Mild Rough Idle Volvo D13

My truck burns more fuel while warming up until it reaches an oil temperature of about 160-170F. If it's already warmed up, it could be the 7th injector trying to get your exhaust temperatures up to burn soot, like a mini regen. 600k is usually around the time to clean the DPF filter.

 

Is it starting normally or does it take longer to start after it sits for awhile? Are there air bubbles in the return line of your passenger side fuel tank? If so, it may be an injector going bad.

 

At .9 gph to low for injector to go bad when it idles cold what do u mean by rough idle is it uneven idle can u see the rpm needle move up and down and fluctuate. Is engine brake working good.

 

What year is the truck and mileage

 

It's called "warm hold" mode.

The EBPV or Vanes are used depending on the year truck.

It provides load on the motor until it's warmed up and keeps it warm.

This is a good feature.

Raising the RPM disables the warm hold mode.

 

My it’s same specialty in cold wether

 

It's called aftertreatment for a reason. The exhaust is treated after it exits the engine. A 7th injector will not impact engine performance.

 

You are correct. At the time I posted this, I didn't understand the warm idle feature. A 7th injector will impact fuel economy, but I'm not sure if it's reflected on the dash. Maybe you know.

 

put a banana in the tailpipe and that would affect fuel economy too by creating more load on the engine, and the ECM would probably sense that. But that 7th injector is positioned in the exhaust stream so I wouldn't expect much effect, speaking from a common-sense standpoint. The "warmhold" feature was new to me. I investigated it and Volvo even discusses it in its specs on the D13, so it's a real thing. We were wondering why a vehicle we were test driving was shaking at 600 but not at 625 or 1000. I suspect the thermostat was stuck open, which caused the engine to run too cool, which caused the feature to come on.