I recently discovered that the VQ38DD powering our D41 Frontier’s lack a built in vapor separator like other GDI engines. Instead, the PCV system simply routes crank case gases directly into the intake plenum via a short tube coming from the passenger side valve cover.
The issue with this, especially since fuel no longer washes the intake valves, is that the motor is prone to accelerated carbon build up. I know a catch can won’t entirely solve the problem, but it will help delay the process.
As such, I invested in a J&L unit designed for the Frontier. It literally took me less than 10 minutes to install the separator this morning while waiting for my daughter to get ready for school. It’s more expensive than generic cans you can buy on Amazon, but I didn’t feel like bending or fabricating brackets or measuring and trimming hoses. The can is also made in the USA so things like machining, build quality, and fittings are excellent.
Here are a couple of photos. Apologies for the poor lighting. I can take some better-lit pictures if anyone’s interested.
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The issue with this, especially since fuel no longer washes the intake valves, is that the motor is prone to accelerated carbon build up. I know a catch can won’t entirely solve the problem, but it will help delay the process.
As such, I invested in a J&L unit designed for the Frontier. It literally took me less than 10 minutes to install the separator this morning while waiting for my daughter to get ready for school. It’s more expensive than generic cans you can buy on Amazon, but I didn’t feel like bending or fabricating brackets or measuring and trimming hoses. The can is also made in the USA so things like machining, build quality, and fittings are excellent.
Here are a couple of photos. Apologies for the poor lighting. I can take some better-lit pictures if anyone’s interested.
