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Rattle noise and high RPM hesitation

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Hi everyone,

I'm experiencing some annoying issues with my S15's SR20DET.

I went to Germany a couple of days ago, and I made a top-speed pull on the autobahn (with an HKS SLD fitted)
The car was running fine, but when I reached about 6300 rpm in 6th, I felt like a power drop, so I slowed down.

From this day, I have a quite loudly rattle noise and high RPM issues.

The noise can be heard from idle. Pretty sure it comes from the top end.
The noise is like this video : http://www.youtube.com/all_comments?v=uyORsBWMfrghttp://www.youtube.com/all_comments?v=uyORsBWMfrg

Noisy from idle to 2500 rpm, after, I can still hear it (at a higher frequency), but not as loud.

The other problem is high RPM hesitation. Despite the noise, the car runs good until 5000 rpm.
Then, there are some small hesitations like misfire, and a real lack of power.
Pressure is à 0.6 bar max, and instable, whereas it was at a stable 0.9 before the problem.

So, I removed the valve cover to check what's happening.
No obvious problem, everything seems OK, no wear, etc
Some rockers have a little bit of lateral play, but I haven't found large play between the rocker and the cams.

Anyway, I bled today the lifters. There were some air bubbles in almost all of them.
After a test drive, the noise seems a bit quieter, but it's still there.
And the high RPM issue/lack of power is still present too.

I tested the VVT solenoid. It seems to work.
With a consult software, I tried to enable and disable it, nothing changes.
And anyway, the VVT has an effect only in mid range...
I don't think it's the cause.

What are your thoughts ?
Maybe a broken lifter ?
Can a bad lifter cause high RPM issues ?

My SR20 is stock, except an Apexi air intake, and a turbo back 3" exhaust...

Thank you !
 
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let me broaden your understanding, stock ecu, .9bar, stock fuel pump??? Stock intercooler??? extended periods of time above 5k.................. really really bad idea with a factory fuel map, can cause heaps of problems.

.6 bar and you would have been fine..... as the map understands .6 at 5k to the limit
huge risk of thin mix causing det and on the list goes

also, with all the extra heat being generated, hot thin oil = not enough coverage to bearings, you obviously haven't spun one


is the noise defiantly coming from the head? or the block, can you tell the difference between rod knock and lifter tick/VCT cam gear dieing

by the way your you tube clip does not work
 
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Almost sure it's from the head, and the bleeding of the lifters has definitely done something, but not for a long time :D
 
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if its defiantly a head noise, then the second thing you do (after bleeding the lifters) is replace the VTC solenoid, un plugging them does not give any indication it they are stuffed, you can put a 12v supply across them and they will still click even when they are not supplying enough oil pressure to the gear. If that solenoid is not working correctly it would explain why you had a power loss at high revs as the intake cam would start retarding back to where it sits in at idle due to no oil pressure being supplied.
 
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although just watching that clip now , it sounds like rod knock.... mostly due to the fact that thats a s13 engine that does not have VTC
 
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