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What P0420 means for your Equinox
Your catalytic converter is no longer cleaning exhaust gases effectively. On the 2010-2017 Equinox with the 2.4L Ecotec (LAF/LEA), excessive oil consumption from worn piston rings is the leading driver of cat failure. GM extended powertrain warranty coverage under special policy and class action settlement (Berman v. GM) addresses this. The ECM detects this by comparing upstream and downstream oxygen sensor readings. You will fail emissions but the car is generally drivable short-term.
Top Causes on the Chevy Equinox 2.4L
62%
#1 CAUSE
Oil Consumption Damaging the Catalytic Converter
The 2.4L Ecotec is documented to burn a quart every 1,500 miles or less due to worn piston rings and an undersized oil control ring. Oil entering the exhaust coats the catalyst substrate, destroying its ability to oxidize hydrocarbons. GM Special Coverage Adjustment 14882 and the Berman v. GM class action settlement cover this. Replacing the cat without fixing the oil consumption guarantees a repeat failure within 20k miles.
Parts
$450-$900
Labor
$200-$350
Total
$650-$1,250
24%
#2 CAUSE
Downstream O2 Sensor Failure
The post-cat oxygen sensor on the Equinox 2.4L runs hot and is prone to slow response after 90k miles. A lazy downstream sensor mimics the upstream signal, fooling the ECM into setting P0420 even when the cat is healthy. Verify with live scan data before condemning the converter.
Parts
$60-$150
Labor
$50-$100
Total
$110-$250
14%
#3 CAUSE
Carbon-Fouled PCV / Intake Causing Rich Run
The PCV orifice in the intake manifold clogs on the Ecotec, causing intermittent rich conditions that overheat the catalyst. A stuck-open PCV also worsens oil consumption. Cleaning the PCV passage and intake is a $40 maintenance item that prolongs cat life.
Parts
$10-$40
Labor
$80-$160
Total
$90-$200
Most Affected Equinox Model Years
| Year | Engine | Trim | Typical Mileage | Notes |
|---|---|---|---|---|
| 2010-2013 | 2.4L LAF | LS, LT, LTZ | 70k-130k | Highest oil-consumption rate; Special Coverage 14882 |
| 2014-2017 | 2.4L LEA | LS, LT, LTZ | 80k-140k | Updated rings but still affected at high mileage |
| 2010-2017 | 3.0L LF1 V6 | LT, LTZ | 100k-160k | Lower rate; timing chain wear can trigger P0420 |
| 2018+ | 1.5L LYX Turbo | L, LS, LT, Premier | 60k-110k | PCV / valve cover issues can foul cat |
Is It Safe to Drive Your Equinox with P0420?
Short answer: Yes for a few weeks, but the oil consumption is the real problem. Driving with low oil on the 2.4L Ecotec accelerates cat damage and risks bearing failure. Check oil weekly. If you are more than a quart low between changes, treat the oil consumption first.
How to Diagnose P0420 on a Chevy Equinox
- Measure oil consumption. Mark your dipstick at a known level, drive 1,000 miles, and recheck. If you are losing more than a quart, you have the documented 2.4L Ecotec consumption issue. Replacing the cat without fixing this is throwing money away.
- Pull TSB / class action coverage. GM Special Coverage 14882 and the Berman v. GM settlement may cover engine repairs (rings, pistons) that lead to cat damage. Bring your VIN to a Chevy dealer or check NHTSA.gov before paying out of pocket.
- Live-data the downstream O2. At 2,500 RPM steady the post-cat O2 should sit near 0.6-0.7V with minimal switching. If it mirrors the upstream rapidly, the cat is spent. If it is flat-lined at 0V or 1V, replace the sensor first at around $120 before buying a $700+ cat.
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Chevy Equinox P0420 FAQ
Is the Chevy Equinox 2.4L cat covered under a recall?
There is no NHTSA recall on the catalytic converter itself, but GM Special Coverage 14882 and the Berman v. GM class action settlement may cover the engine repairs (piston rings) that destroyed the cat. Bring your VIN to a Chevy dealer for current coverage status.
How much does it cost to replace the catalytic converter on a Chevy Equinox?
Expect $650 to $1,250 total for an OEM-spec aftermarket converter and labor. Dealer pricing with GM parts runs $1,400 to $2,000. CARB-compliant converters required in California add roughly $200.
Will replacing only the catalytic converter fix the P0420?
Only temporarily if the underlying oil consumption is not addressed. New cat lifespan on a 2.4L Ecotec burning oil is often under 30,000 miles. Fix the rings or accept the recurring cost.
Can I drive my Equinox with P0420?
Short term, yes. The car will not strand you, but it will fail OBD-II emissions inspection. More importantly, if oil consumption is the cause, continued driving without topping off can lead to bearing damage.
See all P0420 causes and vehicles → · Related Equinox issue: Timing P0011 →