andyrizzla

So I recently just purchased an 07 GS350 from a used dealers. It only had 99,280 mi when purchased. I've only driven it for about 150 mi since purchasing and my check engine light came on. I work at a Valvoline so it's pretty easy for me to have access to the tools I need. When I plugged in the scanner to pull up the codes, it throwing a P0303 Cylinder 3 Misfire. I've read multiple threads on these forums to try and figure out what to do to fix the issue. I've replaced all 6 of my spark plugs (used Denso plugs) and I've switched the coils on cylinder #1 and #3. I drove it another 100 miles or so and the same thing happened. Same code popping up. I've tried fuel additive and intake cleaner to clear any carbon build up that I've read these 3.5l engines are notorious for. But still getting the same code back. If anyone can give me any feedback as to what to try next or if anyone has experienced the same problem please all feedback is welcome. Thank you!

SILENTM

My need to get a borescope down into the cylinder and check for any scoring on the cylinder wall

ibidu1

iTrader: (1)

On cylinder #3 unplug the electrical from the coil pack and inspect the terminals and the seal. If the seal is not seated correctly and you wash your engine you may have moisture on the electrical plug. So I would unplug all the plugs and let them air out just incase