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      07-28-2026, 07:27 PM   #1
sxychubles
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Rough start..maybe.

Relatively new to the platform so i'm overly sensitive to any new sounds or weird activity. This may be normal but would like to get y'all thoughts on it.

After sitting for 24 hours the car turns over a little rough in my opinion.
I recently changed injectors and spark plugs.

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      07-28-2026, 07:41 PM   #2
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The starter sounds a lil week but the startup and motor sound normal. Keep in mind a cold start does sound bitchen for like 30-40 seconds and then it simmers down to normal idle. Some people hate the cold start process but I kinda like it because It makes the motor sound rowdy to me.
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      07-28-2026, 07:51 PM   #3
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Quote:
Originally Posted by Scrippy View Post
The starter sounds a lil week but the startup and motor sound normal. Keep in mind a cold start does sound bitchen for like 30-40 seconds and then it simmers down to normal idle. Some people hate the cold start process but I kinda like it because It makes the motor sound rowdy to me.
It sounds bitchin if you know its normal, otherwise it sounds like its getting no oil and the bank account is getting emptied
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      07-28-2026, 07:57 PM   #4
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Quote:
Originally Posted by sxychubles View Post
It sounds bitchin if you know its normal, otherwise it sounds like its getting no oil and the bank account is getting emptied
So the S65 is NOT a smooth engine like mostly all of the straight 6 predecessors. The headers are stainless steal and noisy. When I traded my 335 in for my M3, I swore I had an exhaust leak at 25,000 miles but no. This motor has been called a sewing machine for good reason.
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      07-28-2026, 07:58 PM   #5
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Dude! I've been thinking I had a exhaust leak this entire time. It drives great which gives me peace of mind.
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      07-28-2026, 08:29 PM   #6
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It’s literally in the owners manual that the car sounds weird and metallic at cold start. In the quick start guide I believe.
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      07-28-2026, 08:32 PM   #7
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Yeah probably, will need to read it, but the community with years of added experience provide me with more peace of mind.
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      07-28-2026, 09:15 PM   #8
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My quickest/best advice to you as a new owner….

1-Let it warm for a minute or two if you can.
2-Drive chill (under 3k) until up to temp and then have fun.
3-5k oil changes religiously.
4-Get ISTA,INPA,laptop & K/D-can cable and learn to use it.
5-Do as much as you can yourself.
6-Enjoy the shit out of this platform.
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      07-28-2026, 09:22 PM   #9
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Quote:
Originally Posted by Scrippy View Post
My quickest/best advice to you as a new owner….

1-Let it warm for a minute or two if you can.
2-Drive chill (under 3k) until up to temp and then have fun.
3-5k oil changes religiously.
4-Get ISTA,INPA,laptop & K/D-can cable and learn to use it.
5-Do as much as you can yourself.
6-Enjoy the shit out of this platform.

Thanks for this! Just replaced water pump, ps pump, ac compressor, alternator, valve covers, nrw vanos covers, control arms, wheel bearings, short shifter. Next will be dropping subframe and replacing all suspension components. Bought the car to learn how to work on cars and trying to restore it back to it's previous glory.

Been using tis for all repairs. ISTA would be great but haven't really had a need for it just yet. Would have been helpful for the transmission fluid.
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      07-28-2026, 09:33 PM   #10
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Quote:
Originally Posted by sxychubles View Post
Thanks for this! Just replaced water pump, ps pump, ac compressor, alternator, valve covers, nrw vanos covers, control arms, wheel bearings, short shifter. Next will be dropping subframe and replacing all suspension components. Bought the car to learn how to work on cars and trying to restore it back to it's previous glory.

Been using tis for all repairs. ISTA would be great but haven't really had a need for it just yet. Would have been helpful for the transmission fluid.
Oh shit, sounds like you’re pretty squared away. Just got the shit scared out of you by some noisy hydraulic lifters on startup. Yeah every once and a while it happens. I am nearing 300k and it hasn’t blown up yet, so that should give ya a little piece of mind.
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      07-28-2026, 09:38 PM   #11
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Yeah my main concern is the longer than usual crank and slight stutter on startup. My only comparison is the g82 which starts up without hesitation. Also considering the fact that this platform is allegedly plagued by failing fuel pumps. Waiting for the revised fuel sensor to come in.

But yeah the noisy motor at cold start always gives me a pause, especially after doing all the recent work that I, who is not a mechanic, did.
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      08-05-2026, 11:05 AM   #12
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It’s possible to have a bad injector out the box. Usually from my experience when a car has a rough start when it sits overnight it’s just unburnt fuel from an injector leaking. You can always remove the rail with the injectors still attached to the rail and place the injectors in small individual clear containers and see if any of them leak overnight. With the injector harness disconnected you can prime the rail with key on engine off. I would rule this out out. I know it sounds like a lot of work, but it’s really not.
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      08-05-2026, 11:43 AM   #13
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Quote:
Originally Posted by B58 View Post
It’s possible to have a bad injector out the box. Usually from my experience when a car has a rough start when it sits overnight it’s just unburnt fuel from an injector leaking. You can always remove the rail with the injectors still attached to the rail and place the injectors in small individual clear containers and see if any of them leak overnight. With the injector harness disconnected you can prime the rail with key on engine off. I would rule this out out. I know it sounds like a lot of work, but it’s really not.
This is great! Will do. So the idea is to prime it once and then leave overnight?
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      08-05-2026, 01:55 PM   #14
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Quote:
Originally Posted by sxychubles View Post
This is great! Will do. So the idea is to prime it once and then leave overnight?
Technically yes because it will eventually start to leak when it sits if you do have an injector problem.
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      08-05-2026, 09:51 PM   #15
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going to do it on saturday night after the rain stops. will report back. Thank you!
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