Jump to content
SAU Community

Recommended Posts

there is a strange loud knocking noise coming from around the engine, the more u rev it, the louder it gets, it sounds like metal tapping against each other, car seems to drive fine and idles normal and doesnt blow any smoke.... the noise is gettin worse and worse, gets louder each time i drive it or thrash it

its a 94 r33 gtst rb25det

it also knocks when on idle and not reving

is it my bottom end gone? needs a rebuild?

Edited by 5ky
Link to comment
https://www.sau.com.au/forums/topic/127268-engine-knocking-noise-rb25det/
Share on other sites

to confirm where the noise is coming from you can get a stethescope and put it up against your block or head to find out for sure (your mechanic will know where its coming from anyway).

it could be your bottom end or it could be a dodgy lifter, but from what you're explaining it sounds to be your bottom end :action-smiley-069:

time for a regrind.

  • 4 years later...

another possibility could be the ball bearings in your alternator. will have no effect on the driveability of the car. mine did this once. when they come loose they make a hell of noise flying around inside the alternator and will soon kill your alternator altogether and battery goes flat and engine stops. just a possibility

  • 2 years later...

Mine's doing the exact same thing, 99% sure the noise is coming from the intake cam area. been told it may be a lifter as the car still drives well so wouldn't have thought it would be a valve spring or valve, but any advice identifying the problem would be greatly appreciated.

Another possibility is the bearing on the viscous clutch for the fan. See if the fan has play in it.

I just put a s/h one on my car and the bearing was stuffed, it sounded really bad. If I hadn't had just put it on, I would have thought I'd done a big end bearing!

You could wobble the fan a few mm side to side.

Replaced with another unit and it's silent now!

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • When you crank your car, and hit it with a timing light, can you see a steady crank timing?
    • Oh, forgot to add, A few months ago I was getting mixture codes and the car was using crap loads of fuel. You could smell the unburned fuel in the exhaust, it was crazy strong. Economy was over 17.5 l/100 and usually around 19. I smoked the engine and found a leaky CCV hose which I replaced and then I replaced my two pre cat O2 sensors, I also replaced the MAF. This fixed my mixture codes and improved my exonomy but I'm still 14 - 15 l/100 when pottering about town so something is still amiss. Throttle response is much better and it has more pep but I'd like to know why it's still so thirsty (and I'm hoping that whatever it is gives me a bit more poke).    
    • Car is on factory injectors/z32 maf/ q45 throttle body/ z32 ecu with nistune 
    • Hello all, currently finishing up a rb25 swap into my s14. Having issues with starting, car has spark (confirmed by pulling a plug and watching it spark), has fuel(confirmed by checking pulse/voltage at injectors all spark plugs are soaked in fuel). Car cranks over and pops into the exhaust with a heavy fuel smell but no attempt to start or run, I have torn the timing cover off and triple confirmed timing, turned the CAS in multiple spots both directions, attempted to start with coolant temp and maf unplugged, checked my fuel lines and made sure they weren’t backwards, checked voltage at cas/injectors/coilpacks, made sure all the grounds in the harness are connected and added a few grounding straps (1 from chassis to block, 1 from chassis to head, and 1 from chassis to igniter chip) I am getting stumped here. As a last ditch effort I made a full grounding harness tonight that’s going to run from the battery and add an extra ground from the battery onto the coil pack harness/igniter chip/ intake manifold/ Wiring specialties harness ground/ and alternator. I’m hoping maybe the grounding harness will fix it here but posting here to see if anyone has any other ideas on what else I can check. My fuel pressure is unknown right gauge will be here tomorrow.  IMG_3206.mov
    • yeah I was shocked when I checked my spare OEM on and as below that's how they come from Nissan. (side interesting note new NEO gearbox and replacement park lack the brass bush on the tips and its just all alloy) unsure about damage to the box currently back at 1110 to be pulled down/inspected and selector fork replaced as he built it previously and given the never before seen failure on his billet forks he is replacing it under warranty. He said he has used always OEM the keyway tab without issue for years so it could be an unlucky coincidence. I did talk to him about the sharp corners and stress concentration too. Re: hard shifts i got 7+ years out of the OEM one and the fork itself failed not the keyway. so could be bad luck as I said or an age thing + heat cycles in box and during fabrication of billet?
×
×
  • Create New...