This AI-generated draft has not been independently verified for your vehicle. Confirm engine, trim, build date, tool fitment and torque specifications against the relevant service information before buying tools or starting work.
On the 10th-gen Accord the upstream sensor is a wideband air/fuel ratio sensor that lives right at the exhaust manifold or turbine housing. Mechanically it is one threaded sensor and one connector, so the job is simple in theory - the difficulty is entirely about reach and heat. The hybrid's naturally aspirated 2.0 gives you the best access, the 2.0T is a reach from below, and the 1.5T packs the sensor into the tightest pocket of the three.
The mistake people make is buying a generic "oxygen sensor" because a P0420 popped up. P0420 is a catalyst efficiency code and usually is not the upstream sensor at all, and a universal splice-in unit will not correctly drive a wideband A/F circuit. Buy the OE-style sensor by VIN, work on a stone-cold engine, and use the slotted socket so the pigtail never takes load.
| Item | Type | Product search |
|---|---|---|
| OBD2 scan tool Code reader with live data / freeze frame Confirm the fault is the upstream (Sensor 1) sensor, not the downstream one, and clear codes afterward. | Required | search retailer |
| Floor jack 2 ton minimum Lift the front end for underside access on 2.0T and for splash-shield removal. | Required | search retailer |
| Jack stands 2 ton pair, pinch-weld pads Support the car at the front jack points before working underneath. | Safety | search retailer |
| Wheel chocks Rubber pair Block the rear wheels while the front is raised. | Safety | search retailer |
| Socket set 10 mm and 12 mm sockets, 3/8 in drive 10 mm removes the engine cover studs, heat shields and under-engine splash shield bolts; 12 mm for bracket/cover bolts on the turbo cars. | Required | search retailer |
| Trim clip / panel tool Plastic pry set Pop the plastic rivets and clips holding the lower splash shield without breaking them. | Recommended | search retailer |
| 3/8 in ratchet and extensions 6 in, 10 in extensions plus wobble extension Reach the sensor down past the manifold heat shield; the wobble lets you get the socket square. | Required | search retailer |
| Oxygen sensor socket 22 mm slotted, 3/8 in drive (7/8 in equivalent) The slot clears the sensor pigtail so you can turn the sensor without cutting the wire. | Required | search retailer |
| Offset oxygen sensor wrench 22 mm crowfoot / offset O2 wrench, 3/8 in drive Backup for the 1.5T where the sensor sits too close to the turbine housing for a straight socket. | Recommended | search retailer |
| Pick / small flat screwdriver Hooked pick Release the red-tab locking clip on the A/F sensor connector and pop the harness clips off their brackets. | Required | search retailer |
| Penetrating oil PB Blaster or equivalent Soak the sensor threads on a high-mileage car; apply on a cold engine and wait. | Consumables | search retailer |
| Wire brush and brake cleaner Brass brush, aerosol cleaner Clean the boss threads and wipe away carbon before fitting the new sensor. | Consumables | search retailer |
| Anti-seize compound Nickel-based, sensor-safe Only if the new sensor comes without pre-coated threads; keep it off the sensor tip. | Consumables | search retailer |
| Torque wrench 3/8 in drive, 10-80 ft-lb Set the sensor to spec so it seals without stripping the manifold threads. | Required | search retailer |
| Air/fuel ratio sensor (upstream, Sensor 1) Denso OE-fit for 1.5T (L15BE), 2.0T (K20C4) or Hybrid (LFA) — order by VIN These are wideband A/F sensors, not plain O2 sensors; the three engines use different part numbers and connectors. | Parts | search retailer |
| Mechanic's gloves Nitrile or heat-resistant The manifold area stays hot and the shields have sharp edges. | Safety | search retailer |
| Safety glasses Carbon and penetrating oil come straight down at your face when working from below. | Safety | search retailer |
| Thread chaser / M18x1.5 sensor tap M18 x 1.5 O2 port tap Only if the old sensor tore threads; cleans the boss instead of forcing the new sensor in. | Recommended | search retailer |
All three engines use a 22 mm sensor and 10 mm cover/heat-shield fasteners, so the tool sizes do not change. What changes is access: the hybrid (LFA 2.0 Atkinson) sensor is reachable from above at the front of the manifold, the 2.0T (K20C4) needs the lower splash shield off and is worked from below, and the 1.5T (L15BE) sensor sits so close to the turbine housing that an offset 22 mm crowfoot wrench is often the only thing that fits. Sensor part numbers and connectors differ between all three, so order by VIN.
| Upstream air/fuel ratio sensor | 33 ft-lb (44 Nm) — verify in the service manual for your engine |
| Exhaust manifold heat shield bolts (10 mm head) | Approx. 9 ft-lb (12 Nm) — verify in the service manual |
| Under-engine splash shield bolts | Snug only, roughly 7 ft-lb (9 Nm) |
| Front wheel lug nuts (if wheel removed) | 80 ft-lb (108 Nm) |
A 22 mm slotted oxygen sensor socket on a 3/8 in drive (7/8 in works in a pinch). You also want a 10 mm socket for the engine cover, heat shields and lower splash shield, plus extensions and ideally an offset 22 mm crowfoot for the 1.5T.
No. There is no registration or coding step - just clear the stored codes with a scan tool and drive the car so the readiness monitors reset, which typically takes one or two mixed-driving cycles.
Usually not. P0420 is a catalyst efficiency code and most often points to the catalytic converter or the downstream sensor. Check fuel trims and both sensors' live data before spending money.
About 33 ft-lb (44 Nm) - verify in the service manual for your engine. Thread it in by hand first and use a torque wrench; over-tightening into a hot aluminum or thin steel boss is how people strip the port.