P0133: O2 Sensor Circuit Slow Response Bank 1 Sensor 1
A generic powertrain (engine and transmission) trouble code, same meaning on every brand.
Yes - the cost is fuel economy and an emissions test failure.
Symptoms
- Check engine light
- Slightly worse economy
- Marginal hesitation
Likely causes, most common first
- Upstream O2 sensor aged and slow
- Exhaust leak near the sensor
- Contamination from oil or coolant burning
Read P0133 yourself before paying for diagnosis
A basic Bluetooth OBD-II scanner ($20-40) plugs into the port under the dashboard and shows this code with live sensor data on your phone - useful both for confirming the fix and for talking to a shop from an informed position.
What is going on and how it gets diagnosed
P0133 means the front oxygen sensor still works but responds too slowly - the computer times how fast the sensor switches between rich and lean, and an aged sensor fails the stopwatch test. Slow feedback means sloppier fueling.
Sensors slow down with age like tires wear; past 100k miles this code is usually honest aging. If the engine burns oil or coolant, mention it to the shop - contamination kills the new sensor just as fast.
Repair options and cost
Typical US independent-shop ranges, parts and labor. Dealers run higher; regional labor rates vary.
Owner reports mentioning P0133
“While driving dash starts blonking and several issues appeared. Stearing, traction control light, service key, ABS, and others that I can't remember however showing 7 different codes p0133, u0101 u1110 u1120 I don't remember all of it. Reset computer and drive about 200 miles and same not sure what is wrong.”2013 Dodge Charger · Oct 2020 · 160 mi
“Leaking exhaust failure of the resonator increased exhaust noise. Replaced the spark plugs found codes: p0133 and p0301 slow response from 02 sensor and misfire in cylinder 1 and bad check valve. *jb”2000 Saturn SL · Apr 2003 · 53,000 mi
“Repeated cold engine hesitation to the point of stalling when gaining speed from a stop. Manufacturer repeatedly stated that there is no fix and the problem was a "condition of operation"characteristic of all 2001 and 2002 engines, that owner would have to warm the engine prior to use and burn a higher grade of gasoline. Engine light on at time of first service with code p0133. Replaced a/f sensor did not fix problem. Condition was not disclosed to me at the time of purchase. Dealer warms engine prior to customer test drive. After being refused a refund, I traded in the car 11/14/01 at oconner vw, augusta me. Informing owner of dealership about problem.”2001 Subaru Legacy · Oct 2001
Cars that report P0133 most often
Based on mentions of this code in NHTSA owner complaints.
Frequently asked questions
Can I drive with P0133?
Yes - the cost is fuel economy and an emissions test failure.
How much does it cost to fix P0133?
Typical US repair costs range from $100 for the simplest fix (upstream o2 sensor) to $450 in the worst case. The right number depends on which cause your car has - see the causes list.
Definition per SAE J2012 standard nomenclature. Symptoms, causes and costs are editorial guidance - always confirm with a diagnosis of your specific vehicle.