Recent Feedback
2003 sonata has a check engine light on, when you turn it off wont start until it cools down, and has stalled three times in a week but starts back up once it cools down. Had a p0421 code.
Country: United StatesMake: HyundaiModel: Sonata GLYear: 2003Engine: 2.4L Already Tried: Before getting the code, replaced starter and battery. o2 sensors appear to be new.
Hi welcome to JA.com.I will answer your question the best I can,Please do a good test drive for 10 mins then check for codes again. Regards Greg
Same code
Hi .
A code P0421 may mean that one or more of the following has happened:
Experience: 27 year and 16 year as shop owner, import technician
How do I check to see if there is a spark to my plugs?
You will have to pull out a coil from the cylinder head and connect a known good spark plug, then ground the spark plug on the top of the head valve cover and crank the engine over and see if the plug is sparking?Greg