1997 Nissan Pathfinder Rough Idling

[A1218]

Im feeling a slight roughness from the vehicle at idle. Feels more prominent when its cold and warming up, but once it warms up its better but you can still feel something. No misfire or rpm dropping either. It idles steadily around 650 to 700rpms in drive and 750 to 800 rpms in park.

Sometimes it would go a little lower to 600 when parking or stay closer to the 650 area with lights on rather than 700. I guess that is just due to extra load.

A few weeks ago I did some engine work: fuel injectos (hitachi), knock sensor (hitachi), fuel rail to intake rubber seals, IACV, intake manifold gaskets (Nissan), cleaned intakes, all new coolant hoses that are accessible with the intakes off, fixed a slight coolant leak from the thermowax element, clened throttle body, and new egr gasket.

When i was done I bled coolant system, set base idle with tps disconnected to 850rpms, and set tps to 0.46v whcih is within specs. I then did a closed throttle relarn with the key on and off procedure.

This roughness i'm speaking of was present from before, but thats not why i did this job, it was due to a warm restart stumble that occurs everytime after sitting for 30 minutes. A little over a month later and so far it seems to have went away. As for that roughness, its still there and possibly a little more prominent?

The only code I have is a p1441 code that comes on and off and could never get rid of, but thats not impactful to engine performance. And aside from that work I have new plugs (nissan), leads (ngk), and distributor (nissan) all of which are a year and some old.

Does the idle need to be kicked up a bit more? Timing need to be adjusted?

Or is this all normal

[mdmellott]

I would get the cause of that EVAP system fault code tracked down and fixed once and for all. Whatever is causing the P1441 code to get flagged may likely be the cause of your rough idle as well.