Hi

I recently just bought my fiesta 1.4 tdci 06’

Everything was going good the first couple of days until I got a full tank of fuel

For 15 minutes it was running good, when It suddenly loses Rpm and gets it back in a second (my foot is all the time on gas pedal)

After some time it happened again, and started to happen more and more often while sometimes it shows different lights on and off on the dashboard, Engine Check, Oil Check, Battery Check

After around 50 miles of doing this it shut down on the highway

It turned on right away

Got it checked and they said alternator or battery, checked the battery, it was running fine and charging correctly

When the car is turned on and not moving, it doesn’t shut down, only when driving starts to lose rpm and turns off

Could it be bad fuel or is the computer showing bad faults and indeed it might be the battery or some injector ?

I try to keep fault diagnosis simple and go for the obvious

In your case car going OK - re-fuel and car not OK is a bit of a clue

Was the tank nearly empty when you re-fuelled?

If so when you filled it you could have dislodged dirt and sediment from the bottom of the tank into the system which can clog up amongst other things the fuel filter - when was it last replaced? Dirty fuel in the filter will block the free flow of juice and cause engine misfire and even stoppage which in turn throws up fault codes (often unrelated to the real cause). After a while when engine is off the fuel gunge settles until the car is started again and the dirt is sucked back into the system and off it goes again.

I would suggest a new fuel filter as a cheap and likely fix for the problem.

It may of course be other things but start with the obvious first 👍

Thanks for the reply

Yes the fuel tank was nearly empty when I re-fueled

Filters were last changed 6-7000 miles earlier, it can be that one.

However now I am worried if it has caused other problems to the car

If it is about dirt my question is why would lights go on and off on the dashboard ?

you really need your own fault code reader to see what fault codes are logged. But I will warn you that the car can hold fault codes for a long time and they don't records dates they arise. So you really need to note down the fault codes, clear them, drive it a bit and see what codes reappear.

A good fault code reader (for use with laptop or mobile phone) is less then 20 GBP.  Garages often charge more than that to read the fault codes for you.(I don't know what country you are in)

I tried that in two different computers not with the exact fault code reader but same type of car I think

I am in Albania and actually here is very cheap around 5 EUR xD

One reader told is alternator and clutch, after restart it showed nothing

The other reader showed Battery, but after checking it showed good charging around 14.1 14.2