Skip the auto shop - Our mechanics make house calls

Q: P0302 code & car makes puttering noises

asked by on

The P0302 code is showing. The spark plugs are good - my mechanic checked them. At low speeds, in town, the car literally goes putt-putt-putt. I want to have the IAC valve changed. Do you think that's a good idea?

Hello. The P0302 diagnostic trouble code indicates that a misfire has been detected on cylinder 2. Before changing the IAC valve, it would be a good idea to address the P0302 diagnostic trouble code and have the spark plugs, spark plug wires, ignition coils, or ignition control module inspected. This may solve the problem. If you aren’t getting a diagnostic trouble code for the IAC valve, then it may not need to be replaced. The P0302 trouble code is commonly resolved by having a tune up completed on the vehicle. Keep in mind that there are times when this trouble code is caused by a faulty fuel injector, burned valves, or a dead engine cylinder. I would suggest that you have an inspection of the misfiring condition completed by a certified technician, such as one from YourMechanic.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Loud clicking noise from top of engine and oil leaking after driving

Hi there. The oil leak needs to be found first. If it is leaking a lot of oil or if the oil filter is leaking, then the low oil level will cause these symptoms. Once the oil leak is found...

Q: Rough idling misfire & a thumping sound from the front of engine

Hello. It sounds like your cam timing may still be off or there may be another issue. I would typically do a compression test first. If the compression is low on only a couple of cylinders, then you have an...

Q: Codes showing: P0171, P0420, P0174

Hello. These diagnostic trouble codes are an indication that there could be a problem with the oxygen sensor or that there is a vacuum leak. It is possible that the vacuum leak is located in the intake manifold. These codes...

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.