C3: Intermittent Dull Engine Noise and Electric Smell

CitroenWill · Post by **CitroenWill** » 18 Aug 2010, 11:43

Hi All,

I have an unsual intermittent problem with my 2005 Citroen C3 1.4 Petrol.

Sometimes when I turn the ignition, I can hear a very 'dull' noise. It's really hard to describe. I want to say it's like a vibration but I'm really not sure it is. This noise persists until I stop the engine.

When I can hear this noise, the car doesn't seem to idle correctly. Sometimes it fluctuates very slightly and sometimes it can fluctuate wildly.

What concerns me the most is if I drive the car while I can hear this noise, while it seems to drive flawlessly, an electrical burning smell comes from the engine. It smells similar to burning plastic.

The frustrating thing is it doesn't happen every time. Sometimes I can go days with a flawless car (well, as flawless as Citroens can be) and sometimes it happens very regularly. It doesn't appear to have any relation to outside temperature.

I have the car booked into the Citroen garage on Wednesday and I am seriously concerned about the £95 per hour charge I have been quoted because there is a very good chance that they will not be able to reproduce the problem.

Does anyone have any ideas at all of what could be causing this problem?

Many thanks in advance,

Will

Post by **RichardW** » 18 Aug 2010, 12:03

Will,

Does it happen when you turn the ignition on, or when you start the engine? My money would be on the fuel pump (if it comes on at ignition); or the power steering motor (assuming it's electric

) if it happens at engine start. Could also be a problem with the alternator I guess. Hopefully they won't spend too long looking at it if they can't easily figure it out, spending your £95/hr....

CitroenWill · Post by **CitroenWill** » 18 Aug 2010, 12:08

RichardW wrote:Will,

Does it happen when you turn the ignition on, or when you start the engine? My money would be on the fuel pump (if it comes on at ignition); or the power steering motor (assuming it's electric ) if it happens at engine start. Could also be a problem with the alternator I guess. Hopefully they won't spend too long looking at it if they can't easily figure it out, spending your £95/hr....

Hi RichardW,

Many thanks for the prompt response.

It happens when I turn the engine on. Does this change what you think at all?

Edit: I just read you post properly. It's interesting that you say power steering because I have had a few intermitten issues with the steering also. Could this explain the idle problem, though?

-Will

CitroenWill · Post by **CitroenWill** » 18 Aug 2010, 13:53

I just turned the car on with the bonnet open (First time I've done this, I know NOTHING about cars).

There is some smoke coming from the front left of the engine, where the timing belt is located. It's this smoke that is giving off the electric burning smell.

Does this shed any more light on the issue?

Post by **RichardW** » 18 Aug 2010, 14:04

OK Will, diagnosis is developing....

If it's coming from that area of the engine, then it is most likely the alternator (although.... does the car have air con, and is evidence of the fault in anyway related to whether the A/C is switched on - noting that it may be switched on by simply putting the direction slider to demist?). Now, as to whether it's really the alternator at fault, or something else (like the steering pump!) that is overloading the alternator will need a bit more investigation. I'd be tempted to take it somewhere else other than a Citroen garage as:

a) this is not really a Citroen specific fault, so any garage should be able to sort it
b) they won't charge £95 / hr
c) they won't charge you £200+ for a new alternator if that does turn out to be the fault.

CitroenWill · Post by **CitroenWill** » 18 Aug 2010, 14:33

RichardW wrote:OK Will, diagnosis is developing....

If it's coming from that area of the engine, then it is most likely the alternator (although.... does the car have air con, and is evidence of the fault in anyway related to whether the A/C is switched on - noting that it may be switched on by simply putting the direction slider to demist?). Now, as to whether it's really the alternator at fault, or something else (like the steering pump!) that is overloading the alternator will need a bit more investigation. I'd be tempted to take it somewhere else other than a Citroen garage as:

a) this is not really a Citroen specific fault, so any garage should be able to sort it
b) they won't charge £95 / hr
c) they won't charge you £200+ for a new alternator if that does turn out to be the fault.

Hi RichardW,

Interesting.

My A/C hasn't worked for many months and I have also had an issue (which I believed to be relatively minor) where even when the switch is set to 0 there is a small amount of air coming out of the vents, i.e. I always had to have either cold or hot air coming out.

I wonder if this could be related to the alternator being "overloaded"? Everything is turned off according to the switches though.

The good news is it no longer seems to be intermittent. Every time I turn the engine on it makes the dull noise and gives off the smoke/smell.

Post by **myglaren** » 18 Aug 2010, 20:09

From the information supplied you may be better served by an auto-electrician.

Try and get personal recommendations as some are as bad as the dealers for charging high prices and misdiagnosing/failing to satisfactorily repair the defect.

CitroenWill · Post by **CitroenWill** » 25 Aug 2010, 11:17

Just had the diagnosis from Citroen.

They said the spark plugs are knackered and the ignition coil is bust. they are also doing a software download.

Does this sound right? I was so sure the diagnosis was going to be a problem with the alternator.