2010 is250 - P0303

[jvmagic]

Hi,

My is250 has 110k miles and I've haven't performed a spark plug replacement etc (just basic maintenance throughout the years). The CEL came on yesterday with the P0303 code and the car ran real rough. After reading the code, I reset the computer via my handheld scanner. It's ran fine and no CEL after driving 10-15 minutes. Not sure if I should risk driving further.
Any advice would greatly be appreciated.

Thanks in advance

[dcfish]

https://www.engine-codes.com/p0303.html That's all I have for now...

[Cfauvel]

P0303 means a misfire on cyl 3. I'm new to any Lexus IS250, so you'll have to find a cylinder number diagram to find out which side and what location the #3 cyl is .

The misfire can be a host of things, but a few of the usual suspects are 

Spark Plug (doubt it)

Coil (most probable)

Injector 

 

The easiest thing to do is to clear out the codes and move coil #2 to position #3 (and vice-versa) and see if the PO3xx moves to P0302....If it does that means the coil is bad.
I highly recommend to getting an OEM coil or high-performance coil as some aftermarket coils jus don't cut it.

 

Report back after that test.