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D2 - Engine Bay Everything under the bonnet

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Old 20th November 2018, 02:58 PM
HPsauce HPsauce is offline
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Default Gentle tapping noise from idling cold engine.

I've noticed this before, so it's not new, but I started the car today after a couple of weeks non-use and got out to clear debris from a wiper and could hear it.
Cold, wet, miserable day so I didn't open the bonnet to investigate/locate.

Regular very light tap, not harsh more of a quiet duh, duh, duh noise roughly 3 to 4 times a second with the engine doing a fast cold idle. Could have been a belt or bearing or anything rotating I guess.

At that frequency, any thoughts what it might be and whether to worry?
Can't hear it in the car with the doors shut and IIRC it's not there when warmed up.
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e.g. Cruise control, NavPlus/TV, Bose, GSM, Xenons, Solar roof, Parking sensors, Alcantara/leather everywhere of course. (internal dimming mirror added later)
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And before that a lot of Rover 800s, a few oddities, a lovely Triumph Dolomite 1850HL with Overdrive and way back in my schooldays an Austin Seven aka Mini 850!
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Old 20th November 2018, 08:22 PM
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Injector?
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Old 20th November 2018, 10:06 PM
HPsauce HPsauce is offline
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Probably too slow for an injector (or valve?). At say 800 rpm a 4-stroke engine will be firing each cylinder 400/60 times per second, i.e. about 7.
It's not that rapid as I can count them while watching the second hand sweep on my watch.
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2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions, ski hatch retrofit; extended leather. Aftermarket DVB-T, reversing camera and full XCarlink (Bluetooth etc.).
2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (A much rarer model than a D2 S8 by the way!) Oh, and a brand new engine at just under 30,000 miles on the factory one!
Finally: gone, but not forgotten.....
1998 D2 PF S8. AgateGrey/Platinum. Every option (I think) except electric rear seats, tiptronic steering wheel, ski hatch, towbar & dimming door mirrors.
e.g. Cruise control, NavPlus/TV, Bose, GSM, Xenons, Solar roof, Parking sensors, Alcantara/leather everywhere of course. (internal dimming mirror added later)
1998 (very early) Ford Focus 1.8 Zetec; ABS/TCS, Heated screen/mirrors, Aircon, Auto-dim mirror, Leather, Trip computer, Cruise control, OEM Ford SatNav with CD changer.
And before that a lot of Rover 800s, a few oddities, a lovely Triumph Dolomite 1850HL with Overdrive and way back in my schooldays an Austin Seven aka Mini 850!
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Old 20th November 2018, 10:30 PM
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Hamster with a wooden leg?
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Old 21st November 2018, 12:45 PM
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I've certainly had a ticking sound when cold - a very discrete, sharp "tick" - which after running a few minutes goes away. Usually apparent after periods of non-use so its not always there.

Also, if its idling at 800rpm (13.3/sec) then the 4th (firing) stroke is around 3.25 per sec which was about the rate of my ticking. But CAN an injector "tick"?? I dont know - just thinking out loud, here!
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Old 21st November 2018, 12:54 PM
MikkiJayne MikkiJayne is offline
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If you take the engine cover off you can clearly hear the injectors ticking as they fire. Its not impossible for one to get louder than the others - you would hear a difference in the pattern.

A tick that goes away quite quickly is usually a hydraulic tappet. As they age they leak more static pressure when the engine is off, and can take a little running to warm up the oil to pump up fully. Not a problem if they quieten down quickly.

I've found they don't particularly like being parked nose-down either, for some reason, even thought that is the best attitude to prevent water ingress. My S8 can make quite a rattle and a cloud of blue smoke on cold-start when she's been sitting nose-down in the front of the workshop. Parked the other way round or flat she doesn't do it at all.
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Old 23rd November 2018, 06:34 PM
HPsauce HPsauce is offline
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Thanks MJ, that's probably it, I'm used to the noise of hydraulic tappets on older cars (especially Rover 800's of which I had quite a lot!).

I am parked in a slight nose-down attitude and do also often get a bit of blue smoke on startup, though overall oil consumption is zero!
__________________
2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions, ski hatch retrofit; extended leather. Aftermarket DVB-T, reversing camera and full XCarlink (Bluetooth etc.).
2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (A much rarer model than a D2 S8 by the way!) Oh, and a brand new engine at just under 30,000 miles on the factory one!
Finally: gone, but not forgotten.....
1998 D2 PF S8. AgateGrey/Platinum. Every option (I think) except electric rear seats, tiptronic steering wheel, ski hatch, towbar & dimming door mirrors.
e.g. Cruise control, NavPlus/TV, Bose, GSM, Xenons, Solar roof, Parking sensors, Alcantara/leather everywhere of course. (internal dimming mirror added later)
1998 (very early) Ford Focus 1.8 Zetec; ABS/TCS, Heated screen/mirrors, Aircon, Auto-dim mirror, Leather, Trip computer, Cruise control, OEM Ford SatNav with CD changer.
And before that a lot of Rover 800s, a few oddities, a lovely Triumph Dolomite 1850HL with Overdrive and way back in my schooldays an Austin Seven aka Mini 850!
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