P0300 on a 2017 Jeep Compass
P0300 is a generic OBD2 powertrain code for random or multiple cylinder misfire. Unlike P0301 through P0308, it does not point to one specific cylinder, so the cause can be ignition, fuel, air, sensor, or mechanical.
Not your vehicle? See general P0300 info.
Most common causes on the 2017 Jeep Compass
Ranked from 228 NHTSA owner complaints filed for this vehicle.
- 1
Excessive oil consumption (2.4L Tigershark) fouling spark plugs / low oil pressure
High severityMultiple owners report the engine burning a quart of oil every few hundred miles, low-oil-pressure warnings, and stalling; oil-fouled plugs and marginal oil pressure are a documented misfire/stall pattern on this engine family.
Reported in 6 NHTSA complaints - 2
Camshaft/crankshaft position sensor fault (post-recall)
High severityThis Jeep was built right after a recall covering the camshaft and crankshaft position sensors; the owner has a recurring bank-1 cam sensor code and stalling that persisted even after replacing the sensor, a corrupted cam/crank signal being a classic P0300 trigger.
Reported in 2 NHTSA complaints - 3
Faulty electronic throttle body
Medium severityOwners had the throttle body replaced for stalling/power-loss complaints that recurred; an erratic throttle body disrupts commanded airflow enough to produce a rough-running or misfire-like condition.
Reported in 2 NHTSA complaintsParts:throttle body - 4
Worn or oil-fouled spark plugs
Medium severityOne owner replaced all spark plugs and the O2 sensor chasing a check-engine code with continued jerking/power loss; plug fouling is aggravated by this engine's known oil consumption.
Reported in 1 NHTSA complaintParts:spark plug - 5
Vacuum or intake leak
Medium severityUnmetered air entering downstream of the MAF leans a cylinder enough to misfire at idle.
Common cause - 6
Clogged or leaking fuel injector
Medium severityA dirty or leaking injector under- or over-fuels a cylinder, producing a misfire.
Common causeParts:fuel injector - 7
Carbon-fouled intake valves
Low severityBuildup on the valve stems/seats disrupts sealing and airflow to one or more cylinders on higher-mileage engines.
Common cause
Part links go to Amazon search results for this vehicle. As an Amazon Associate, WrenchConnect earns from qualifying purchases — always confirm fitment for your exact trim and engine before ordering.
These causes are aggregated from NHTSA owner complaints and general repair knowledge — this is not a diagnosis. P0300 on your car still needs shop confirmation before any repair.
Common symptoms
- Flashing or steady check engine light
- Rough idle
- Shaking under acceleration
- Loss of power
- Fuel smell from exhaust
What to check before replacing parts
Scan for cylinder-specific misfire codes
Look for: A companion P0301–P0308 pins the misfire to one cylinder — start there. P0300 with no cylinder code points at something hitting several at once: fuel pressure, a large vacuum leak, or timing.
Inspect the spark plugs and coils
Look for: Pull the plugs: black/sooty = rich, oily = oil intrusion, white/blistered = lean or overheating, cracked porcelain or an out-of-spec gap = replace. Then swap a coil to another cylinder — if a cylinder-specific code follows the coil, the coil is bad.
Check fuel trims for a vacuum leak
Look for: High positive short- and long-term trims (worst at idle, improving as RPM rises) mean unmetered air is getting in. Smoke-test the intake and listen for hissing.
Verify fuel pressure
Look for: Compare running/cranking pressure to the vehicle spec. Low or dropping pressure starves multiple cylinders and reads as a random misfire — suspect the pump, filter, or regulator.
Compression / leak-down test if ignition and fuel check out
Look for: A cylinder 15%+ below the others, or leak-down hissing from the intake (intake valve), exhaust (exhaust valve), or oil filler (rings), means the misfire is mechanical — not a swap-in part.
Rather have a pro handle it? Find a vetted local mechanic.