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Discussion Starter #1
Occasionally when I start the STS there is what sounds like a noisy lifter for the first 20-30 seconds.
After that the noise goes away completely.

Is this normal?
I've had cars where it's normal to hear it when it's cold, is the same true of the Northstar?

The car is 5 years old with only 16,000 miles on the clock.
I don't know for sure, but I suspect, that it is running Mobil 1 oil which is rated 0W-40. The oil level is fine.
 

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2008 SRX-V8, 1991 Eldorado
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Occasionally when I start the STS there is what sounds like a noisy lifter for the first 20-30 seconds.
After that the noise goes away completely.

Is this normal?
I've had cars where it's normal to hear it when it's cold, is the same true of the Northstar?

The car is 5 years old with only 16,000 miles on the clock.
I don't know for sure, but I suspect, that it is running Mobil 1 oil which is rated 0W-40. The oil level is fine.
What you are hearing may not be a lifter noise at all but likely a belt/tensioner noise.
 

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What your are hearing is piston slap aka cold carbon rap. Carbon builds up on the underside of the head from "babying" it. When the piston reaches TDC it makes contact and the piston rocks on the wrist pin causing the skirt to "slap" the cylinder wall. The cure is simple and fun. Take her out and whoop her aka a dose of WOT. Put her in 2nd gear, plant your foot firmly on the floor and hold it there til you reach about 70 MPH. Then release it and let it back down to 50 or so. If you see a lot of carbon coming out of the tail pipe, do it again til you don't see it anymore.
 

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Ranger said:
What your are hearing is piston slap aka cold carbon rap. Carbon builds up on the underside of the head from "babying" it. When the piston reaches TDC it makes contact and the piston rocks on the wrist pin causing the skirt to "slap" the cylinder wall. The cure is simple and fun. Take her out and whoop her aka a dose of WOT. Put her in 2nd gear, plant your foot firmly on the floor and hold it there til you reach about 70 MPH. Then release it and let it back down to 50 or so. If you see a lot of carbon coming out of the tail pipe, do it again til you don't see it anymore.
Although I do agree with the fun aspect of removing carbon deposits, isn't carbon deposit most pronounced with warm engine knock as opposed to cold engine start?
 

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Yeah, my '99 with 47K mileage does that also. I seem to think that there are quite a few out there that do the same thing. It's a ticky ticky ticky kinda thing and goes away soon after start. I'm not too concerned with it really yet it would be good to know what it is. It may be mechanical, in the valve train maybe, it may be electromechanical such as an injector, or maybe a test and set due to some designed system, these cars are sophisticated in that respect and are constantly reviewing sytems positions and adjusting for them. It's like the ride level compressor we here testing right after turning the ignition switch. I dont buy into the piston slap or tensioner theory because it gives off no decernable "feel" to it. I'm also not one to think "Oh well, they all do it" either. There are so many things it could be and so many things it couldn't be in my eyes because of the engineering. These cars aren't '51 Chevys anymore if you know what I mean. So, bottom line for me is that although I recognize it exists, I'm not about to start tearing something apart only to not find the source.
lry99eldo
 

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Discussion Starter #7
I agree.

That's why I thought I'd ask before assuming it was a noisy lifter that was just slowly pumping up.

It could be injector noise, but injectors are normally noisy all the time. Mind you some can be louder than others. The Ford Racing ones I fitted to my Camaro sound like valvetrain clatter (you can even hear them with the hood shut), but it's just the injectors.
 

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91TexasSeville said:
Although I do agree with the fun aspect of removing carbon deposits, isn't carbon deposit most pronounced with warm engine knock as opposed to cold engine start?
Carbon can cause noise in a cold engine just as well as a warm one. Not saying it's your problem, just addressing the question.
 

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91TexasSeville said:
Although I do agree with the fun aspect of removing carbon deposits, isn't carbon deposit most pronounced with warm engine knock as opposed to cold engine start?
Nope, cold start ups. Check out the Technical Archives (top left of this page) and read the section "Occasional Full-Throttle Acceleration Is Good For Your Engine".
 

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Occasionally when I start the STS there is what sounds like a noisy lifter for the first 20-30 seconds.
After that the noise goes away completely.

Is this normal?
I've had cars where it's normal to hear it when it's cold, is the same true of the Northstar?

The car is 5 years old with only 16,000 miles on the clock.
I don't know for sure, but I suspect, that it is running Mobil 1 oil which is rated 0W-40. The oil level is fine.
How long has the oil been in there? If it's been long, I'd try changing the oil first. If that doesn't work you might try this...

http://www.wynns.uk.com/contextra/documents/Hydraulic%20Valve%20Lifter%20Treatment.pdf

It looks to be a newer version of the old Wynns Engine Tuneup. WET used to work wonders on some tough cases like the flat 6 Corvairs. I'm no advocate of "snake oil" cures" so I offer this FWIW. Your car. Your decision.
NS
 

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Funny that changing oil has been brought up because I just did that two days ago. The ticking noise is not ALWAYS there, at least to my ear or concentration at that moment, yet I did think of that and listened for it after changing the oil. It was there, so at least with my engine fresh oil didn't elimininate it.
I really don't know what it is and I only brought up injector as a possibility because it is electromechanical and may be a cause.
lry99eldo
 

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... I seem to recall using ATF to cure carbon buildup in older engines ... and marvels mystery oil to cure noisy lifters ... not sure if I'd treat my caddy to either of those "cures" though!

Steve
 

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SteveThefolkie said:
... I seem to recall using ATF to cure carbon buildup in older engines ... and marvels mystery oil to cure noisy lifters ... not sure if I'd treat my caddy to either of those "cures" though!

Steve
They used to use oatmeal to seal up radiators in tin lizzys too, but I wouldn't recommend it :)
 

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My Mark VIII used to do that. It was a thing called a "hydraulic lash adjuster", it is basicly a lifter. I don't know what kind the northstar uses, but it might be that.
 

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I agree.

That's why I thought I'd ask before assuming it was a noisy lifter that was just slowly pumping up.
Cold carbon rap sounds just like dry lifters. I'm still betting that is your problem. Oils today are much better than they were 20 or 30 years ago. Very unlikely you have a sticky lifter.
 

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Could be me but, a "ticking" lifter sounds nothing like piston slap or carbon knock. Even the average shade-tree mechanic should be able to tell the difference between them pretty easily. If it sounds like a top-end "ticking", it probably is a lifter. Especially if it goes away within a few seconds. Try an oil change. You may have the wrong oil in it, or a malfunctioning oil filter. Most utilize an anti-drain back system that keeps the filter from emptying at all after engine shut-down. If this is not working, you aren't getting proper oil pressure up to the lifters immediately. If the oil is the wrong viscosity, it will do the same thing, starve the top end parts momentarily on cold engine start-up and produce not only significantly increased engine wear but...noise from the lifters etc. momentarily.
 

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Katshot said:
Could be me but, a "ticking" lifter sounds nothing like piston slap or carbon knock. Even the average shade-tree mechanic should be able to tell the difference between them pretty easily. If it sounds like a top-end "ticking", it probably is a lifter. Especially if it goes away within a few seconds.
My personal experience with my '97 Deville was, when it did it, it sounded like a lifter(s) to me. Then again, I don't hear these sounds very often so I could well be wrong. All I know is that it went away after about 30 seconds and after a dose of WOT, it did not return for a long long time. When it did, symptoms and cure was the same.

As I said, oils today are so much better than they were just 20 years ago. You just don't hear about sticking lifters like you used to "in the old days". That is why I tend to discount the lifter theory and the oil change or Marvel Mystery oil fix. Just my $0.02.
 

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Discussion Starter #20
I only got the car a few weeks ago.
The receipts that came with it were for servicing by a local garage who claim to use Mobil 1 0W-40 in all the cars they work on.

Now, according to the manual this is the wrong weight to be using but in theory it is thinner so I would have thought it would circulate quicker?


I have no idea what brand of filter is on there, I haven't looked.
What brand do you recommend?
 
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