intake pop / electic motor noise underintake manifold

[F_R_O_G]

trying to work out a few kinks in this car and found when idling the intake manifold will make a poping noise in a consistent pattern every 5 secs or so at idal. i don't know if this is related to a electric motor noise coming intermittently from under the intake manifold behind the alternator. I haven't driven this car for a few months btw. any ideas?

you guys saved me from pulling the motor and doing the heads, alldata doesn't even tell you about the coolant bleed valve so when the coolant started coming out the reservoir i just about shat myself

 

[chris2523]

what year, any codes, etc.

 

[slowmkviii]

A soft popping coming from the air box is usually a miss

 

[Sapperfire]

IAC can sometimes makes some strange noises too.

ALLDATA is ok, but since I can't have both I went with Mitchel 1, much better info on certain things
They both have their little faults thou

 

[KStromberg]

Frog, there is nothing behind the alternator underneath the intake manifold that would make any electric motor noise. The noise only sounds like it is coming from there because aluminum causes sound to travel and tends to give a false sense of the actual location of where the noise is originating. A stethoscope would come in handy for you. I have experienced that same kind of noise from both an idle air control valve and even a previous alternator that was going bad on me. The alternator noise was also, oddly enough, intermittent until the alternator finally crapped the bed within the next month.

The popping noise sounds like a misfire. Put your ear right up to even ON the airbox. Can you hear the pop?

 

[UltimateSVT]

Feels weird calling someone else "FROG" on this forum.

 

[F_R_O_G]

it's a 97, no codes.

i did use a stethoscope to find where the noise was coming from. i way thinking a runner control but if there's no runner control back there then probably the alternator. i'll take the belt off and check.

maybe it's just the dynamics of the intake that make it so loud. because it sounds a louder then a "soft pop" but not a loud pop. if that makes any sense. i'm worried i have a sticky valve


and i'm the OG FROG

 

[Savage Henry]

Sounds to me like sticky IMRC butterflies or a lean misfire popping back up through the intake. What do the ST fuel trims look like?

 

[KStromberg]

What do the ST fuel trims look like?

He'll never know unless he gets his hands on a device that is capable of datalogging.

 

[Sapperfire]

Sounds to me like sticky IMRC butterflies or a lean misfire popping back up through the intake. What do the ST fuel trims look like?

If hes backfiring through the intake, he's got some SERIOUS issues.. not likely

 

[F_R_O_G]

always hated it when i never got the solution for the problem.

noise was the alternator
pop was the IAC valve