Hello Scotty! Greetings from Katy, Texas....I just bought a 2002 Mitsubishi Montero XLS with 147k for 400 bucks! I scanned the truck and the code p0303 popped up which said that cylinder 3 was misfiring. Also the truck blows out blue smoke from the exhaust when it’s running. What is the issue and how should I go about fixing? Thank you very much sir! And thank you for all of your knowledge
-Renne A.
Assume you cleared the code and it comes back quickly(ish). Plug, wire, injector cylinder #3. I'd start by swapping a couple coil packs around to see if the missfing cylinder changes. Repeat with injector on #3. Of course the obvious plug and plug wire check. Check all wiring very good connecting to coil pack.
If the above doesn't fix/lead you to the issue, check compression #3. How much oil does it use? How well does it run?
I had a 2004 montero limited with the same issue, solved it by changing cable, sparkplug and cleaning the injectors. Sold it with 140000 miles. Those engines are fairly reliable. the only other "major" issue I had was an error in the 4wd indicator: the solenoid needer replacement, I never change it.
