Ford Focus - Rattling noise

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Fri 28 Aug 2015 09:08
Ford Focus - Rattling noise - pricklybuzz

I’m hoping someone can give me some help, I have a 2003 Focus 1.6.

I’ve had this car about 10 months, I was given it by a family member and I wanted to bring it back up to a nice condition so I would have a decent car for the next 2-3 years as I’m saving for my first house!

Basically it has an intermittent engine rattle which sounds to me like pinking, this happens just as you apply light throttle for around 2-4 seconds. I have spent so much time and money trying to rectify this but I have now run out of ideas and things to replace.

So far I have changed:

  • Engine (the old one was using a lot of oil so I replaced it for a well maintained low mileage unit)

  • CAT (had the original fitted so thought I would replace this)

  • Up-stream (pre-cat) lambda sensor

  • Spark plugs, leads and Coil pack (all genuine Ford)

  • MAP sensor

  • CHT sensor

  • Knock sensor

  • Fuel vaporizer

  • ECU

  • Fuel Filter

  • Fuel pressure regulator

  • PCV valve and breather pipes

I have tried running the car on higher octane fuel and it made no difference.

I have checked all pipes for damage or collapsing.

It only ever does this when warm and the hotter the weather the worse it is (it hardly does it at all in the rain)

The only things I am now left with is low fuel pressure although this doesn’t explain why it only does it when hot and the downstream (post-cat) lambda but I didn’t think this affected fuelling, I thought it was purely there to monitor the cats efficiency?

Please help!

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Fri 28 Aug 2015 09:57
Ford Focus - Rattling noise - RobJP

The car is worth a few hundred pounds - at most. Going by the list of parts and time/labour you've thrown at it, you're just burning money by changing anything else. I dread to think of how much you've spent on it - going by the list, must be well over a thousand pounds.

It's an old car. They develop rattles, quirks. A lot of them are just there, nothing you can do about it. It's a factor of 12 years of wear.

As far as I see it, you do one of three things with a car of that age.

1. Take it to a garage and get it diagnosed properly

2. Replace parts at random (like you've done).

3. Ignore the rattle, turn up the stereo, and keep running it until it dies.

So far, you've done (2). Repeatedly. And it's gotten nowhere each time.

Remember, there's a definition for people who keep on doing the same thing, and expect different results.

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Fri 28 Aug 2015 10:01
Ford Focus - Rattling noise - elekie&a/c doctor

As above.Looks like you got a top score of 180 at parts darts.None of which would cause a rattle in the engine.Perhaps you need to use a better guess-o-meter.?

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Fri 28 Aug 2015 10:15
Ford Focus - Rattling noise - pricklybuzz

I never said i was guessing, all of the parts i have replaced could cause a rattle, if the engine is pinking for example due to a lean mixture?

I have not spent anywhere near £1000 as i work in the trade and have had some help, however i thought i would ask on here for a wider audience of ideas as myself and the people helping me are stumped.

The car has a cirtain centemtal value although this may not count for alot of people as i understand it is 'just a bit of tin'!

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Fri 28 Aug 2015 10:38
Ford Focus - Rattling noise - RobJP

As you say, all of the parts you've replace could cause a rattle. So could a loose engine mount, a loose gearbox mount, a loose suspension mounting that impinges on another point, a loose exhaust mount, a loose steering rack component, a worn bush somewhere ... the list is endless.

And if you've replaced all of those parts on your list, and the rattle is still there, then you know what : In spite of all your protests, you were guessing, and guessed wrong. Repeatedly !

You 'work in the trade'. Please don't put up where you work, as if the policy there is to replace random parts in the vain hope that, eventually, you'll fix a fault, then if you name it on here I'd imagine your workload will plummet.

You've also made the first, biggest mistake of car ownership. Again, a funny thing for someone 'in the trade' to do : you've gotten emotionally attached to a car. At the end of the day, it IS just a piece of metal. Treat it any differently, and you are asking for trouble.

The car is 12 years old. It has a rattle. That does not mean it has a fault.

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Fri 28 Aug 2015 10:44
Ford Focus - Rattling noise - hardway

About the only thing you haven't changed,

and it would have been my first suspect given the temperature factor is the coolant temperature sensor.

Chuck cash at that,

'coure there's also the inlet air temperaure to consider.

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Fri 28 Aug 2015 11:19
Ford Focus - Rattling noise - pricklybuzz

Well that very un-helpful thanks!

I thought i would come here for a bit of friendly advise of ideas of how to rectify a fault....i was wrong.

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Fri 28 Aug 2015 11:26
Ford Focus - Rattling noise - RobJP

You came on here asking (as per the very first line of your post) for help.

The very best advice I can give you is to stop burning money for the hell of it, because that is all you are doing, and all you have been doing.

Just because that isn't what you wanted to hear, doesn't mean it isn't helpful.

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Fri 28 Aug 2015 19:57
Ford Focus - Rattling noise - Andrew-T

I thought i would come here for a bit of friendly advise of ideas of how to rectify a fault....i was wrong.

Yes, the replies were a bit blunt perhaps. But as you are 'in the trade', can't you or your colleagues decide what may be rattling against what? ('a rattle' is not a very specific description).

I'm not in the trade. But old-school mechanics used to be able to make a good stab at what a rattling engine needs.

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