Fiesta.txt

Hi,

The clutch switch is the reason it asked for both brake ands clutch to be pressed to start.  However, it's showing faults for all of the pedals.

I'd say the lambda sensor is the least of your worries from that list.  Hopefully just a dodgy battery or an alternator charging fault.  Otherwise it's looking like wiring loom damage.

That's what I've been reading. Someone pointed to the same two accelerator faults was due to a broken wire on a connector under the battery. Going to do a little live fault finding tonight, see if I can find anything obvious. Will be checking the battery voltage too, and can do a drop test at the weekend. Charge voltage looks good, 13.3v one one of the tests mentioned in the above fault log

1 hour ago, Hobbs92 said:

Charge voltage looks good, 13.3v one one of the tests mentioned in the above fault log

13.3 volts is way too low for engine running.  Needs to be over 14v to charge effectively.  13.9v is the failsafe for when the SmartCharge system is broken.

Alternator is not charging the battery correctly.

Disconnect the smart charge plug on the alternator and re-check the battery voltage with the engine running at a fast idle. It should be 13.95V which is the default charging voltage in the event that the smart charge fails.

If you find that the voltage is less than 13.95V with the smart charge connector disconnected then the alternator is at fault. If the voltage is correct with the plug removed then there is a break or damage to the smart charge sense wire. The usual problem is the wire corrodes just at the point it enters the plug.

With the system fully working and no faults, the charging voltage will be around 14.4V and as high as 14.9V

Will keep an eye on the alternator, only just got the car running properly.

Seems both Lambda sensors were at fault,and someone had already been at the post cat one.

Done about 25 miles in it since swapping the sensors and so far no issues, no codes, runs really nice too. Going to keep monitoring it and understand what it's doing