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Discussion Starter #1 (Edited)
Today, out for a day trip I noticed there is a rattle coming from the engine compartment. It occurs from 2.5 -3k rpm and upward. It is very slight but it can be heard under light throttle and revving at a standstill. I am unsure of any noise on full throttle due to background noise.
There is no noise on start up and cannot be heard under 2.5k. 45k on the clock, oil level fine. No codes
Searched and can only find chain tensioner but that shoud be heard at idle ?





Gervase
 

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A bit worried to say the beast... get it?

Could be minor valve tick which is unlikely or IMO probably just VANOS tick. At idle does she sound kind of like a diesel? If she doesnt now, she probably will soon, if its the VANOS.

Not an issue really. Can be mended (I just realized I, an American, said mended... thanks Top Gear) with new VANOS gears but it really wont alter the performance of the vehicle assuming it is the VANOS noise.

Take a video of it though if possible so we can ensure we have the right diagnosis
 

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Might sound stupid, but check your powersteering fluid level. When I did maintenace work, I forgot to fill mine up and it made a rattling noise cause the pump was empty.
 

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Discussion Starter #6
After researching, I feel it may be rod bearings :crying2:

Not sure I can take much more punishment, she may have to go !
 

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...definitely not normal. I doubt VANOS. Is it present under load at those rpms also? Hopefully some bracket or part is loose under the bonnet. I believe (but am not 100% sure) that rod bearings start making noises slowly and more progressively over time. Also, I believe the clue is that they make more noise under load and not with free revving but I could be wrong. Any others?
 

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Rod brgs knock when an unloaded engine is accelerated quickly, which is what yours sounds like. I hope I'm wrong.
 

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Discussion Starter #10
Yes, makes the noise under all conditions load and no load, above 2.5-3k. It was a bit hard to hear under full throttle yesterday but I'm not doing that anymore.
Rob, yes it's true, the thought is crossing my mind. I can't take the continuous problems with the car as it has to be mechanically perfect. Yes, it's 9 years old but with only 45k on the clock and the seemingly endless minor and now potentially major problems, no mind the obligatory vanos rebuild in the near future, I am giving some serious thought to binning it and going back to Japanese. Half an eye on GTR listings.


Gervase
 

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Sounds like mine did

Hi

Listening to yoru clip on you tube it does sound like the rattle I had which did indeed turn out to be rod bearings (at 56k miles in my case).

I would suggest you get it to Phil Crouch and have them inspected. You may be lucky and the crank journals may be undamaged. If so, its a relatively inexpensive fix. I suggest not driving it anymore.

A chap on this forum had the same noise as me but was lucky. Naturally, I wasn't and I had my bottom end completely rebuilt

Rgds

martin
 

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Discussion Starter #12
Hi

Listening to yoru clip on you tube it does sound like the rattle I had which did indeed turn out to be rod bearings (at 56k miles in my case).

I would suggest you get it to Phil Crouch and have them inspected. You may be lucky and the crank journals may be undamaged. If so, its a relatively inexpensive fix. I suggest not driving it anymore.

A chap on this forum had the same noise as me but was lucky. Naturally, I wasn't and I had my bottom end completely rebuilt

Rgds

martin

Thanks, planning on calling him first thing.

Gervase
 

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A chap on this forum had the same noise as me but was lucky. Naturally, I wasn't and I had my bottom end completely rebuilt

Rgds

martin<!-- google_ad_section_end -->
Can the crankshaft be removed with the engine in the car and the heads still on?

Unbelievable that they would go at such a low mileage. <!-- / message -->
 

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I know that the rod bearings can be changed from below by dropping the sump etc. , with the crank in situ. It tends to be the case that the main bearings are in good shape, its the rod bearings which seem to wear. There are several posts on this forum of people who have done just that.

I don't think it is possible to remove the crank though. If that's required its an engine out job I believe.

Rgds

martin
 
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