Skip the auto shop - Our mechanics make house calls

Q: Check Engine Light keeps appearing, trouble code changed

asked by on

The first time check engine light went on the code was 302 and 304 we changed all the spark plugs and 1 of the coils. The second time the CEL came on it said 302 so we switched the spark plug and coil to position 1 to see if somehow it was faulty. Now the check engine light is on again and throw code 300 only. So i am guess that it is something else....should i pay for dianostic at this point or should i try something else?

My car has 140000 miles.
My car has an automatic transmission.

A: Hi there, thanks for writing in. Having a p...

Hi there, thanks for writing in. Having a professional mechanic complete a diagnostic inspection to determine why a mechanical part failure continues to happen is always the best course of action; especially if you're frequently replacing spark plugs on a 2010 Prius Hybrid. To avoid any unnecessary repairs, I would highly suggest contacting one of our local mechanics and ask them to complete a Check Engine Light inspection. This will allow them to pinpoint the source of the issues you're having; before spending more money on replacement parts.

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・Save up to 30%

Get a quote

What others are asking

Q: What is P0335 Crankshaft Position Sensor A Circuit and where is it located?

Hello - this message (P0335) indicates that the crankshaft position sensor is failing, causing the "cutting off" you have already noticed. It is located on the bottom of the engine/transmission interface (drivers side of the vehicle). To avoid any unnecessary...

Q: Code P0171. Do I need to take car to dealership to address this problem.

Hey there. It sounds like your throttle body is bad. Check to make sure it's clean and not sticking. Clean the throttle body if necessary and check for loose connections with the throttle body connectors, too. Since you said that...

Q: Service Engine soon light began flashing on and off on 2010 Nissan Sentra... Car started sputtering, ... now all dash lights are o

Hi there - the security system is now active, but this sounds more like the car battery has died (sputtering, then dead engine). Have the car battery checked, possible something electrical left on overnight, or battery is just old? Try...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
How to Renew Your Car Registration in Oklahoma(DELETED)
Having your car registered with the Oklahoma Tax Commission is an important part of driving legally in this state. You will need to do this within 30 days of moving to Oklahoma...