2020 Chevrolet Blazer · symptom sheet
Check engine light or misfire
- 35owner reports
- 60,000median miles
- $1,400median quote
- 0involved a crash
Newest report Sep 14, 2026 · checked Oct 2, 2026
131 of the 219 complaints on this car are about the engine. 35 of those describe misfire.
Tick what matches of 35 reports
Misfire on other Blazer years
No other Blazer model year has enough reports of misfire for a sheet of its own. See every Blazer year.
What this problem usually is
These reports start with the check engine light. Many describe the engine running rough or shaking at idle, a P0300-series code, or a catalytic converter code. A worrying number say the light was flashing. Owners often list ignition coils or spark plugs already replaced, and the light coming back afterward.
What got replaced
Owners who name the part that was replaced mention the sensor (14 reports).
Recalls and investigations
No recall on the engine covers the 2020 model year as of Oct 2, 2026.
NHTSA investigations into the engine on the Blazer
Engine compartment fires. Closed jul 31, 1996.
Fire in dash/instrum.clstr. Closed sep 14, 1994.
Elect. failures/fires. Closed jul 16, 1987.
None of these investigations covers the 2020 model year.
What owners paid
6 of the 35 reports quote a price. Each dot is one quote. The middle half runs $1,000 to $1,400.
When it happens
The middle half of failures fell between 50,000 and 70,000 miles, from the 13 reports that gave a mileage.
Is this a known problem?
The manufacturer has sent NHTSA 17 service bulletins or notices for the 2020 Chevrolet Blazer that deal with this problem. Newest first.
Federal rules make a manufacturer send NHTSA a copy of any notice about a defect that goes to more than one dealer or owner. Most of these are service bulletins, the repair instructions manufacturers send to dealers. NHTSA generally leaves safety recall bulletins out of this file, and recalls are listed separately.
This Preliminary information communicates the potential for condensation to freeze up inside the Crankcase Pressure Sensor causing dtc P04FB to set.
This service bulletin provides inspection/diagnosis/correction information on a cold start misfire and/or rough idle and DTC P0300 that may also be set.
This service bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or misfire, MIL with DTCs, and explains how Top Tier fuels should be used to reduce ...
This technical bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or misfire, MIL with DTCs, and explains how Top Tier fuels should be used to ...
13 more on the 2020 Chevrolet Blazer page.
What owners wrote
“Engine temp gauge bottoms out because the thermostat is stuck open, causing the air to stop working. Also a warning that the steering assist is reduced. Eng check light comes on with a code P0208. This a known problem with an extended service # (N242484760) but only if your vin is listed. All vehicles with this problem should be covered”
Filed Jun 5, 2026
“P0128 code for thermostat issue. Fans run after shutting car off. Steering assist reduced message. Check engine light. Chevy knows this is a common issue. This needs to be investigated asap.”
Filed Mar 10, 2026
“There seems to be a constant problem with the service driver assist error code popping up and check engine light coming on. The ac heating keeps losing temperature. I've looked for support for this issue and it seems to be a common problem for chevy owners. Why isn't there a recall on this.”
Filed Dec 23, 2025
“Engine light on, power steering assist, air conditioning stop working diagnostic tool read p0128 coolant thermostat”
Filed Oct 8, 2025
Should you keep driving it?
This page can't tell you that. 0 of 35 reports involved a crash. Owners who file are the ones who had a bad experience, and nobody checks their reports. If the problem affects steering, braking, power or a fire risk, treat it as a safety fault and have it inspected before a long or high-speed drive.
File your own report with NHTSA. Complaint counts are how a problem gets an investigation. How reports land on this sheet.
Guide Which lights mean pull over now? Warning lights by color and urgency
Other problems on this car
- Engine overheats or leaks coolant 48 reports
- A/C blows warm or the compressor fails 43 reports
- Power steering cuts out or goes heavy 35 reports
- "Shift to Park" or "Service Shifter" warning comes on 30 reports
- Infotainment, screen or backup camera fails 29 reports