Diesel sound, AKA the failing Variator.

(Information from Rein Douma)

Since the barchetta is designed by Fiat, there's at least one part that will always fail. With the barchetta it's the Variator, causing it to sound like a tractor when running idle. The failing of the Variator won't happen overnight but will slowly crawl in just to make sure you don't recognize it until when you finally do have serious doubts if the Variator is working properly you will find the warranty has just expired.

How to detect a failing Variator?

First of all, let experienced barchetta owners listen to your car, if they run away screaming you are sure to have a faulty Variator. If not, but they think the sound is suspicious, then the Variator probably has began the end of its lifetime. The malfunction starts with the cold engine sounding a bit rough at start up, the time needed for it to stop making that sound increasing day by day. After a certain period of time, mostly weeks, you'll notice strange sounds when decreasing speed. You'll hear the engine clatter but when the revs drop below 2500 rpm, the sound abruptly disappears like someone just switched off the noise. However it will come back when running idle. When your Variator has come to this point, you'll hear the diesel sound all the time when the revs are below about 2000 rpm. The sound level will increase until you find yourself having developed a driving style to avoid the diesel sound as much as possible.

Will it hurt my engine/have a bad influence on performance?

Fiat claims it will not hurt your engine. But hey, do you trust Fiat in this? Bad timing of the valves most probably causes the sound. The Variator is designed to give some overlap in the valve timing between the intake and outtake valves at higher revs. Since the performance of the car isn't influenced at all at high revs it's most likely the Variator is stuck in the 'fast mode'. So you get full power when needed and bad sound when idle. There's a little trick in the motor management system. Run the engine at idle. Very slowly rev up. At some point you will find the engine revving up itself until max rpm. It is said that with a healthy Variator the motor management does this around 2000-2500, and with a failing Variator at much higher revs.

Rein Douma redbarchetta@zeelandnet.nl

As this is a problem that almost every barchetta owner will experience during their enjoyment of the car it has been the subject of many articles and message board postings, below are just some of the links to these items.