Power Loss After Warm Up?

[cbenez1]

Hey all, I've got 2 2004 V6 auto Xterras. One blue with 115k one silver with 162k. Problem im having is the blue one loses ALOT of power after it reaches operating temp. No miss firing or odd noise just has very little power. Under full throttle its pathetic but seems fairly normal under light throttle application. TPS was swapoed with the other Xterra and caused no change to either truck. Had an evap code but I found the vacuum leak and cleared the code. Hasn't come back in a week but the lack of power persists. Any ideas ?

 

[cbenez1]

Anybody have an idea?

 

[TerryD]

Do you have a scanner where you can pull up the long term fuel trims?

You might have a fuel issue caused by a failing O2 sensor.

 

[cbenez1]

I don't have one but I can probably get access to one. I'm assuming the idea is "failing" but not completely failed so not tripping a CEL?

 

[TerryD]

Yeah. Tending toward lean of you're not noticing issues with fuel consumption. Maybe drive it till it's showing the issues and pull a plug to check it? Or unplug an O2 sensor or MAF when it's doing it to see if that improves it running on a base fuel map rather than the learned trims.

 

[jcco]

I know nothing about first gen, but have you checked the pcv valve(assuming that there is one)?