Power loss

Nissan3161

Bought an X
Location
Ohio
Hello I have been lurking on here for a little while trying to find a answer to my problem and I can't seem to find anything so I figured I would ask. I have a 2000 Xterra se v6 that seems to me like it is slowly losing power I understand it wasn't very powerful to begin with and I have added some weight to it 31in mt's and a RLC front bumper plus a 2in body lift and pml probably isn't helping either. My problem is even with all those parts installed (they were all installed within approx 6 month time span with the tires being the newest addition) it felt fine for a few months after all those parts were installed now suddenly I'm struggling to reach 55 or 60 mph even at wot it won't do much more than 65 that to me just doesn't seem right considering I've owned it for almost 2 years now and it has been fine up to about 2 months ago it started to get worse my power is down and I struggle to get 10mpg driving mostly in town I was getting 15 doing the same driving I am now with all those mods installed 2 months ago. I have been trying to determine the best course of action to take to go about figuring out what my problem is and I'm tired of finding answers that just sort of beat around the bush.
A little history for you plugs, wires, dizzy, timing belt, head gaskets/intake manifold gaskets and plenum gaskets all have about 10,000 miles on them and the only code I am getting with the scanner is p0505 idle air control valve.
So my questions are as follows,
1. Is the p0505 code the problem the code showed up after I did the body lift strange thing though I had the body lift off for about a month and code went away reinstalled bl and code came back truck idles fine so I'm not sure what the problem is there I haven't found anyone else with that issuenthat did the diy bl
2. I also was told by a friend who is somewhat mechanically inclined and knows his way around a car that it is possible that maybe my cats are clogged which could possibly be related to my power loss issue. So I was thinking about getting dt headers and getting rid of the cats any thoughts?
3. If I'm driving at say 45mph and I put it to wot it almost seems like it's not kicking down a gear properly (auto trans with fresh synthetic fluid and filter change) I put it to the floor and the rpm goes up but the speedo doesn't lol it almost sounds like the truck is struggling or gasping for air I have a snokle and a k&n drop in filter I'm not sure if that is the problem but The snokle was installed before I started having this problem.
The reason I'm asking is because I want to go to WENT this September and it's about a 6 to 6 1/2 hour drive from my house and Im not going to go if I can only go 45mph and get 8 mpg lol sorry if I rambled on a bit I my have forgotten something trying to get everything out of my head that I have been thinking about. Thank you for any help you can provide and ask any questions that you need to ill answer them to the best of my knowledge, thanks again Kevin
 

TheFauxFox

Titan Swapped / SAS'd
Founding Member
Location
Huntsville, AL
Based upon the final observation, check your trans fluid while running. If its not kicking into the right gears, or if there is delay, you could be low. I know you said you changed it out, but do you mean and drain and fill or a flush?
 

Intender

Wheeling
Location
Lewisville NC
Sounds like a trottle position sensor to me. Could be idle air control but that should go away once the truck warms up. Sometimes you can adjust the throttle position sensor and fix the problem sometimes it needs replaced. If by some chance you had it off for any reason I would say thats the problem for sure. Its the black box on the side of the throttle body. Two Phillips head screws hold it on and there are some groves for rotating it for adjustments. Turn it the wrong way and you get stuck in too high of a gear and it wont downshift. Too much the other and it will shift too soon. Cant help with which way to turn it since its been a long time since I touched mine.
 
Last edited:

Nissan3161

Bought an X
Location
Ohio
I haven't had that off recently but I can go turn it a little bit each direction and see if I notice a change and report back
 
Top