What does this sound like to you?

gmasters · Post by **gmasters** » 18 May 2012, 11:37

I recorded some audio clips of my poorly idling Volvo. Two of them are the engine bay and the other is the exhaust. It is idling very poorly and I am wondering what could cause this issue? The only code I am receiving on my OBD is 121. I can hear a pop noise and when I put my hand on the intake it feels like it is backfiring into the intake. I took the off the hose that connects the exhaust to the intake but it still does it.

Also when installing the O2 sensor, are the 2 white wires interchangeable?

Your help will be greatly appreciated.
Engine 2

Engine 1

Exhaust

Thanks,
Garrett

Post by **JDS60R** » 18 May 2012, 16:04

Sounds like its running rich and/or has a vacuum leak

Post by **JDS60R** » 18 May 2012, 16:05

On a 4 wire sensor the two whites are normally the heater and can be inter changed.

gmasters · Post by **gmasters** » 18 May 2012, 17:46

Thank you for th input, the poor running condition turned out to be a faulty Idle control valve. Now I need to find out why it bogs down when I step on the gas.

Thanks,
Garrett