I have a 2007 Nissan Xterra with 180,000 miles on it.
Recently had one of my catalytic converters clog up until the vehicle wouldn't run. I didn't see any warning signs because I recently purchased it for a 2nd vehicle to commute to work. After I had that fixed, I noticed that I was burning A LOT of oil, like 5 quarts in 1000 miles. Changed pcv valve and now I just have to change a heater outlet that I broke while changing pcv valve.
My question is, is there any additive or maintenance I should do, for issues like excess carbon build up, oil sludge, etc.? I had it running for a couple of minutes after I changed it and is saw a lot of smoke, but I don't know if that was from built up good or not.
Thanks, Steve
Unfortunately 5qts/1000 miles = worn out engine. The smoke you see is the oil burning and the cat converter was probably clogged because of the oil burning as well.
Hopefully you didn't pay much for that Xterra. That engine's definitely shot. You're practically doing full oil changes every 1,200 miles by burning it. My 1999 Ranger has almost 100k miles more than your Xterra and it goes through around a quart every 5,000 miles. The carbon buildup is from the motor burning oil, and unless you want to pay thousands to replace piston rings, valve stem seals and basically everything else in the way, there's nothing you can "pour in", to fix it. I think Lucas makes an additive to try to slow down burning, but that's just a band-aid and not a great one.
You can probably get another engine in the junkyard if you like to gamble, as Scotty says, then have that put in. If the place will let you, do a wet and dry compression test on the donor engine before you do all that work to make sure the engine seals are good.
Most people I know completely ignore the little $5 PCV valve until it's too late. Replacing it at every oil change will make your engine last a lot longer.
Do a wet/dry compression test to verify the internal condition of the engine. You will probably find the rings are worn out. If that's the case the best way to salvage the situation will be a low-miles used engine, either junkyard or JDM.
Hmm... I don't get it. The selling point was looking at the maintenance records. Routine maintenance done like clockwork.
I bought the car for a commuter so I don't rack up miles on my other car. I've only put about 5000 miles on it.
I DID purchase an extended powertrain warranty, which does cover rings and valve seals.
As Chuck suggested, get an independent mechanic to do a wet/dry compression test and document the results. That proves how worn out the engine is, and whether it is the rings, valve guides (or both).