Need Help Diagnosing P0301, P0303, P1300
#21
10-23-2017, 03:46 PM
Since you've been digging up old threads I had to find yours to maybe lend a hand. I'm no mechanic but I chased a misfire for quite a while.
The sludge coming into the intake is from the PCV system. On the passenger side valve cover there is a hose to the intake manifold. Inside the metal outlet on the cover is an oil separator. That is supposed to help keep the oil residue from entering into the intake. While chasing mine I replaced my oil separator and cleaned the valve covers thoroughly.
Also, per the RAVE the ignition coils operate on a wasted spark system. The coils fire in pairs so that it fires in one cylinder during the ignition sequence, and also fires at the same time the other cylinder in the exhaust stroke. In other words if you actually have a bad coil it would be affecting two cylinders at the same time. They are paired:
1 & 6
8 & 5
4 & 7
3 & 2
Now that isn't to say you couldn't have a bad lead on a coil only affecting one of them, but it's just something to keep in mind.
I chased my misfire for ages. I replaced just about everything, coils, wires, plugs, fuel injectors, front 02 sensors. I still couldn't shake it. For me, it turned out to be mechanical and didn't clear up until I removed the valve covers, removed the rockers assemblies and thoroughly cleaned them. That may not be the case for you, just my experience.
The sludge coming into the intake is from the PCV system. On the passenger side valve cover there is a hose to the intake manifold. Inside the metal outlet on the cover is an oil separator. That is supposed to help keep the oil residue from entering into the intake. While chasing mine I replaced my oil separator and cleaned the valve covers thoroughly.
Also, per the RAVE the ignition coils operate on a wasted spark system. The coils fire in pairs so that it fires in one cylinder during the ignition sequence, and also fires at the same time the other cylinder in the exhaust stroke. In other words if you actually have a bad coil it would be affecting two cylinders at the same time. They are paired:
1 & 6
8 & 5
4 & 7
3 & 2
Now that isn't to say you couldn't have a bad lead on a coil only affecting one of them, but it's just something to keep in mind.
I chased my misfire for ages. I replaced just about everything, coils, wires, plugs, fuel injectors, front 02 sensors. I still couldn't shake it. For me, it turned out to be mechanical and didn't clear up until I removed the valve covers, removed the rockers assemblies and thoroughly cleaned them. That may not be the case for you, just my experience.
Appreciate you digging into my comments/threads - I've had some luck with bumping old threads and there are so many times where the same issue has been posted, I thought I'd be a considerate poster and start with the old first.
I had been hearing a more noticeable "ticking" sound which I chocked up to being a slight exhaust leak but since I'm digging into the motor, I'll be removing the valve covers and checking the rocker assemblies. This amount of work is new for me so I'll be taking it slow.
As for that sludge, would you recommend I clean it out with carb cleaner and a rag or just wait and do a engine flush/seafoam treatment when everything is back together? I did pick up the oil separator too to replace.
I'm replacing plugs, coils, wires, gaskets, and front O2 sensors for good measure.
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