Only Chain Guide Noise? or more...

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240nspec
Posts: 111
Joined: Thu Apr 10, 2008 4:47 pm
Car: 1991 240sx Hatch KaDe

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Car runs decent except for at the range from 2-2.5k, there IS power loss within this specific range of rpm. Both Acceleration and Deceleration are Effected (as well as a no load condition ~Neutral).

2 videos:

In Video: I suspect chain guide problems, quite evident in this video, 2-2.5k problem not as clear.

Vid1: http://www.youtube.com/watch?v=iwjV4iZ2fRI

In Video 2: In the garage the noise is abit more amplified, after idling, Some out of gear 2-3k revving. Notice the buzz, rattle, and almost a gurgle type noise.

Vid 2: http://www.youtube.com/watch?v=8llzfqezuxM

History:

Oil does need to be changed soon, however I don't feel this being the cause of the problem. Oil levels have been checked. So Check Engine, or Check Oil (Which I'm assuming is both a pressure and oil level check light? correct me if i'm wrong) So I pass on that.

It's just when driving any gear, any condition cold start to hot, it's consistently replicable. Noticeable power loss at this range however once passed in rpm you feel the greater acceleration change. Clutch does not slip.

There was one weird accident that happened the previous day. Drove all day got near 6 o' clock and while driving 45-50mph the car began to become unstable. The rpm gauge the sore left to right with no change of throttle. All gears and rpm's where affected, Engine cut out twice while in motion, (my suspicion fuel or fuel comp) after parking, letting sit briefly restarting seemed fine. Has not happened since then (2 days ago)

My overall solution / plan of action would be a rebuild. Hitting the 140xxx Mark. If this is the best solution, or if is not please let me know, any help would greatly be appreciated.


danielsan
Posts: 349
Joined: Tue Apr 08, 2008 7:41 pm
Car: 1991 240sx coupe SE

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sounds like the upper chain guide, if you have not removed it then do so. the noise should be gone. pretty much your engine sounds just like mine except for the guide noise (i removed my upper guide)

as for power loss im dealing with that too. i think i have narrowed it down to low fuel pressure somehow, maybe a clogged injectors, line or weak pump?

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240nspec
Posts: 111
Joined: Thu Apr 10, 2008 4:47 pm
Car: 1991 240sx Hatch KaDe

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What im trying to figure out is that it is making excessive noise specifically in that rpm band while having power loss within that rpm band. It seems to me like a mechanical issue in the block or head. the previous problem with the cut out, I truthfully think that was a fuel problem. I'll run a little injector cleaner, perhaps seafoam it.

blackmagic
Posts: 468
Joined: Mon Feb 12, 2007 3:28 pm
Car: 1995 nissan 240sx se w/ rb26dett
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Hey man The noise in the first video is lifter shims. My girls car did the same thing I had to replace the shims. If you have a magnet pop your valve cover and make sure you cam lobes are facing up so its not compressing you valve and connect the magnet to the valve and lift up and down if theres alot of travel then im correct. try adding more oil and see if it changes the noise. if that doesnt work then u will need new shims and they get expensive. first yull need to get a gaping tool they sell them at autozone for like $3 or so and you need to find the exact amount of gap you will need by placing the tool inbetween the valve and the cam keep adding more pieces of the tool to the gap untill it wont take anymore but isnt jamed in there. try searching some more on it. but yeah that 1st video is most definatly lifter shim noise. it sucks

blackmagic
Posts: 468
Joined: Mon Feb 12, 2007 3:28 pm
Car: 1995 nissan 240sx se w/ rb26dett
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O and yes you will have power loss because the valve will not be compressing all the way.

kouki__monster
Posts: 4
Joined: Mon Dec 06, 2010 11:00 pm
Car: 1998 Kouki S14

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Hi, i know this is a necro.. but after hours of searching for posts this sound in the youtube video is the exact same as mine..

I know about the two upper timing chain guides that should be removed, and have the tensioner checked up

Was wondering what OP did to fix his noise? (if hes still around)

And do others think that the removal of the two guides would solve the sound in the first video? Thanks

kouki__monster
Posts: 4
Joined: Mon Dec 06, 2010 11:00 pm
Car: 1998 Kouki S14

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Bump, anyone? desp for some tips

Anyone know what the solution for this noise would be? Or anyone know how the OP fixed it? Thanks

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darens13
Posts: 1317
Joined: Fri Dec 28, 2007 6:30 pm
Car: '93 240sx, '90 chevy 1500, '49 dodge pickup

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i had the same noise. i removed the guides and threw them away, no more marble in the tin can noise.


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