OcUK & Cutters Rolling Road Day 19 @ Powerstation (Tewksbury) - Saturday April 25th 2015!!

I'm surprised - assuming it's not off camera - that it looks like there is no air blower assisting with cooling on the dyno runs....?


And Damn shame Gibbo, seems a poor show especially given you didn't want the limit raised.

Is the tuner offering any fiscal assistance to you? Seems to me it's his raising of the Rev limit and then telling you to rev it out that's resulted in this...

Edit: I hope you've struck lucky with the loose sensor...



Have a listen to these, once engine has run a couple of minutes I can't hear anything untoward, not even with my head next to the bottom of the engine.

Cold start

After couple of minutes running

Blips to 4000rpm
 
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Sounds a bit knocky on cold but find on warm up. Try change the oil to something a bit thicker to see if it cures that?

Great pics guys.

Don't get thicker than 10-60W and it was fresh in last week. :)

Hard to know if that is how they sound from cold or not as that is first time I've ever put my head under the car from a cold start, but warm video was literally two minutes later so nothing was upto to temp yet , otherwise could not hear it and these things can sound like a bag of spanners on a good day and hard to tell if its vanos or engine noise.
 
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Gibbo it doesn't sound right to me, sorry to say. But aren't the engines in M3's incredibly tappety like Honda engines anyway?

Yeah all the tappet noise they make is normal, that's the vanos, typically sound like bag of spanners/sewing machines.

Trying to see if a mate who knows more what to listen for can come take a listen, but putting the temp probe back in the exhaust cured the rattle we were all witnessing when revs dropped after revving.
 
I winced a little at the first one, the latter two sounded ok to me. *

I wonder if your just (and quite understandably) hearing things after yesterday's scare you'd otherwise not give a second thought to? Many engines sound somewhat iffy when listened to close up from underneath or directly under the bonnet.

I've just had a listen to my 530i whilst doing its daily fluid check, it sounds rather noisy with the bonnet up and my head next to the cam cover, not so from within the car with the bonnet down and driven normally.

By all means get a second opinion (indeed a third!) I sincerely hope you've just had a false alarm.

* Caveat. I am by no means in any way qualified and for all I know it could be goosed or absolutely sublime! :o :D
 
I'm surprised - assuming it's not off camera - that it looks like there is no air blower assisting with cooling on the dyno runs....?

Powerstation has a huge blower system integrated into the dyno room, theres like a chimney at one end blowing air out the bottom, and an extractor setup at the rear by the exhausts. Plenty of air but no visible fans!
 
Gibbo I made a little video clip to make you feel better :p
This is what a motor which has a spun big end sounds like..

In fairness 2JZ (no ****) is a sturdy unit, I drove it like that for 10k miles without a problem :p
 
Gibbo I made a little video clip to make you feel better :p
This is what a motor which has a spun big end sounds like..

In fairness 2JZ (no ****) is a sturdy unit, I drove it like that for 10k miles without a problem :p


Yeah makes me feel better, mate just took a listen and said his M3 sounds the same from cold, trying to get a mechanic mate come take a listen with a scope before I risk actually driving it again.

But the lose sensor was certainly cause the horrible gravel/rattle type sound when revs dropped. But I just remember when I started it last night for the first RAC guy it did sound quite knocky, but when it came of the truck it sounded fine and it seems fine now.

Problem is I am now paranoid.
 
Do you guys think its a good idea to drop the oil and see if I can see what looks like any metal fragments/glitter/tinsel almost in appearance in the oil?

I guess if not I can just put the oil back in.
 
Do you guys think its a good idea to drop the oil and see if I can see what looks like any metal fragments/glitter/tinsel almost in appearance in the oil?

I guess if not I can just put the oil back in.

That was going to be my next suggestion. No harm in doing so. Will also put your mind at ease somewhat.
 
I think you are pinning your hopes on the sensor/ wiring too much there Gibbo because what I heard when you arrived back from a test drive was no random rattle, it was a consistent regular tap, just like a big end.
Second to that, the car reacted as a big end failure would upon application of light throttle rev blip.
Thirdly it reacted as I would expect a big end failure to sound after prolonged engine off/ cooling off and then initial rattle at start up.
Thirdly it is reacting as I'd expect a big to react in the initial stages of failure AFTER start up from cold... i.e silent, as the engine oil is thick and can supply good boundary lubrication/ pressure.
As much as I'd like to say, take it for a blat to heat it back up and have another listen, I think this would be detrimental to the engine if it was indeed the beginnings of a big end.
Rock <> hard place really, I must say.
Might be better to pull the sump and inspect what's in the bottom of it! If there is a load of brass coloured swarf then pull the big ends anyway. Hell if the sump is off, may as well fit the arp rod bolts and new shells anyway, certainly wouldn't be a backward step in doing that!
Yes, possibly a fair cost if it wasn't the issue but I guess on balance, the other side of the coin is that the cost will be massive if you do spin what turned out to be impending failure of one!
 
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...Id also add that some of these 'tuners' maps are not that firm on their rev limits, read of cars hitting 8400 when set to 8200 limit for example, so your 8500 might have been 8700 or worse. My advice is get it checked out by an M specialist before you start to put any more hard work on it.
 
Gibbo when was your car built, what was the exact production date?

Feb 2002 and it did have the rod bearing recall as I checked. :)

I think the oil filter tells the story:

IMG_2543.jpg


The oil which came out the pan was relatively clean, hardly any glitter in it, but look at what ran out the filter, looks very glittery and unless I am wrong I suspect that is metal shavings?

I guess now its a case of get the bottom end of and just hope one of the shells have not spun.....
 
Feb 2002 and it did have the rod bearing recall as I checked. :)

OK, that is what I was thinking. A friend of mine span a shell in his CSL and got a new engine on warranty. Not a common fault, but there have been a few over the years. His was used hard on track and over 60K miles if I recall correctly.
 
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