QuestionHi there again,
The noise comes from the engine compt. It a also only appears while driving because when I press the accelerator while parked the engine sounds normal. It maybe transmission related but I don't know. There was a service bulletin issued by BMW for a loud squeal but it expired in august of 2006. It called for reprogramming the transmission manually. I am still puzzled though because like I said before it only appears at a certain gas pedal position and I can go through it (the squeal) quickly by pressing the gas pedal down quickly and bypass the noise. Also it is regardless of RPM as soon as I press the gas pedal to that certain point it squeals. Also, do you know if the gas pedal is connected electronically to the fuel control unit or mechanical? The reason I am asking is because the "squeal" I am hearing sounds a little bit like a potentiometer arching (electronic interference) but it also sounds like metal on metal!?
Thank you for your help,
Heiko
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The text above is a follow-up to ...
-----Question-----
Hi there,
I have a 2001 BMW 330CI Coupe with about 72000 miles on it.
Engine and transmission compartment are bone dry and no leaks anywhere. But anytime I press the accelerator to a certain point I get this high pitched squeal. It only shows up at a certain accelerator pedal position and is regardless of RPM but it is getting very annoying since it has that extremely high squeal associated with it. Any ideas to what might be causing this? I can't pinpoint the origin of the noise but it can be heard outside and inside the car.
Thank you for your help,
Heiko H.
-----Answer-----
Hi Heiko,
It would be difficult for me to assist you here if you can not tell me where it comes from. Try having an associate do the pressing of the accelerator, open the front hood and position yourself there and try looking for the approximate location of the squeal. Front, rear, lower, upper, left side/right side ?
Usually high pitched noises are due to bad belts and pulleys
so you may want to check infront of the engine first (both tensioner and deflection pulleys are notorious for making noise).
After you have localized the noise, get back to me if you can.
Regards,
Tino
AnswerHello Heiko,
I guess your transmission is automatic since you mentioned a bulletin about programming. Most of the service bulletins relate to delayed shifting and hard shifting complaints. One bulletin deals with noise that can happen if the transmission had recently been worked on and the bell housing had not been properly mated to the engine using the dowel. Here, replacement of the dowel is needed if no other part seem to have been compromised. An expired service bulletin? Sounds interesting, but bulletins normally are superseded.
The throttle valve in your car is an EDK (electronic). Fuel signals are sent by the accelerator sensor and the EDK sensor to the DME (engine computer). I have not heard of arcing causing squealing of a metallic noise.
If it s a squealing noise, as I said before , it is usually the belt tensioner (specially if it is the mechanical type).
A metallic clicking noise can be due to the DISA valve/controller at the top left rear area of the engine
attached to the intake manifold.
Some really bad noise can be due to the VANOS, but this would be clearly in the top front of the engine. I am sorry that I am not there personally to help you pinpoint the noise.
Tino
