Friend's GTI sounds like a diesel when hot

[4Motioner]

I have a friend with a GTI that sounds like a diesel when the engine is hot. It's got an intake and a full cat-back exhaust.

We just opened the valve cover yesterday but found nothing out of the ordinary. Also did an engine flush and changed the oil and filter, but the noise is still there. It's only audible when the engine is hot. When cold, it sounds perfectly normal.

The sound seems to be coming from the right side of the engine from where the fuel pump is. Could this be a bad cam follower? Any other ideas?

 

[The Fed]

Cam follower, fuel pump, intake or exhaust camshaft, intake valve, exhaust valve, intake or exhaust cam bearing, intake or exhaust hydraulic valve cam follower, anything else in the engine that moves because sound travels. Start with the easiest to get to and continue as needed.

 

[CharlieMKV]

research "Dieseling"....that whats called i believe.

 

[The Fed]

^^^What do you call advice that's stupid?

 

[ROH ECHT]

PCV sound like this? Could be the rear check valve...
http://www.youtube.com/watch?v=t1RXH_jskkA

 

[CharlieMKV]

^^^What do you call advice that's stupid?

stupid.....:iono:

 

[4Motioner]

ROH ECHT, thanks for the vid. The PCV sound is definitely softer in tone than the sound my friend's car makes.

If I had to guess I would have guessed valve lifters, but they all seemed to be fine. We'll check the cam follower next.

 

[ROH ECHT]

ROH ECHT, thanks for the vid. The PCV sound is definitely softer in tone than the sound my friend's car makes.

If I had to guess I would have guessed valve lifters, but they all seemed to be fine. We'll check the cam follower next.

Yeah, I just remembered this sound being discussed before, and it was the pcv so I found this clip on the tube. When my follower wore through it made no odd sounds at all. Hope you find it...

 

[mikegabriel]

Can't say I've seen it on a MK5 yet but check the water pump. When the water pumps are on their way out in the MK3 / MK4 2.0Ls they start to sound like a diesel.

 

[alphabits]

If it is FSI and near the Fuel Pump, check that cam follower! Aside from that, the injectors in these cars are loud...could be an injector going out.
Just throwing ideas out there. Aside from the noise, are there any symptoms like fuel cuts or misfires?

 

[RevoGLI]

its the injectors. every volkswagen my family had has sounded like a diesel. especially this one now. its normal.

now it depends on the volume. of course mines not as LOUD as a diesel motor, but makes that cute puttering whilst idling.

 

[thechromecoyote]

^ Unless its as loud as that vid linked, its not the rear check valve. Most likely its normal. FSI engines are very "puttery"

 

[ROH ECHT]

Mine's nothing like the vid.