New Jeep Renegade - traded from a Jeep JK

Hey CTdjradio, Have you been able to take your Renegade to your certified FCA dealership to have this issue diagnosed?

 

Nope not yet...I'm thinking this is just the way it's supposed to sound.

 

That seems to be a characteristic of the MultiAir valvetrain. My 1.4 turbo has that same ticky, almost diesel-like idle, as does the 1.4 MultiAir in my wife's Fiat 500. It's a technologically amazing valvetrain, but it is noisy at idle.

 

Yeah that's the consensus im hearing.

 

My 2.4 l rene is loud too but i feel its normal . the engine in my girlfrrinds 2015 honda fit is just as annoying and i took it back a few time to make surel it was fine lol.

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For you folks new to the direct injection game, you're probably just hearing the fuel injectors pulsing (opening/closing). Unlike older injection systems that had ~100 psi in the fuel rails, DI systems have about 2,000 psi. They're fantastic because having the fuel effectively vaporize directly in the combustion chamber rather than atomize before the intake valves (in the intake manifold), with all else being equal, runs cooler and more efficiently (as in, it burns more of the fuel). All else is not equal however, and that's why we get to enjoy higher compression ratios than ever before. Before, boosted engines were 8.0:1-8.5:1, now they're almost universally 9.5:1, where naturally aspirated engines once were. NA engines are running 11.0:1, at least, and on cars like Mazda Skyactiv stuff, around 13:1.

It's great technology, however, since they have so much pressure in the rails, the fuel injector valve has to be so strong and operate so precisely and quickly that now you do hear them ticking kind of loud at idle.

 

When you accelerate it almost sounds like somethings dragging in the rear as well. Strange sounds lol

 

I don't believe either of the USDM Renegade engines uses direct injection.