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D2 - Engine Bay Everything under the bonnet

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  #1  
Old 16th March 2024, 01:05 PM
HPsauce HPsauce is offline
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Default Tapping noise from engine on cold start

Haven't run the S8 for a few weeks, started it today; fired up almost instantly despite a weak battery. Clear tapping noise from the engine heard all round the car outside though inaudible in the drivers seat.
Stayed for ages while I let it idle - checking/adjusting tyre pressures. Went for a short drive and it had gone on return.

Listening carefully it seemed to be at half the RPM frequency. So idling around 800-900rpm (13-15/sec) it was about 7 taps per second.

Any thoughts on what it is, how to narrow down the source and how significant it is?
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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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  #2  
Old 16th March 2024, 09:00 PM
donp38 donp38 is offline
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Default

I don't know these engines at all yet.
But that sounds like a hydraulic lifter sticking.
Sure someone will be along soon with a more robust solution /reason.
Kind regards
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  #3  
Old 16th March 2024, 09:04 PM
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steamship steamship is offline
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You raised this back in 2018, and MJ responded in post #6:

https://forum.a8parts.co.uk/showpost...97&postcount=6

Any other search result is generally about the startup rattle.
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2001 A8 D2 FL 3.7 Q - LPG Conversion, Engine: AKC, Gearbox:FBB, Colour:LY5X Aqua Blue pearl effect, Interior:WJ light beige/dark beige valcona leather with burr walnut inserts

My DIY jobs - Replaced alarm horn, Replaced Coolant Temp sensor, Updated RNS-D firmware, Installed Reversing Camera and Digital TV, Dashcam Installation, Retrofitted Rear Blinds, Auto-Dimming Rear View Mirror, Chrome Boot Struts

Sold! 2008 S8 D3 5.2 V10 - Engine: BSM, Gearbox:KLW, Colour:LY7F Suzuka Grey Pearl Effect, Interior:Black/Black with Silver/Black valcona leather with carbon atlas inserts, Bang & Olufsen, Heated windscreen, Soft-close doors, TV, DAB, AMI, Quad Zone, Auto Boot, Auto dim Mirrors, Keyless entry, PDC with rearview camera, AFS II Headlights

My DIY jobs - Fan Jet Windscreen Washers, Retrofitted Electric Side Blinds
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  #4  
Old 16th March 2024, 09:17 PM
HPsauce HPsauce is offline
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Well remembered, Sean. At my age you forget these things!

The engine has been in MJs expert hands since then so I thought I'd better ask anyway.

My old Rover 800s (I had almost as many of them as IT had S8s!) were very prone to this so I recognise the sound.
__________________
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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  #5  
Old 17th March 2024, 08:19 AM
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steamship steamship is offline
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Quote:
Originally Posted by HPsauce View Post
Well remembered, Sean. At my age you forget these things!
More like the benefits of Google. I just noticed that donp38 had beaten me to it.
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2001 A8 D2 FL 3.7 Q - LPG Conversion, Engine: AKC, Gearbox:FBB, Colour:LY5X Aqua Blue pearl effect, Interior:WJ light beige/dark beige valcona leather with burr walnut inserts

My DIY jobs - Replaced alarm horn, Replaced Coolant Temp sensor, Updated RNS-D firmware, Installed Reversing Camera and Digital TV, Dashcam Installation, Retrofitted Rear Blinds, Auto-Dimming Rear View Mirror, Chrome Boot Struts

Sold! 2008 S8 D3 5.2 V10 - Engine: BSM, Gearbox:KLW, Colour:LY7F Suzuka Grey Pearl Effect, Interior:Black/Black with Silver/Black valcona leather with carbon atlas inserts, Bang & Olufsen, Heated windscreen, Soft-close doors, TV, DAB, AMI, Quad Zone, Auto Boot, Auto dim Mirrors, Keyless entry, PDC with rearview camera, AFS II Headlights

My DIY jobs - Fan Jet Windscreen Washers, Retrofitted Electric Side Blinds
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  #6  
Old 17th March 2024, 07:16 PM
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RICKY D RICKY D is offline
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I fired mine up this week after several months and had the exact same noise. I let it idle for a bit and it got quieter but didn’t completely go away. Once I went for a spin around the block it was pretty much gone. That was on Thursday. I fired her up again today and there was no noticeable noise
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1988 E30 Coupe - Royalblau Metallic

2003 S4 Avant - Light Silver Mettalic

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