I have two CEL codes. P1537 Manifold Runner Control Stuck Open and P0442 EVAP Control System Small Leak (0.040") Detected. Do these go hand in hand, I can't notice any changes except a slight power loss. Where do I start? Also before anyone mentions it, I have a new fuel filler neck and cap, and the cap is tight.

 

 

Thank you, I'll check that, let you know what it does

 

Turned out to be a split lower hose, both codes gone and i took a 30 mile drive after clearing them.

 

I had the same problem when I got my truck. I am glad it seems to be fixed.

 

Yeah, after reading a bunch of other sites, that hose splitting where it bends seems to be a common issue.