Bad cam phasers can severely damage the solenoids, ECU and prominently the engine. You're driving down the street, and all of a sudden, your engine light pops on.

What happens when a cam phaser goes bad?

When a cam phaser goes bad, the Variable Control Timing (VCT) solenoids would be destroyed, and the engine control unit (ECU) would no longer be able to control the phasers. If not attended to, it can lead to valve timing problems which would eventually damage the engine.

How much does it cost to replace cam phasers?

Replacing cam phasers is not cheap. You can expect to pay anywhere from $800 to $2500 to get the job done by a professional.