19 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCH996 engine rattle noise at cold start
Leading reported evidence
Use two and there was a slight wiggle
Performed · outcome unconfirmed
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
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Discussions that performed work without a confirmed outcome
1
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0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
I was using just one hand and didn't feel any play, then used two and there was a slight wiggle.
Leading evidence: 'Use two and there was a slight wiggle' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'slight play in my water pump' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Check exhaust system' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that suspect a cause
1
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Suspected cause
I'll know then if it was the slight play in my water pump for sure pulley then.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
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Suggestion
For the rattle, have you checked your exhaust system?
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
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Suggestion
At least you should check for a loose spark plug and a rattling cat.
Disconnect belt - as macster has said in other posts
Suggestion or failed attempt
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
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0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
I'll do that and also disconnect the belt - as Macster has said in other posts.
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
19 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
1 acknowledgements have no verified action link; they do not establish a repair result.
Outcome without a verified action link
No change in ticking - I wasn't really expecting any change.
I have a 1999 911 Carrera Coupe and at cold start it makes kind of a rattle noise, plus engine ticking for about 10 seconds. My coolant and oil levels are good. The rattle right after ignition start is brand-new and a bit worrisome. Thanks for you help!
Usually that is a sign of chain rattle in my experience not necessarily with the M96 specifically however. Often can mean a worn or broken chain guide. On some motors that is not a big deal ad doesn't need to be immediately addressed. Not sure about how the M96 fits in that area however.
that's the other thing it could be. If it does it less after a fresh oil change, likely lifters. If no change at all could point to chain guides, but still could be lifters too.
Well, when was the last time you changed your oil? If it's due or almost due, that may be it. That's for the ticking.
For the rattle, have you checked your exhaust system?
Try this... Pull fuse C4 (fuel pump), spin the engine over for 10 seconds or so - you can even watch for the oil pressure gauge to rise, put the fuse back in and see if it cranks quitter.
On mine its the bank 4-6 chain tensioner that hangs upside down and leaks down after a few hours. I bought all three but that one is the hardest one left to replace on my 01 C2.
For this to appear out of the blue suggests to me it needs to be checked out by a qualified tech, someone you trust and rely on for input for the most serious of car related issues. While I don't think it is serious a bit of caution right now can possibly save you a ton of worry and grief and two tons of money.
I mean I could repeat the stuff about the possibility of the oil being overdue to be changed and cover the issues about selecting the wrong oil -- not that you have I'm just saying sometimes owners come here with weird ideas about what oil to run (5w-30 or something like that...) -- and how these engines are just a bit noisy etc., but I think you should have this listened to by a tech.
I'm even going to be a bit more conservative and advise you flat bed the car to a tech for a listen. I know, I know, but I'm just not willing to risk thousands of dollars unnecessarily to save a hundred bucks.
Of course it is up to you. Oh, and whatever you decide at least avoid the temptation to recreate the noise again and again and have every neighbor give a listen, unless your favorite trusted tech is your neighbor.
Have you experienced this personally? I have an engine tick on my 993. The first oil change I did with the car was with Brad Penn (one of the recommended oils for that car). No change in ticking - I wasn't really expecting any change.
The next oil change I did was with Mobil 1 (a 15W-50 and 20W-50 blend). The ticking was gone for about 1500 miles but then came back. My guess was it must be lifter related and you're the first person I've heard with similar experience.
My 1999 996.1 has a rattle, knock, tick during a cold start. 48,000 miles, 0W-40 Mobil 1, 30F outside. Sometimes it sounds like a rod knock, sometimes a chain rattle. Here's a video from yesterday:
http://www.youtube.com/watch?v=Z5IrhKTYEcc
You can pinpoint the noise by jacking up the car and using a mechanic's stethoscope to probe around. At least you should check for a loose spark plug and a rattling cat.
I'll do that and also disconnect the belt - as Macster has said in other posts.
It is a little disconcerting that so many of these 911s sound the way they do when cold. A lot of folks say that these noises are "common," but that doesn't mean that common is "normal."
Please update if you find the cause. My car makes a very similar noise for 10-30 seconds after startup, but my car is in storage, so I have not had time to diagnose this myself.
Thank you!
When you have the belt off, grab the water pump pulley with both hands and really really tug hard. I was using just one hand and didn't feel any play, then used two and there was a slight wiggle.
My car is currently at shop getting new clutch (including flywheel), AOS, redesigned RMS, EPS IMSB solution.
I pick it up tomorrow. I told him to look into this noise at startup for me while he has it. I'll let you know what he finds.
If my shop doesn't figure it out, I'm changing the water pump myself in the next week or so. I'll know then if it was the slight play in my water pump for sure pulley then.
I finally pulled the serpentine belt and determined that it's not any of the pulleys. The noise is still there. I guess it sounds like chains to me, so maybe I need new tensioners.
There are a lot of engines that have lifter rattle on startup especially if they sit a long time between starts. My 996 does it on cold starts ifbit sits a few days. If I'm driving it for a few days multiple trips and the oil and lifters don't have time to drain and pump down, nonstartup noise. I feel this is one of the disadvantages of a boxer engine compared to a V or inline. Lifters in a V or inline will retain more oil, but their disadvantage would be its likely dirtier oil.
I'm not certain but worn timing chain guides and chain rattle would probably be quite a bit louder and sound more random and less steady than lifters.
If if I ever have to replace the AOS or get to some major maintenance, I feel replacing the chain tensioners would definitely be worthwhile.
That is unfortunate. Mine still seems to be correlated with weather when it comes to volume and length of time that it runs noisy. When the weather is hot it starts quietly, but any days that dip into the 40s for temperature and the car makes the rattle/tapping sound. Not quite the same sound as scored cylinders, but scary nonetheless. For example, today was 55F and I had the rattle for 1-3 seconds and nothing right on startup, so I would think it is the chains. Car has had this sound since August of last year and when I took it in for inspection this April the sump and oil was clean as a whistle.
Well, upon further review, a lot of folks that have had this issue with noise, and they have replaced one or both tensioners, even IMSB and other items that were replaced such as chain pads, and they still had the noise.
So, I shouldn't have been so quick to say "tensioners" because I'm not sure that's it. Sometimes it sounds like a rod or piston knock, sometimes it sounds like lifters and valves.
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