Hey guys I've got a noise in my car that sounds pretty bad. The noise is a kind of rattling/knocking noise, that will speed up and get louder with engine revs. I have read a few threads about big end bearing noises, and some of it seems to make sense but other bits don't. Do big end bearing noises come and go, or are they constantly there? The noise in my car starts pretty much just after I get off idle (i.e. 1500 rpm or so) and continues throughout the rev range.....however The odd thing is that there is no noise at all if I am either lightly accelerating, or really sticking the boot in. I tried accelerating up to 4500 rpm and holding it in 2nd gear, and I found that I could hold the engine at any rpm with very light throttle and it was completely silent. If I accelerate hard, and then back off, the noise will fade in as I am backing off the accelerator and disappear if I take my foot off completely. Moderate acceleration causes the noise to be quite loud. Help!

Where in the engine does it seen to be comming from? Top or bottom? If its comming from the top then it could be a rocker arm or two that have worn on the rocker shafts. Anyone else?

grab ur powersteering pulley off the front of the pump. and pull it foward and backwards ? make a similar noise. make sure ur belts run 'straight' and that u got no bent pulleys. chek all the 10mm nuts that hold ur power steering i think it is pulley to the harmonic balancer..

Pipebom: It's not anything in the head, I've just put a new one on. It's hard to say exactly where it is coming from, it's somewhere down below but also I can hear it really clearly from inside the car. Ollie: I'll check that out now

My car makes exactley the same noises as Jordy describes. If I hold it it second and accelerate say above 2000 rpm u can really hear the noise but if u get above about 3000 rpm u cant hear it anymore. If I take my foot off the accelerator it goes away. A few people have said busted exhaust studs to me, if u find out what it is Jordy i'd be keen to know cos I think we have the same problem.

Hmmm I certainly hope not erin, because my noise is what I think a spun bearing might sound like My noise is louder and sounds hollower than busted exhaust studs, and it continues past 3000rpm (depending on throttle position). The noise seems to disappear when the engine is getting near to positive boost pressure (2 mmHg vacuum - 9 psi boost) . Do bearing noises disappear under load? Ollie I checked power steering pulley, etc. but no such luck I think it sounds more expensive than a loose pulley Some original photos have not been recovered yet.

a broken exhaust stud sounds like throwing a lug nut into a pipe and shaking it. what jordy is describing doesn't sound liek that. best to goto mech save urself the trouble.

My mechanic (when I need one) is my girlfriend's old man. He thought bearing noise too, but he has never seen an RB30 bottom end let go so he doesn't know exactly what it would sound like.