2021 Ford Bronco · symptom sheet
Engine failure, knocking or rod bearing
- 34owner reports
- 6,000median miles
- 1involved a crash
Newest report Jul 20, 2026 · checked Oct 2, 2026
74 of the 229 complaints on this car are about the engine. 34 of those describe engine failure. Only stalling is reported more often on this car.
Tick what matches of 34 reports
Engine failure on other Bronco years
No other Bronco model year has enough reports of engine failure for a sheet of its own. See every Bronco year.
What this problem usually is
These are the reports nobody wants to file. The engine started knocking or ticking, the oil light came on, and then it seized or had to be replaced. Some owners had the replacement covered under warranty or an extension, and plenty were told they'd pay. Several narrower sheets split this group into knocking, seized engines and rod bearing failure.
What got replaced
Owners who name the part that was replaced mention the engine (34 reports).
Recalls and investigations
3 recalls on the engine cover the 2021 model year. A recall on the same system isn't always the same failure, so read the defect text.
The engine compartment wiring harness may become damaged and short circuit.
The engine block heater may crack and develop a coolant leak, causing it to short circuit when the block heater is plugged in.
The engine intake valves may break while driving, which can result in engine failure and a loss of drive power.
All 20 recalls on the 2021 Ford Bronco, with the owner complaints on each recalled system
NHTSA investigations into the engine on the Bronco
Loss of motive power. Closed oct 31, 2024, led to recall 24V-635.
Loss of motive power due to valve intake failure on ford bronco vehicles.. Closed oct 2, 2023.
Loss of motive power. Closed jul 28, 2022.
Idle air spd ctrl vlv malf. Closed aug 31, 1994.
Idle air spd ctrl vlv malf. Closed jul 30, 1993.
When it happens
The middle half of failures fell between 2,322 and 6,976 miles, from the 11 reports that gave a mileage.
Is this a known problem?
The manufacturer has sent NHTSA 1 service bulletin or notice for the 2021 Ford Bronco 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.
Some 2021-2023 Ford and Lincoln vehicles equipped with a 2.7L or 3.0L engine may exhibit an upper engine thump/knock noise coming from the left cylinder head. This condition is most noticeable at idle and may lessen at higher engine speed or while driving.
What owners wrote
“2.7 engine failure while accelerating on to a hwy. Loss of acceleration and power. I was unable to get fully off the road. Engine was replaced under warranty only 3,636 miles on car. No warning lights prior to this failure. Once engine failed and started smoking the check engine light came on.”
Filed Mar 24, 2024 · 3,636 miles
“Driving on the highway, the check engine light came on. I felt a loss of power in the vehicle, and couldn't accelerate. I was able to pull over put the car in park and turn it off. When I tried to turn it on, there was no power. Had to get it towed to the dealership to replace the engine.”
Filed Jun 14, 2023
“On May 17th At 6,800 miles my motor randomly experienced catastrophic engine failure and has been at the Ford dealership since. The dealership has not told me anything on how or why this happened other than the motor needs to be replaced. The dealer received the new motor on June 22nd.”
Filed Jul 20, 2022 · 6,800 miles
“Engine completely destroyed with no notice at 4600 miles destroyed itself in less than three minutes while driving. New engine replaced”
Filed Jun 12, 2022 · 4,600 miles
Should you keep driving it?
This page can't tell you that. 1 of 34 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 Paid for this repair before a recall covered it? How recall reimbursement works
Other problems on this car
- Engine stalls or loses power while driving 43 reports