Crazy terrible noise under my intake manifold 3.0 with video

[FastEddie313]

I shot a video while it was happening but it doesn't sound as grinding in the video as it did in real life..

https://youtu.be/RRPON_0qsQQ


Something under the intake manifold was sounding like an electric motor with a bunch of stripped gears, the engine was NOT running in the video.

It is not the little water pump there, I thought it was the electric throttle motor with gears stripped out but my throttle works fine now.
I also think it might have been the idle air control motor under there but my idle seems to be fine now too..

GF turned the key to start it but didn't even crank and just made this noise..

The noise stopped and then it started and drove fine..

Sometimes if I remove the battery or something it will not crank until I lock and unlock it a few times and try starting it a few times then it will crank and start..
It seemed to do this this time, turn key but no crank, but made this horrendous noise I have never heard before.

Any ideas?

[andrewwynn]

Aux water pump is right down there. If it threw a blade or bearing blew it could sound like that.

I had to jump start yesterday and could hear the pump clear as day key on engine off. I got back into the car before I noticed if the pump shut off over time if I didn't start.

Find the pump and unplug it will give you definitive answer.

[andrewwynn]

https://share.icloud.com/photos/0N5E...DjTw3RA_A#Home

[FastEddie313]

Originally Posted by FastEddie313

It is not the little water pump there

I really thought it was NOT the aux water pump but now you have me questioning my recollection..

My aux water pump has needed to be replaced since I bought this car but I just haven't replaced it yet. I have known for a long time that it does not work..

I get no continuity through the pins of the aux water pump and it does not respond to direct +12v last I checked but maybe it vibrated just right to start working terribly again..

I really thought this new noise and associated vibration was coming from under the intake manifold by the throttle body deep enough to where I couldn't reach all the way to it but maybe I am wrong and it was this water pump coming half way back from the dead..

I have had inpa codes the 2ndary MAF on the emissions air pump (though it blows good and valve works I think the MAF on it is dead) and a code for the aux water pump, checked the aux water pump and found it to be an open circuit.


I checked for codes with my generic scanner yesterday but only got 1 BMW specific code that the generic scanner did not know.

I guess I will drag out my INPA setup today in a little while and see if that can give me any new information..

Can you think of ANYTHING ELSE under there that could make this noise?

[andrewwynn]

My wife's SAP is defective and whines horribly for 90s every cold start but that doesn't run until you start the motor.

Unplug the aux pump you'll know immediately


Sent from my iPhone using Tapatalk Pro

[FastEddie313]

INPA shows nothing, not even a repeat of the aux water pump code. Only 2ndary maf still.

This no-crank no-start and noise only happened the one time and has not happened again..
But it was scary..

[andrewwynn]

Command the aux pump on and see if you hear it or not. I think as you guessed it just lined up just right to start once.