P0430 on Chevrolet vehicles
Catalyst Efficiency Below Threshold (Bank 2) — what it means on a Chevrolet, whether it's safe to drive, and the fixes by model and year.
P0430 on a Chevrolet means catalyst efficiency below threshold (bank 2). Most vehicles stay drivable short-term, but diagnose it promptly. The most common cause is worn or contaminated catalytic converter on bank 2 (typically $600–$2,400). Pick your Chevrolet model below for its known failure patterns, recalls, and TSBs.
What does P0430 mean on a Chevrolet?
P0430 is the Bank 2 counterpart of P0420. It is set when the engine control module compares the upstream and downstream oxygen sensor signals on Bank 2 and determines that the catalytic converter for that bank is no longer storing and releasing oxygen efficiently. P0430 only applies to V-engines and inline engines with separate exhaust banks; four-cylinder engines do not set P0430.
P0430 is a standardized OBD-II code, so its definition is the same on every Chevrolet. What differs by model and engine is which cause is most likely — pick your Chevrolet model below for a diagnosis tuned to its known failure patterns, recalls, and TSBs.
Is it safe to drive a Chevrolet with P0430?
In most cases a Chevrolet stays drivable for short trips with P0430 active, but diagnose and repair it promptly. This is a moderate-severity code — ignoring it can lead to further damage or a failed emissions test. Exact tolerance depends on the model and engine.
What causes P0430 on a Chevrolet?
| Cause | Likelihood | Estimated repair (USD) |
|---|---|---|
| Worn or contaminated catalytic converter on Bank 2 | Most common | $600–$2,400 |
| Failing downstream (post-catalyst) O2 sensor on Bank 2 | Common | $150–$450 |
| Exhaust leak upstream of the Bank 2 downstream O2 sensor | Common | $100–$500 |
| Untreated misfire or rich/lean condition on Bank 2 cooking the cat | Occasional | $200–$1,200 |
| Oil or coolant contamination from internal engine wear poisoning the cat | Rare | $1,200–$3,500 |
| Cheap aftermarket catalytic converter that does not meet OEM efficiency | Occasional | $600–$1,800 |
Repair costs are typical US ranges and vary by Chevrolet model, model year, and labor rate. A diagnostic trouble code is a symptom, not a guaranteed failed part — confirm the root cause before replacing anything.
P0430 by Chevrolet model
Select your Chevrolet model and year for a P0430 diagnosis tuned to that vehicle's failure patterns, recalls, and TSBs.
Chevrolet Silverado 1500
1,648 NHTSA owner complaints · 14 recalls on record across the years covered below.
Chevrolet Equinox
1,100 NHTSA owner complaints · 8 recalls on record across the years covered below.
Chevrolet Tahoe
518 NHTSA owner complaints · 11 recalls on record across the years covered below.
Chevrolet Malibu
1,697 NHTSA owner complaints · 8 recalls on record across the years covered below.
Chevrolet Traverse
795 NHTSA owner complaints · 9 recalls on record across the years covered below.
Chevrolet Trax
117 NHTSA owner complaints · 3 recalls on record across the years covered below.
Complaint and recall counts are NHTSA totals for the model years covered on this site, not counts specific to P0430.
P0430 on other makes
Other codes on Chevrolet vehicles
P0430 on a Chevrolet: frequently asked questions
What does diagnostic trouble code P0430 mean on a Chevrolet?
P0430 is the Bank 2 counterpart of P0420. It is set when the engine control module compares the upstream and downstream oxygen sensor signals on Bank 2 and determines that the catalytic converter for that bank is no longer storing and releasing oxygen efficiently. P0430 only applies to V-engines and inline engines with separate exhaust banks; four-cylinder engines do not set P0430. P0430 is a standardized OBD-II code, so the definition is the same on every Chevrolet — which cause is most likely varies by model and engine.
What are the symptoms of P0430 on a Chevrolet?
Check Engine Light is illuminated (steady). Slight loss of fuel economy. Faint sulfur or rotten-egg smell from the exhaust. Vehicle fails OBD-II emissions / smog testing. Rarely any drivability issue at idle or cruise
What causes P0430 on a Chevrolet?
Worn or contaminated catalytic converter on Bank 2 (most-common). Failing downstream (post-catalyst) O2 sensor on Bank 2 (common). Exhaust leak upstream of the Bank 2 downstream O2 sensor (common). Untreated misfire or rich/lean condition on Bank 2 cooking the cat (occasional). Oil or coolant contamination from internal engine wear poisoning the cat (rare). Cheap aftermarket catalytic converter that does not meet OEM efficiency (occasional)
Is it safe to drive a Chevrolet with P0430?
In most cases a Chevrolet stays drivable for short trips with P0430 active, but it should be diagnosed and repaired promptly — this is a moderate-severity code. Ignoring it can lead to further damage or a failed emissions test. Exact tolerance depends on the model and engine.