Buzzing noise from inside the engine bay (1993 Q45)

[Infinitiguy19]

I posted about this a long time ago but never got an answer.

But when I press the throttle 1/4 of the way down or 1.0-2.0 volts on the TPS I hear a buzzing noise from the engine bay and I can't seem to be able to narrow it down.

It does this in all gears and when the ignition is on (I cant hear it when the engine is running because of the added engine noise).

It might be the EGR Solenoid above the EGR I THINK and I am not sure.

Please help.

Also would this have anything to do with the TPS?Because the A/T comp isn't reading the closed throttle position switch.

[Q451990]

It should do it when you move the throttle body while you're under the hood too. The only difference is the cable. I haven't heard of this before... a mechanic's sthescope might be your best bet.

The TCU that won't read the closed throttle position switch is your good one, right?

Heath

[Infinitiguy19]

I will try that stethoscope.

And yea I have 2 different ECU's and they both read the same.

(The 1994 Q45 Cali ECU Actually works while the car is on, So I assume the TCU to be good as well.)

[Infinitiguy19]

It should do it when you move the throttle body while you're under the hood too.

Heath

What causes the buzzing noise?