S15 Silvia with a bad rattle

[nasx]

I just took delivery of a black 2000 S15 Qs (SR20DE) with full oem aero kit.
Darn it is a sweet looking car. Never saw one in person before.

But it has issues.
When cold it rattles VERY loudly at startup then the rattling all but goes away. When operating temp is reached, the rattling returns intermittently but not as loud as at startup. When revved, the noises seem to diminish unlike spun bearings that get louder when revved.

The stock oil pressure gauge is all over the place (jumpy needle movements and all) reading from normal at startup to zero when warmed up en then back up again, so I'm not sure it's working correctly.

My guess is thus the timing chain and/or tensioner, do the symptoms sound like the timing chain and/or tensioner to you, or should I still be thinking bearings?

If it's the tensioner, can the tensioner be changed without pulling the motor?
What about oil pump replacement can it also be done without pulling the motor? Thinking I might want to replace it just to be safe.

[MannylovesLian]

the noise is a bad intake cam gear!
You need to buy a new one.
I had the same problem.

[SoguRacing]

the noise is a bad intake cam gear!
You need to buy a new one.
I had the same problem.


you couldn't possibly state that as a fact. It's only a possibility. My guess is that is that it's a spun bearing or a bearing that's about to spin. If i were you I would check your oil pan for dents. if dents are found then replace. if rattling still occurs then check your rod bearings. As rod bearing wear you will see a decrease in oil pressure as more oil is slipping by the bearing. More than likely I would suspect rod bearings. It can also be piston slap....due to tapering of the cylinder walls. get it checked out. pull the valve cover off first and see if everything looks ok up top first.

[WoolyS14DET]

Take a vid and post on youtube and insert the link and let us listen

[nasx]

the noise is a bad intake cam gear!
You need to buy a new one.
I had the same problem.

How can I test or inspect this? Is this a common/known problem with S15's


you couldn't possibly state that as a fact. It's only a possibility. My guess is that is that it's a spun bearing or a bearing that's about to spin. If i were you I would check your oil pan for dents. if dents are found then replace. if rattling still occurs then check your rod bearings. As rod bearing wear you will see a decrease in oil pressure as more oil is slipping by the bearing. More than likely I would suspect rod bearings. It can also be piston slap....due to tapering of the cylinder walls. get it checked out. pull the valve cover off first and see if everything looks ok up top first.
No dents on the oil pan it's in great shape. I will pull the VC over the wekend. The car only has 45k miles and otherwise mint. Seems like the previous owner took good car of the car, so i'm hoping it's not the rods.

Take a vid and post on youtube and insert the link and let us listen

Will do that tomorrow

[SoguRacing]

also check for timing chain slack. it could be hitting the guide up top.

[Smurf_240SX]

Happend to my SR also turns out it was my Alternator Pulley bearing seized up. Noise would come and go. So that could be a possibility. Dont know about the jumpy oil pressure needle tho you might wanna check whats up with that first.

[nasx]

Happend to my SR also turns out it was my Alternator Pulley bearing seized up. Noise would come and go. So that could be a possibility. Dont know about the jumpy oil pressure needle tho you might wanna check whats up with that first.
Definitely not the pulley. but I'll try to get a mechanical oil pressure gauge hooked up to check the oil pressure.

This suck I only have the car less than 24hrs

[SoguRacing]

perhaps the oil pick-up/sump is loose.

[Tensor187x]

I'm gonna go with dents in the oil pan.
Starving that engine of oil.

[jackal264]

rofl spun bearings...

here are my 2 guesses. i'm leaning towards #2


you said your having oil pressure problems, your just getting air in the lifters and thats causing the rattle until the motor gets oil through the head.

secondly like s14 sr20's you have vvt. the vvt units tend to make noise when they get old. the unit engages at 1000 rpm. so once warm your idle will fall back to 850 and you will not hear it but every time you rev you should hear a click at the throttle body then the knock. you can also try inpluging the vvt. thats the easiest way to eliminate it as the issue.

my vvt makes noise from 1000-1300 rpm and at idle it is quite loud but it works just fine.


edit: intake cam gear as mentioned above is the same thing i am talking about b/c on an vvt motor the cam gear is the vvt unit. so like the very first post says replace it to et rid of the noise.

[nasx]

I'm gonna go with dents in the oil pan.
Starving that engine of oil.
Like I said above the oil pan is flawless. Thanks

[nasx]

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[nasx]

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[MannylovesLian]

Trust me man. it is the VCT gear/intake cam gear. i had the very same problem, knock on warm up, oil pressure flux, come and go once warm.
I took apart my whole block and replaced everything! EVERYTHING but that intake cam gear. i thought it was an oil pick up problem or oil starvation whatever. but then my mechanic told me to change the intake cam because that was all that was left to change. Well What Do You Know! That Was IT.

you can buy a used one for cheap, but you wont know if that one is bad. just buy a new one to save you the hassle. or you can just delete it and buy cam gears, but that would defeat the purpose of the gear and you will just have a S13 motor.

[nasx]

Tried getting a video of the rattling, but it all went away for several cold starts just light rattling once warmed up. Then when I did not have the camera it rattle like an angry diesel truck. A few cold starts later nothing again. removing the solenoid plug does not seem to do anything about the light rattling (sounds like a playing card running over bicycle spokes) once warmed up.

I'm looking into getting a cam gear? How much does a new one cost?

[fliprayzin240sx]

Either the VVT gear is fucked or the chain is tapping the retainer on top.

[nasx]

finally the video
YouTube - rattle sr20de (http://www.youtube.com/watch?v=1yIuSkvNpdg)
1yIuSkvNpdg

[nasx]

Replaced the cam gear, with a used low mileage one, (fingers crossed) and cleaned the tensioner with carb cleaner and WD40.
Rattle gone. I'm happy Thanks guys.