While driving the MIL chimed , check engine light is active along with low battery gauge illumination and low battery warning light , in park vehicle idling is erratic in drive or reverse idle is erratic also with spurts of motion, no active or stored codes are present but MIL is active
2021 RAM 1500 engine problems
moderate 99 complaints filed with NHTSA · avg repair $3,100 · see engine across all vehicles →
Failure mileage
Complaints
99
Recalls
0
Avg fix
$3,100
1fire
What stands out
Owners have filed 99 engine complaints with NHTSA against this vehicle, but no formal recall covers the issue — the federal record reflects what manufacturers have admitted, not everything owners are reporting.
No new NHTSA engine complaint has been filed on this vehicle in over 4 years — the issue may be aging out of the active population.
The failure pattern owners describe
Buyer takeaway: 2021 Ram 1500s face recurring engine stalls during low-speed turns and starts—sometimes without warning codes—alongside widespread exhaust manifold cracking that vents exhaust into the cabin. Dealers often cannot reproduce these issues despite acknowledging they are documented problems, and parts shortages mean multi-month wait times for repairs.
The 2021 Ram 1500 shows a pattern of intermittent but serious engine issues. Most common is unexpected stalling during low-speed turns or acceleration from stops, occurring as early as 1,200 miles. Engine simply shuts off with no warning lights or codes—parking brake engages automatically, transmission shifts to park, and the driver must restart manually. Owners report this happening dozens of times across various mileages. Dealers consistently claim they cannot reproduce the problem despite owners documenting it on video and multiple mechanics confirming the same failure mode.
Exhaust manifolds on both left and right sides crack prematurely, allowing carbon monoxide into the cabin through the heater and defrost. Independent shops confirm the defect and report long waiting lists because the failure is widespread. Owners cite bolts described as inadequate by mechanics.
Additional engine failures include sudden shutdown at highway speeds with no restart difficulty, high-pressure fuel pump failure with metal shavings in fuel lines, and limp-mode activation triggered by warning lights and severe power loss. One vehicle caught fire without warning after parking.
Engine internal damage (failed lifters, cracked cylinder walls) has required complete engine replacement on vehicles under five years old. Motor generator unit failures strand owners with eight-month parts lead times. Oil pans rust through prematurely, risking catastrophic engine seizure. Dealers refuse warranty coverage on most issues and often cannot diagnose root causes despite service bulletins suggesting known problems.
Same RAM 1500 engine reports on nearby years: 2018 · 2019 · 2020
Failure modes owners describe
Exhaust Manifold Cracking
Both left and right exhaust manifolds develop cracks, allowing carbon monoxide to enter the cabin and escape into the atmosphere before reaching the catalytic converter. Owners report minor exhaust leak noise that progresses to significant cracking over time. Metal thickness approximately 1/8 inch, held by 12 bolts. One independent shop reported a long waiting list due to high defect rate. One owner noted bolts inside the manifold were deemed inadequate.
When: Varies; one owner at 59,700 miles; another reported issue starting as minor leak and progressing over time
Symptoms owners cite: Carbon monoxide fumes entering cabin via heater/defrost; Exhaust leak odor; Ticking sound from engine
Repairs/costs cited: Independent shop estimated 2-4 weeks for part availability due to high defect rate. One owner had right side replaced; left side refusal by Dodge. One dealer quote over $1,500 for oil pan replacement (separate but related corrosion issue).
Recalls/TSBs owners mention: Dodge refused to replace left side manifold for free despite verification from authorized dealer and independent shop.
Engine Stalling During Low-Speed Turns and Acceleration
Engine shuts off without warning while making turns (left or right) at low speeds (2-25 mph) or during slow acceleration from stops. Occurs intermittently, most frequently in first few thousand miles. No diagnostic codes or warning lights precede the stall. Vehicle automatically engages parking brake and shifts to park. Driver must restart engine manually. Multiple owners report dealers unable to reproduce despite documented issue.
When: First occurrence as early as 1,200 miles; continues sporadically through 56,000 miles. Most incidents reported within first 15,000 miles.
Symptoms owners cite: Engine shuts off without warning during slow turns or acceleration; Automatic parking brake engagement; Automatic transmission shift to park; No warning lights or codes before stall; Smooth stall (no sputtering); Immediate restartability
Codes mentioned: P1C64 (Hybrid Perf. Engine Speed Below Target During Autostart), PO627 (fuel pump circuit code)
Repairs/costs cited: Multiple dealer visits yield no codes or reproducible issue. One dealer acknowledged documented issue with no known repair available. One owner had PCM software updated; another had ECU flashed from old to current part number without resolution.
Recalls/TSBs owners mention: Dealers unable to replicate; case numbers opened (e.g., Case #82559049) but no resolution offered. Service bulletins for earlier builds referenced but deemed non-applicable to later build dates.
High-Pressure Fuel Pump (HPFP) Failure
Engine shuts down suddenly while driving, preventing restart. Starter spins but engine does not fire. Metal shavings found in fuel lines and injectors. One owner reported symptoms similar to prior Ram HPFP recalls. Requires towing and replacement of fuel pump and related fuel system components.
When: Approximately 33,000 miles; one reported around 60,000 miles (MGU failure may be separate)
Symptoms owners cite: Sudden engine shutdown while driving; Starter spins but no fire; No warning prior to failure; Vehicle stranded in roadway
Repairs/costs cited: Metal shavings in fuel lines and injectors required replacement of multiple parts. Wait time for parts estimated at time of complaint.
Recalls/TSBs owners mention: Service writer identified failure as HPFP; parts ordered. Owner noted similarity to prior recall for earlier Ram models.
Electronic Throttle Control / Limp Mode Activation
Warning lights (check engine, electronic throttle control) appear with vehicle entering limp mode and severe power loss. Occurs during highway driving or at idle. One owner experienced incident immediately after dealer completed exhaust fluid software recall, suggesting potential trigger. Another owner reported warning 'Service Electronic Stability Control' followed by limp mode on steep grades. Vehicle slows dramatically, creating safety hazard. Dealer diagnostics unable to locate root cause.
When: One instance around 70 mph on highway; another on steep grades with trailer load. Timeframe April 2022 for one owner.
Symptoms owners cite: Check engine light illumination; Electronic throttle warning lights; Electronic stability control warning; Sudden severe power loss; Vehicle enters limp mode; Difficult to maintain highway speed; No prior warning codes in some cases
Repairs/costs cited: One dealer installed software update (Cole Chrysler) with no warranty coverage provided; owner charged for repair. Another dealer unable to locate root cause after extended diagnostics.
Recalls/TSBs owners mention: Chronological proximity to exhaust fluid software recall suggests possible connection. One dealer offered software update but charged owner. Another dealer remained unable to resolve despite diagnostic efforts.
Motor Generator Unit (MGU) Failure
MGU fails abruptly in vehicle under 60,000 miles, producing loud noise and stranding owner. Battery warning light and auto start/stop malfunction light appear; vehicle becomes inoperable. Replacement part has extremely long lead time (up to 8 months estimated). Vehicle loses trade-in value significantly due to known issue.
When: Under 60,000 miles; owner stranded 4 hours from home
Symptoms owners cite: Abrupt loud noise from engine area; Battery warning light; Auto start/stop malfunction light; Engine dies completely; Vehicle unable to start
Repairs/costs cited: Dealer advised 8-month lead time for replacement part. Owner paid $7,677.58 for engine replacement on a different vehicle (narrative #11). Another owner reported MGU part 'can't be found no where in the country.'
Recalls/TSBs owners mention: No warranty coverage mentioned. Dealer unable to expedite parts. Trade-in value reduced by $10,000 due to known issue.
Random Engine Stall at Highway Speeds
Engine shuts off without warning during highway driving (45-70 mph). Vehicle restarts immediately or after brief delay. Some incidents report difficulty restarting, requiring multiple start attempts. No diagnostic codes present before or after stall. Owner noted possible fuel pump issue or computer malfunction.
When: Various mileages: 33,000 miles (3 occurrences), 58,000 miles (recurring), 45-50 mph on interstate
Symptoms owners cite: Sudden engine shutdown at highway speeds; No warning lights or messages; Immediate restartability (most cases); No check engine light; All electrical systems remain functional
Repairs/costs cited: One owner at 153 miles found fuel pump circuit code PO627; dealer cleaned ground connection. Another owner reported same issue recurring after dealer service.
Recalls/TSBs owners mention: One owner noted recall on vehicle; hoped repair would address issue. Dealer unable to locate root cause in another case.
Oil Pan Premature Corrosion
Oil pan develops severe corrosion and rust-through, leading to oil seepage. Occurs even with relatively low mileage and short ownership. Common problem reported across northern regions. Repair cost exceeds $1,500. Risk of catastrophic engine damage if pan fails completely.
When: 39,000 miles at time of discovery; approximately 5 years old vehicle; issue appears common in northern climates
Symptoms owners cite: Visible rust and corrosion on oil pan; Oil seeping from pan; Rust-through perforation
Repairs/costs cited: Repair quote over $1,500 for replacement. Not covered under warranty. Owner notes competing vehicles do not exhibit same issue, suggesting inferior material selection.
Recalls/TSBs owners mention: Not covered under warranty. Ram declined to acknowledge systemic issue. FCA informed of complaint but no response documented.
Engine Misfire and Internal Damage
Check engine light illuminates with multiple cylinder misfire condition. One vehicle required engine inspection revealing multiple camshaft lobes flattened and ground due to failed lifter. Another revealed small crack in cylinder wall allowing coolant to bleed into system. Both required complete engine replacement at owner expense.
When: 4 years old vehicle (2021 model replaced 5/2025); timing varies
Symptoms owners cite: Check engine light illumination; Multiple cylinder misfire; Engine performance degradation
Repairs/costs cited: Engine replacement cost $7,677.58 for rebuilt engine on 2021 model. Two separate mechanics consulted with bore scope and internal inspection. Defects included flattened camshaft lobes and cylinder wall crack.
Recalls/TSBs owners mention: Owners unaware of recalls. Dealership cleared recalls on new engine after installation. Issue should not occur on 4-year-old vehicle.
Vehicle Fire
Vehicle caught fire 15 minutes after parking with no warning signs. Family evacuated safely but vehicle destroyed. Initial inspection by Dodge found no obvious cause.
When: After 15 minutes of parking
Symptoms owners cite: Vehicle ignition and combustion; No warning lights or prior symptoms
Repairs/costs cited: Complete loss; vehicle burned to ashes.
Recalls/TSBs owners mention: Dodge performed initial inspection but found nothing; no further follow-up documented.
Synthesized from 99 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 3 most recent
Car has turned off on multiple occasions while driving and emergency brake engages. Very dangerous. Forums show this is a common issue but does not produce an error code. Something must be done.
Vehicle stalls when I hit quickly hit the gas pedal halfway down while turning
Had engine trouble with your 2021 RAM 1500?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2021 RAM 1500?
It's a documented issue but not catastrophic. 99 complaints have been filed. Repairs average $3,100 and most owners catch it before it causes a breakdown.
At what mileage does the engine typically fail?
Across the 11 complaints that reported odometer mileage, most engine failures cluster between 1,915 and 46,000 miles, with the median around 15,319. A quarter of owners report trouble before 1,915; a quarter make it past 46,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2021/RAM/1500.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.