Mitsubishi Repair Problems? Ask a Mechanic for Answers ASAP
Just co confirm, are we talking about code P0301?
OK. First let me clarify that a code can only indicate that a particular circuit is out of parameter, not that a component needs to be replaced.
Bank 1 is the side of the engine closest to the bulkhead/firewall. Cylinder 1 is the one closest to the passenger fender.
P0301 basically means the onboard computer saw the crank speed slow down when it was cylinder 1's turn to push. Now this can happen due to several reasons, most common of which is a lean condition.
How is the idle with the trans in Park?
Ahh... Autozone... the place full of wannabe-mechanics whose main goal is to sell you parts - last I heard, there are some counties/states that have banned auto parts retailer such as Autozone from "diagnosing" vehicles.
Back to our issue, with the engine running at idle, spray choke cleaner on and around the EGR valve. If the engine smooths out, the EGR valve is bad and needs to be replaced. I've attached a couple of graphics showing the EGR location.
Please let me know what you find.
OK. That tells me it's probably not the EGR valve and certainly not an injector problem, which leaves us with ignition as the most probable cause. The next step would be to determine if the problem is with the primary or the secondary circuits. Since the coil was replaced with no effect, I'd say the issue lies with the primary circuit.
Taking all necessary safety precautions, have a helper run the engine at 1500 RPM power-braking it in Drive while you backprobe the #1 coil connector Black/White wire with a LED test light (DO NOT use a regular test light). If the light doesn't flash brightly and rapidly, chances are the connector or the wire to the PCM are faulty; or worse, the old bad ignition coil burned the driver in the PCM.
Can you check and let me know?
Not a problem. You can use a good signal from another coil as reference, just don't backprobe the White/Red wire.
If the EGR was the problem, the misfire would go away when the engine got over 1500 RPM. Let's focus on the primary ignition circuit for now.
Yes, the chat will stay open. I usually login from 2-8PM ET
Looking forward to hearing from you then.