jlglr4
Full Access Member
I’m not sure. Your o2 graphs are not what I’m used to seeing, but both sensors seem to be oscillating. That doesn’t necessarily mean one is not bad (they can get slow to respond throwing off your fuel trims). But it’s not likely both would go at once. I think bank 2 fuel trims look wonkier than bank 1, so you could try replacing that o2 sensor - or just replace both sides while your doing it.
How many miles on the spark plugs?
Could also check the purge valve. If they fail open, they can create a rich condition by allowing fumes from the tank into the engine - especially if you top off the tank too much. It’s a black stiff plastic hose that runs along the drivers side of the engine with one end that dumps into the intake. With the engine off, disconnect it and blow into the end of the tube - should be closed with no air flow.
Leaking injector is another possibility, but I think you’d have some smoke at startup (fuel leaking into the cylinder after shut down burns off when you start it up).
The other thought I had was that the vibration is not really a misfire. Hesitation sounds like a misfire. Bouncing - not so much, but I don’t really know what you mean by bouncing. If engine mounts are failing, you might get some vibration in the engine at certain RPMs. If LCA bushings are worn, you might get some vibration at certain speeds. But this won’t cause any hesitation in power under load.
How many miles on the spark plugs?
Could also check the purge valve. If they fail open, they can create a rich condition by allowing fumes from the tank into the engine - especially if you top off the tank too much. It’s a black stiff plastic hose that runs along the drivers side of the engine with one end that dumps into the intake. With the engine off, disconnect it and blow into the end of the tube - should be closed with no air flow.
Leaking injector is another possibility, but I think you’d have some smoke at startup (fuel leaking into the cylinder after shut down burns off when you start it up).
The other thought I had was that the vibration is not really a misfire. Hesitation sounds like a misfire. Bouncing - not so much, but I don’t really know what you mean by bouncing. If engine mounts are failing, you might get some vibration in the engine at certain RPMs. If LCA bushings are worn, you might get some vibration at certain speeds. But this won’t cause any hesitation in power under load.
