Ford Focus rough idle

The J Stands for Jay

I have a 2007 1.6 Ford Focus petrol. I hadn't noticed, but the wife had said it was occasionally idling a little rough at traffic lights etc. As she hasn't been driving too long she put it down to something she was doing wrong.

The car was serviced two weeks ago and since then it's a lot more noticeable. Could something done during the service have had an effect and how can I sort it out?

Anjobe

May be something to do with spark plugs changed during the service, but in all honesty there are a lot of possible reasons why the engine may not run smoothly at idle so you would need to get this checked out by a mechanic.

I had a very lucky escape with the timing belt on my wife's car in the winter after I noticed it idling roughly one morning as I scraped the frost off the windows!

Hal1

Bring it back to where you got the service. They may have overlooked something.

mphalo1

9/10 times it's a sensor causing that! get them to plug diagnostics in to check for you after you explain ,It shouldn't be a problem if you are a valued customer

mphalo1

plus you say since the service it's a lot more noticeable which tells me it was already kinda happening in the car before it got serviced so i wouldnt say its anything to do with them

punisher5112

My guesswould be coil pack.

These constantly go and easy got and fixed you can get in a motor factors and come with pack,leads and spark plugs as all these need to be replaced.

mphalo1

i do know sometimes when filling an engine with oil (carelessly ) oil can find its way down the sparkplug holes drenching the nearest coil in oil causing similar problems too! but failure of the coilpack would cause it to run on 3 cylinders or less r
Making the car run really bad , I'd say its the maf sensor or crank sensor acting up as its only not idling as well as it should

Bigus

Focus don't like anything other than FORD spark plugs, they're cheap from a Ford main dealer but mechanic probably got what is normally a reputable brand from his motor factors, that is of course if plugs were changed, otherwise coil pack problem.

The J Stands for Jay

mphalo1 wrote: »

9/10 times it's a sensor causing that! get them to plug diagnostics in to check for you after you explain ,It shouldn't be a problem if you are a valued customer

Torque on my phone isn't showing any errors.

mphalo1

Is it hunting up and down at idle from 800- 1000 rpm or just barely skipping beat at idle?

Kopparberg Strawberry and Lime

McGaggs wrote: »

Torque on my phone isn't showing any errors.

Torque won't show as much as an actual diagnostics.

I hear delphi diagnostics are good on ford's

The J Stands for Jay

mphalo1 wrote: »

Is it hunting up and down at idle from 800- 1000 rpm or just barely skipping beat at idle?

Idling at about 750, and there'll just be a vibration you can feel but doesn't move the needle. Very occasionally it will drop a little, maybe to 700, but it's pretty rare.

truedoom

some drain on the electrical circuit maybe? wrong viscosity of oil? bad petrol? could really be anything. Any smoke coming out the back?

The J Stands for Jay

truedoom wrote: »

some drain on the electrical circuit maybe? wrong viscosity of oil? bad petrol? could really be anything. Any smoke coming out the back?

No smoke. No idea about the rest.

munchkin_utd

funny, I've a 2007 1.8 petrol focus and it too can also be strangely rough at times when idling, but worst when starting from cold in the mornings. My problem too is that my reference is mazdas and toyotas which seem in general to be a smoother engine anyhow - so I'm a little critical of the focus I'd have to admit, maybe i'm expecting too much.

Thing is though that its much smoother when it gets a chance to warm up, so possibly this is a factor with your wife if she is only doing short runs to shops/ school and the engine hasnt had a chance to warm up??

mphalo1

sounds like its idling to low , all you can do is check all the pipes are good and have no leaks whatsoever especially all the small black ones ( vacuum pipes) buy carb cleaner and clean your idle air control valve and throttle body ,, if that doesn't fix it you may have a mechanic look at it ,, it should be idling at 800 really after its warmed up

The J Stands for Jay

munchkin_utd wrote: »

Thing is though that its much smoother when it gets a chance to warm up, so possibly this is a factor with your wife if she is only doing short runs to shops/ school and the engine hasnt had a chance to warm up??

Maybe that was the case previously, but since the service, it happens even where warmed up. Weekend before last I drove to Cork and it was doing it In the queue at the roundabout at the end of the M8 having come all the way from Dublin.

mphalo1

sounds like its idling low try cleaning the IAC valve with carb cleaner and check for any vacuum leaks ,you really should have a mechanic look at it if that doesn't fix it as it could be so many different things could even be the tps (throttle position sensor ) try cleaning the idle air control valve first ..

mphalo1

@ munchkin_utd if your temp gauge is really slow to go up in the mornings then its your thermostat stuck open causing rough idle until it warms up, hope all this helps you

The J Stands for Jay

And now my wife has called to say the car won't start. From the way it's behaving, it sounds like a flat battery.

SoapMcTavish

mphalo1 wrote: »

sounds like its idling to low , all you can do is check all the pipes are good and have no leaks whatsoever especially all the small black ones ( vacuum pipes) buy carb cleaner and clean your idle air control valve and throttle body ,, if that doesn't fix it you may have a mechanic look at it ,, it should be idling at 800 really after its warmed up

++ to this - Idle issues I've had have always needed throttle body cleaned - lots of carb cleaner ....

The J Stands for Jay

Garage diagnosed a faulty battery. New battery installed, problem remains.

mphalo1

go to a different garage

The J Stands for Jay

Brought it back today. They said it was a spark plug issue. Seems to have fixed it

Bigus

Bigus wrote: »

Focus don't like anything other than FORD spark plugs, they're cheap from a Ford main dealer but mechanic probably got what is normally a reputable brand from his motor factors, that is of course if plugs were changed, otherwise coil pack problem.

McGaggs wrote: »

Brought it back today. They said it was a spark plug issue. Seems to have fixed it

Ahem

punisher5112

McGaggs wrote: »

Brought it back today. They said it was a spark plug issue. Seems to have fixed it

exactly