I have a mk2 focus and it stutters when it accelerates at low speeds.  Sometimes the check engine light comes on as well but not always.  Occasionally there is quite a loud bang sort of coming from somewhere.   

Had the RAC look at it and it also went in for a full service but it is still happening.  It passed its MOT a few weeks ago.   Initially thought it was water getting in to the spark plugs but im not sure.  The coolant level has not dropped.  I know it needs new windscreen washer jets to stop water getting in.  

Wondering if it is not water in the spark plug wells and actually something to do with the fuel.  No idea.  

What codes does it store when the light comes on? Gonna guess p0300 or p0301, p0302 and so on..

I don't see any codes on the front dash panel and I don't know where to look otherwise.  

You’ll need a code reader to find out. 

6 hours ago, Ford2005UK said:

I have a mk2 focus and it stutters when it accelerates at low speeds.  Sometimes the check engine light comes on as well but not always.  Occasionally there is quite a loud bang sort of coming from somewhere.   

Had the RAC look at it and it also went in for a full service but it is still happening.  It passed its MOT a few weeks ago.   Initially thought it was water getting in to the spark plugs but im not sure.  The coolant level has not dropped.  I know it needs new windscreen washer jets to stop water getting in.  

Wondering if it is not water in the spark plug wells and actually something to do with the fuel.  No idea.  

When you change the washer jets; put some silicone sealant around the jets under the bonnet, common problem only affects the 1.6 petrol engine because of its placement under there.

Guide to Fitting New Ford Mist Type Jets on all Models Click Here 

 

Thank you all for these answers.

Do you think that the car will need new plugs and leads?

How much should I expect a mechanic to charge for only removing the water and fitting the washer jets (and applying silicone sealant as recommended by Lenny)?

 

 

Without seeing a car no one can speculate what a car really needs, with that said water in around the ht leads/spark plugs could reduce the ability of the spark plug to ignite fuel because some of all of the energy will be wasted, resulting in similar symptoms to what you describe.

An hours diagnostic would likely reveal the solution and what needs repaired. Without a bit of time into issues you’ll just end up throwing parts at something in hope of a fix. 

regarding the washer jets, silicone grease is my preferred fix for these providing it’s also got the revised washer jets. This is something you could do at home, removing the water in the top of the cylinder head shouldn’t take you long and may also cure the issue you are having for very little cost. 

22 minutes ago, Ford2005UK said:

Thank you all for these answers.

Do you think that the car will need new plugs and leads?

How much should I expect a mechanic to charge for only removing the water and fitting the washer jets (and applying silicone sealant as recommended by Lenny)?

Mechanics time is around 40 per hour plus parts and VAT 

These tasks are quite simple to do yourself saving you around 100 quid minimum, 

Get a Turkey baister from pound land and extract the water from the engine yourself, Also get silicone in Poundland.

Ideally new spark plugs smear a little engine oil around there threads before inserting to prevent them sticking.

And the guide there shows how to change the washer jets, 

Also new ignition leads would probably increase your mpg but the existing ones will keep going well in to the new year,

Its your choice in what you do mate but I always encourage people to do jobs like these themselves.

12 hours ago, Lenny said:

Ideally new spark plugs smear a little engine oil around there threads before inserting to prevent them sticking

Personally I would use copper anti-seize grease.

25 minutes ago, mjt said:

Personally I would use copper anti-seize grease.

Ohh Kinky 😉

Ideally new spark plugs should be fitted 'dry'. NGK are one manufacturer who state there is no need to use an anti seize compound as there is already a factory plating on the threads but also by applying an anti seize compound you will also over tighten them, risking more damage than not applying anything. 

NGK also have an official technical bulletin regarding this, says USA but i'd imagine it applies to all of their products. 

 

That's all well and good if the plugs are only going to get installed and removed once but I wonder what happens if they're removed, e.g. for gap checking, and then refitted. Presumably the "lubricant" plating that will have broken away will then fall into the cylinder as the plug is screwed in again so it won't work a second time. It's well known that the 'water in the plug wells' syndrome can result in the plugs becoming corroded in and then breaking during removal. That happened to my neighbour's Mk 2 whilst in for a service. I'd rather put some anti-seize on and reduce the setting on the torque wrench.

Incidentally I seem to remember that back in the day it used to be recommended to screw the plug in by hand then tighten by a specified angle. This would avoid over-tightening whether or not a lubricant was present and is a much better idea in my opinion.

 I was wondering what washer jet to buy (item from the guide no longer available on ebay and also it was for a mk4 so not sure if that would work) and tbh if anyone had a link to a step by step guide on how to get to the part where the water is (spark plug wells) and suck that water up.  I have tried to find the correct guide and googled it. 

I saw another solution to this problem on youtube about putting a cover on the engine to prevent water getting in.  I'm wondering if there is a missing cover on my engine or something.  I have had 2 garages and the RAC suck water out of the engine twice as well.  The AA flat out refused to suck the water out which I didn't contest but struggled home.  I've recently relocated temporarily to Wales and it rains heavily a lot here.  

 

2 hours ago, mjt said:

That's all well and good if the plugs are only going to get installed and removed once but I wonder what happens if they're removed, e.g. for gap checking, and then refitted. Presumably the "lubricant" plating that will have broken away will then fall into the cylinder as the plug is screwed in again so it won't work a second time. It's well known that the 'water in the plug wells' syndrome can result in the plugs becoming corroded in and then breaking during removal. That happened to my neighbour's Mk 2 whilst in for a service. I'd rather put some anti-seize on and reduce the setting on the torque wrench.

Incidentally I seem to remember that back in the day it used to be recommended to screw the plug in by hand then tighten by a specified angle. This would avoid over-tightening whether or not a lubricant was present and is a much better idea in my opinion.

Fix the water ingress problem then there isn’t an issue. Plugs that are removed routinely generally don’t seize in place so are not an issue.

I've had great success with new washer jets and silicone grease, the few focus’ I look after have never had the wet spark plug wells return. 

these engines didn’t come with a cover as standard, there is one available for it albeit the only one I have seen wasn’t a ford part.

20 hours ago, Ford2005UK said:

 I was wondering what washer jet to buy (item from the guide no longer available on ebay and also it was for a mk4 so not sure if that would work) and tbh if anyone had a link to a step by step guide on how to get to the part where the water is (spark plug wells) and suck that water up.  I have tried to find the correct guide and googled it. 

I saw another solution to this problem on youtube about putting a cover on the engine to prevent water getting in.  I'm wondering if there is a missing cover on my engine or something.  I have had 2 garages and the RAC suck water out of the engine twice as well.  The AA flat out refused to suck the water out which I didn't contest but struggled home.  I've recently relocated temporarily to Wales and it rains heavily a lot here.  

 

The mist type jets were built for the mk3 focus but there physical size is identical to the standard making them a straight swap upgrade, 

Regarding engine cover; there's a part number for a Volvo cover and discussion on this thread: