Hi Guys After a bit of advice on my ecotec Over the past month or so it has developed a slight metallic sssh sssh sssh sssh noise as I accelerate over 2000RPM not sure if that means big end bearing? (it seems to be coming from the rear end of the block) Also it seems to ping and rattle alot upon light acceleration. Does anyone know what could be causing this? Engine is serviced meticulously every 5000km with Penrite 20W-70 Full Mineral Oil. The engine still goes as hard as ever but just doesn't sound quite right and I really can't afford another engine right now. Engine is fairly stock apart from CAI, Extractors/Exhaust, Manifold/Plenum Spacer.
See I thought that too, but went over the exhaust and there doesn't seem to be any leaks. And this is more of a metal on metal noise than an exhaust leak noise There is also the pinging and rattling noise from the engine under acceleration which is definitely coming from the engine.....not sure if they are related though
If it's leaking near where the manifold joins the head it can sound like metal to metal - a sharp sound. Have you tried getting under and shaking the exhaust to see if anything rattles? The engine cannot ping (in theory the ECU stops that) so I'd guess the sound and rattling noise may be your ignition breaking down under load..possibly coils or DFI module. Check plugs leads are on the correct plug (they can get mixed up slightly and engine will still run. Also do a fault code test http://forums.justcommodores.com.au...22307-checking-error-codes-vr-vs-revised.html Finally check your harmonic balancer - see if it wobbles at idle and whether any of the rubber is splitting as this can make a rattle before it fails.
I just noticed that its knocking when I rev it (couldn't hear it out in the open, but in the enclosed shed it was very noticeable)
Could be your cat converter. They sound like marbles in a tin can when rooted. Have you used a stethoscope or a long screwdriver around the motor to pinpoint the rattle?
If you can hear pinging the knock/retard will cut in and will pull timing making your head go through the windscreen lol. Are you sure its ping?
Thats a good point, I haven't checked that I will upload a video tonight of how the engine sounds now. I rev it and it sounds ok but as the revs drop back down it has a huge consistent knock/rattle coming from the bottom of the block, makes a huge racket (can't hear it as loudly in the car but when I put my head under the car the noise became very distinct, hence me thinking more and more along the lines of big end bearing) Also don't think its the cat as its only a few months old (high flow stainless cat) but will pull it off and check none the less
Here is a vid (will need sound up loud) As you can hear its ok when I rev the engine but the rattle comes after revving. Upon further inspection it appears to be coming from the top end now so thinking maybe lifter or pushrod? Any ideas? The noise is alot louder in the flesh than in the video, would really like to get rid of it
Yep thats lifters. Do an engine flush, change the oil and add lifter free. If that doesnt help change the lifters. I'd also try and get an oil pressure guage on it and make sure the pressure is within tolerance.
