Humming Part next to timing belt after alternator repair.

[RMDavis]

Hi -
A couple of days ago, the alternator died. Tried to make it home, but the pulley let go and took the tensioner and serpentine belt with it. I replaced all three today. (And for once, did not have an extra parts leftover ).

Engine fired right up and run for about 1 minute and then died. Now restarts and will run for at most 10 seconds and then dies. Exhaust smells of incomplete combustion / running rich.

Start poking around under the hood and noticed humming / buzzing sound from the top of the engine on the passenger side. This sound continues if the engine is off and key removed. Does not appear to stop until the battery cable is pulled.

Pulled the cover of the area next to the timing belt and isolated the sound to the device shown. Appears to be two of then. I pulled the power to the one closest to to the firewall and the sound stopped.

BadHummingPart.jpg (75.64 KiB) Viewed 439 times

What is this devices and would it cause to engine to experience the issues described?

[abscate]

Thats a CVVT solenoid, short for continuously variable valve timing,

If it is always getting electricity something is wrong, but I'm not sure it's the solenoid. The ECU controls the power in these cars.

It could explain the pooor running as it messes up valve timing if the signals are wrong

[RMDavis]

Thanks for this information!

In order to move the car out of the garage, I left the CVVT unplugged. The engine started and seemed to run just fine for the 2 minutes I ran it to move the car.

Does this suggest the CVVT is the issue?
How long may I run the engine without the CVVT?
Is this a dealer only fix?

[abscate]

You won't hurt anything but lose some power. You will get a check engine light from the lack of cam advance too, so that will have to be cleared.

You will need some with ViDA software to fix, so a dealer or good Volvo independent

[RMDavis]

Rats! Well at least I know what I need to do.

Really appreciate your assistance with this issue!

Ross