u/KlutzyNotice7312

2nd gen Scion tC, 2AR-FE, ~176k miles. I’m getting a P0302 only at about 80 mph in 6th gear around 3250 RPM under steady cruise. It doesn’t happen at 75 or 85 mph, and I can run through 3250 RPM in every other gear without any misfires. I can’t hear or feel it happening, but live data shows cylinder 2 accumulating misfire counts while cylinders 1, 3, and 4 stay at zero until it eventually sets the code. I swapped the cylinder 2 coil with another cylinder and the misfire stayed on #2. NGK iridium plugs have under 5k miles, and compression tested around 11 bar/160 psi evenly across all four cylinders a few months ago. The car has an HPS intake with a K&N cone, the MAF was recently cleaned with MAF cleaner, and I recently tightened all the intake connections. LTFT has been around +18% at light throttle for as long as I’ve owned the car and drops toward 0 as throttle/load increases; lambda is usually around 0.99. The P0302 started recently after using fuel-system cleaner and an oil cleaner/additive. Freeze-frame data also shows zero misfires on every cylinder when the code sets even though I can watch #2 accumulate counts in live data. Toyota says Injectors and PCV require removing the intake manifold on these cars, so I’m trying to narrow this down before tearing into it. Any ideas?

2nd gen Scion tC, 2AR-FE, ~176k miles. I’m getting a P0302 only at about 80 mph in 6th gear around 3250 RPM under steady cruise. It doesn’t happen at 75 or 85 mph, and I can run through 3250 RPM in every other gear without any misfires. I can’t hear or feel it happening, but live data shows cylinder 2 accumulating misfire counts while cylinders 1, 3, and 4 stay at zero until it eventually sets the code. I swapped the cylinder 2 coil with another cylinder and the misfire stayed on #2. NGK iridium plugs have under 5k miles, and compression tested around 11 bar/160 psi evenly across all four cylinders a few months ago. The car has an HPS intake with a K&N cone, the MAF was recently cleaned with MAF cleaner, and I recently tightened all the intake connections. LTFT has been around +18% at light throttle for as long as I’ve owned the car and drops toward 0 as throttle/load increases; lambda is usually around 0.99. The P0302 started recently after using fuel-system cleaner and an oil cleaner/additive. Freeze-frame data also shows zero misfires on every cylinder when the code sets even though I can watch #2 accumulate counts in live data. Toyota says Injectors and PCV require removing the intake manifold on these cars, so I’m trying to narrow this down before tearing into it. Any ideas?

2012 Scion tC with 168k miles. I'm at my wits' end chasing a weird handling issue. The car pulls/drifts right under acceleration, then when I lift off the throttle it will jerk/pull left and move the car over noticeably before settling, then pull right again when I get back on the gas. It does not do this under braking. Around 168k I did a clutch and 3 engine mounts with no immediate issues. About 1,000 miles later I developed a front-end pop, so I replaced the sway bar end links and outer tie rod ends, but the pop remained. After an alignment, about 400 miles later this throttle-on/throttle-off steering issue appeared. Last week I replaced both control arms, ball joints, and CV axles and got another alignment. The pop is now gone, and the alignment completely eliminated the steering issue at first, but after about 200 miles it gradually came back and is getting worse again. Outer tie rods are new (Moog), control arms are new (Mevotech), inner tie rods have only very slight play, and braking does not affect the symptom. Since alignments seem to temporarily fix it before it returns, I'm wondering if something is shifting, loosening, or changing alignment under load. Has anyone seen this on a tC or have ideas on what to check next?

2012 Scion tC with 168k miles. I'm at my wits' end chasing a weird handling issue. The car pulls/drifts right under acceleration, then when I lift off the throttle it will jerk/pull left and move the car over noticeably before settling, then pull right again when I get back on the gas. It does not do this under braking. Around 168k I did a clutch and 3 engine mounts with no immediate issues. About 1,000 miles later I developed a front-end pop, so I replaced the sway bar end links and outer tie rod ends, but the pop remained. After an alignment, about 400 miles later this throttle-on/throttle-off steering issue appeared. Last week I replaced both control arms, ball joints, and CV axles and got another alignment. The pop is now gone, and the alignment completely eliminated the steering issue at first, but after about 200 miles it gradually came back and is getting worse again. Outer tie rods are new (Moog), control arms are new (Mevotech), inner tie rods have only very slight play, and braking does not affect the symptom. Since alignments seem to temporarily fix it before it returns, I'm wondering if something is shifting, loosening, or changing alignment under load. Has anyone seen this on a tC or have ideas on what to check next?