Alternator buzzing???

[dk05]

Ok, first off, my car just recently started throwing out the DTCs P0171 and P0131 randomly and it is missing very badly. I tried replacing the plug wires and plugs, that did not seem to help. But as I was changing the wires I noticed that there was a strange buzzing coming from the Alternator area. I wanted to be sure it was the alt so I unhooked the alt from the battery and it went away. Just a note, I was doing all this with the car turned off. I hooked it back up and right off the bat it started buzzing again. I don't believe this is normal...? Also when I was driving it I *think* the stereo made a odd noise through the speakers.... but it was not even turned on.... The charging system light does not come on and with the engine running I was testing @ 14 volts... granted that was not with anything on... Any ideas as to what may be the problem would be greatly appreciated. Thanks

[Juglenaut]

RE: Alternator buzzing???

Replace the alt. It may read normal voltage, but the alt could be low on amperage output..The alt could just bearly put out enough to keep stuff running...Does it get worse with an average load??

[dk05]

The car doesn't seem to miss any better/worse with everything on, I'm not even sure what the problem could be. The car is missing so badly I don't even want to drive it, and today it threw out P0300 on top of the P0131 and P0171. Also on a side note, the car stinks awful of exhaust and when I shut off the ignition there is a big rumble type of noise from the engine compartment and the muffler sputters, hard to explain it... If I hold the gas pedal perfectly still, the car revs up and down. Only thing that makes me think the alt could be the problem or at least part of it was the odd buzzing with the engine off. I have never heard an alt do that before so it seemed odd.

[geoffinbc]

Its buzzing because the regulator is fucked or about to be. Replace the alt or rebuild it if you want. They say it cannot be rebuilt but I have done it myself before its quite easy.

The other sputtering is a misfire or in correct firing order. A lack of ignition voltage may be causing a weak spark. Another question would be what plugs are you running. If you say Bosch then change them to Delco's and hang your head in shame. :P

[dk05]

Firing order is correct, checked it a few times. Tried it with Autolites and Delco's, neither made a difference good or bad.