Loss of acceleration

[Outkastmike]

Hi.

I have been having power loss issues with my 2012 1.2 fiesta style with 11k on the clock..

The problem happens at the usual place on the road roughly about half a mile along the road from where I live and I'm usually accelerating in 5th gear to about 50mph when I loose acceleratoration from anything from a split second to a few seconds and then it suddenly comes back, it's as if I have just  removed my foot from the pedal momentarily,but obviously my foot is still depressing the pedal and there's nothing there until it judders slightly back to life either by fethering the pedal or changing down a gear.(whether that helps it is debatable).

I have had it in too a Ford dealer and also a independent dealer who are both telling me they don't know the problem or how to fix it,ive had them plug it into the computer but no faults are showing and fuel pressure is also fine.

I asked about a possible fuel filter blockage but was told due to it's low mileage that its unlikely the problem.

 

 

 

[jbell]

Try using third or fourth until you've reached cruising speed. The 1.2 won't be powerful enough to reliably accelerate (especially if on a hill) at 50 in 5th. 

[Outkastmike]

It did it again this morning after picking it up from the Ford dealer but I was in 3rd gear,total loss of acceleration for a couple of seconds then it comes back.

It's not changing gear too early that's the issue it's almost like fuel starvation as there's nothing at the pedal but I have been told by two different garages that its probably not the fuel filter due to its low mileage.

[TomsFocus]

You could've filled up with some contaminated fuel at 50 miles let alone 11,000 so I'd say it's worth trying a filter change personally.

Could also be an ignition fault, dodgy coil pack maybe.  Does it get any worse when warm?

[stef123]

This certainly doesn’t add up to being a fuel filter or petrol contamination issue. Also I don’t think your year of car has a filter as such. 

 Live data recording during a drive where you can recreate the fault is probably your best hope. 

 

[Outkastmike]

24 minutes ago, TomsFocus said:

You could've filled up with some contaminated fuel at 50 miles let alone 11,000 so I'd say it's worth trying a filter change personally.

Could also be an ignition fault, dodgy coil pack maybe.  Does it get any worse when warm?

Only does it from a cold start in the morning usually within half a mile,once it's done it the car runs just fine for the rest of the journey.

[Outkastmike]

26 minutes ago, stef123 said:

This certainly doesn’t add up to being a fuel filter or petrol contamination issue. Also I don’t think your year of car has a filter as such. 

 Live data recording during a drive where you can recreate the fault is probably your best hope. 

 

Ford garage tried the live data recording but typically he said it didn't miss a beat when he test drove it so rang me and said there was nothing he could do,so went and picked it up and hey presto it did it within half a mile on the level.

[stef123]

It’s a hard one to call if the person looking at it cannot replicate the fault but you don’t have much else to go on. Perhaps if you could get someone to connect the car to a scan tool and you drive it, certainly if you seem to be able to get the fault to occur.

[Outkastmike]

I have a Torque pro OBD code reader so I'll download the app and plug it in and see what occurs.

First garage I went to test drive it and the fault occurred with him when he drove it but nothing showed up on his laptop and he advised taking it to a Ford dealer as he said he was baffled by it and didn't want to spend several hours fault finding at great cost to me.

[Russ]

Had a mate who had similar on a Vauxhall (bad word). It was only when they looked at live data they figured it was the plugs starting to break down.

I also had a slight misfire/loss of power on hard acceleration on my last mk6 fiesta which lasted 2 years until I tested the plug leads and found one was a ‘duffer’. (Just an idea check the easy/simple stuff first)

[stef123]

Live data can be great, for example some scan tools you can see misfire data - very useful. 

[Outkastmike]

Didn't get a chance to test the car with the code reader due to the hard frost this morning but did let the car tick over for ten minutes to defrost it and didn't have any issues on the way to work so it's obviously connected to setting off from cold in the mornings.

[stef123]

Perhaps something from it changing from open loop to closed loop control. 

Impossible to say without any data sadly. 

[tam51n]

Hi Outkastmike,

I know this post is a couple of years old, but did you ever find the cause for the loss of power? A similar thing is happening to my fiesta.

Thanks

[Dean92]

Was this issue ever resolved?

I am experiencing the exact same issue with my 2012 1.6 fiesta. It happens from a cold start usually within the first few minutes of driving. Sometimes it only lasts a few seconds, other times I've had to come to a complete stop before it will spring back to life.

[spadder4]

On 1/19/2019 at 8:22 AM, jbell said:

Try using third or fourth until you've reached cruising speed. The 1.2 won't be powerful enough to reliably accelerate (especially if on a hill) at 50 in 5th. 

Exactly the same issue with my 2017 1.2l.

Changed spark plugs, checked ht cables etc.  Acceleration fades appox 1 mile from a cold start every day.

Did you get to the bottom of it?

[philb95]

Did you ever get to the bottom of this? 
im experiencing the exact same fault on a 2011 fiesta titanium 

[philb95]

I had this exact fault. Turned out to be a faulty crank shaft sensor. 
Quite a cheap and easy fix! 
 

All you need is the sensor, a low profile 8mm socket wrench and appropriate gear to jack your car up safely. Plenty of useful videos on YouTube. 
 

Hope this helps.

[Bobr]

Around 2006/7 there were a lot of problems with faulty coil packs. I had to have a complete change on a brand new 2006 Fiesta Ghia.

[elliechxffe]

Hi, I am experiencing all the same issues as above, ie drives fine suddenly loss of power and then spring back into life after a few seconds! Sounds minor however becoming very annoying haha! 
just wondering if anyone had it fixed and worked a way around it? 
 

thanks 

[unofix]

🤔🤔

[Jim Fiesta]

I know this is an old topic but i had this problem for nearly four months and it drove me nuts. After many mechanics looking at it, it turned out to be the "Engine Coolant Temperature Sensor". If people are losing power or having this problem only when the car is cold then i highly recommend trying this. I had to finally bring it to an old school mechanic as mechanics these days only plug in their diagnostics tool and if no faults shows up like mine they just kick you out the door and don't want to fault find. I also changed, leads, sparkplugs, coil pack, throttle body and accelerator assembly before bringing it to a proper old school mechanic who finally fixed in within 3 hours. Hope this works for anyone having the same issue.