"Interesting" beep when putting foot down

[Alexander 0]

Cheers fella. It is at just over 2 bar at 2000rpm, just when at idle it's very low. I'll search out that other thread and start worrying in case it's something more serious!

[Dub_nut_g60 0]

Edit the Bently says minimum 2 bar at 2000rpm at 80 degrees, and there's another thread on here about G60 oil pressures with some other useful info in. Dub_Nut_G60 started it I believe.

 

and as if by magic

 

As your gauge in the car is saying almost 0 i would suspect the pump.

 

My buzzer and light came on when i held revs between 2 and 3k, changed pressure switches to no avail, next though was pump and garage also confirmed, but when they dropped my sump they found bits of my big end bearing in there, the bolts holding No.1 cap and sheared and were blocking the oil pickup. Car still drove well and pulled like a train which didnt point to a dead bearing!! always had plenty of oil in it etc... But it meant new engine time.

 

Not trying to worry you!! but bear it in mind as theres always potential for it.

[Alexander 0]

Ulp...

 

Well I'm not going to get wound up, it doesn't sound like exactly the same symptoms you have (buzzer goes off at high RPM/high boost, with no warning light - pressure looks normal at mid-revs) but I'll whip it into my mechanic to see what he thinks. Going to be a bit nervous about driving it in the meantime mind you, so I'll try not to until I get the problem fixed. Cheers for your help!

[Dub_nut_g60 0]

Ulp...

 

Well I'm not going to get wound up, it doesn't sound like exactly the same symptoms you have (buzzer goes off at high RPM/high boost, with no warning light - pressure looks normal at mid-revs) but I'll whip it into my mechanic to see what he thinks. Going to be a bit nervous about driving it in the meantime mind you, so I'll try not to until I get the problem fixed. Cheers for your help!

 

 

Probably best not to drive it unless really necessary, especially as a bad pump can only be bad for the engine.

 

See what the mechanic says, fingers crossed for you.

[Alexander 0]

OK thought I'd update this thread in case anyone finds it in a search for a similar problem:

 

In a nutshell, gave the car an oil change and the problem has gone!

 

The car had a new oil pump in 2004 so I kind of ruled that out, and oil pressure was actually OK (settling down to 2 bar under load, just above zero at idle once the engine got up to temp). So I'm putting it down to old oil. Be interesting to see if it starts doing it again when this lot of oil gets near changing time.

[ProdigalSon 1]

OK, a really leftfield suggestion...

 

Could it be that the ribbed V belt for the charger is slipping and 'shrieking' (for want of a better term) when you're caning it? :scratch:

 

Reasons being:

 

i) At WOT, there is no recirculated air to 'help' the charger to spin, so it is being forced by the engine to compress air without any assistance (unlike when it is on part throttle)

EDIT: your sig says you have a deleted boost return - so your charger will always be spinning without assistance from pre-compressed air... scratch part i) !

ii) If your oil feed is/was poor to the charger, it might have further internal friction to overcome as well as the air's resistance to being compressed

iii) If you don't have a wide V belt (often fitted with the 68mm upgrade) or worse still no toothed pulley + belt, the friction/resistance of the charger to spinning could exceed the friction offered by the belt, causing it to slip and chirp at you?

 

These would all be factors when driving hard with your foot to the floor. Perhaps the change in oil (and filter) has improved things now, but they may reoccur in time...?

 

Just some ideas in case it does happen again and the oil pump is not the cause :wink:

 

My money was on the wastegate initially, as it makes a sound like an old kettle with a whistle on the spout :D Would love to know what it is when you've nailed it! :thumb right:

[Alexander 0]

Thanks for the reply dude (actually just been reading your G-Werkz thread about your satin silver - good reading!)

 

Interesting you should mention the V-belt as it's just had a brand new one, although it was making the noise before and after it was fitted. It's a puzzler! I just kind of assumed that old oil wasn't getting up to the pressure it should on WOT, causing one of the (possibly old and on-its-way-out) pressure senders to complain. I'm pretty sure it will come back, and if I get a definitive answer I'll post it up!