Does anyone know what this slow ticking noise is?

[MaiaB 3]

I’m looking at buying this ‘07 e91 325i. 
 

I had a pre-purchase inspection done, it passed rather well considering the vehicles age. The one thing putting me off is this slow ticking, the mechanic wasn’t too sure what it was as he didn’t hoist the car up. It seems to slow to be lifter tick? 
 

Is this a ticking time bomb (excuse the pun) or just symptomatic of the engine not being warmed or driven much recently? 
 

Any help or advice greatly appreciated 😊

[*Glenn* 854]

Get a proper PPI with underbody inspection and diagnostic scan on all systems with a detailed written report

[MaiaB 3]

Thanks Glenn. Looks like I’ll have to get another one done. He ran diagnostics and did a semi-detailed report, but he didn’t know what the noise was or could potentially indicate.

 

 

[smiddy 76]

My wife's X3 N52 has same noise, is the fuel system evacuation purge valve solenoid.

The operation at idle is normal, the noise is from valve wear and should not be audible from inside vehicle. Removing solenoid  plug while car is running will/ should cease the sound.

Not a major fix or cost for new valve unit.

As Glenn rightly says, have full scan and check over before proceeding.

[MaiaB 3]

Thanks smiddy. Best description I have seen so far. I’ll get it properly inspected, but wanted some info to give me an idea of what the problem may be and where it’s stemming from.