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Does this sparkplug look bad to you? Was from engine cylinder 5 misfire..

@lucifargundam The electrode is eroded somehow or started a carbon bridge, the spark gap was massive and you might have some type of oil leak around the plug. The valve cover gaskets might be shot.

The plug looks like it has seen a misfire or two. Check that spark gap and start using anti seize and dielectric grease on the connections. It's not necessary but it's so worth it. If that really is mud on the threads, get all the connectors with dielectric grease. It keeps water out and ensures a good connection.

@AmpBenzScientist
It has antiseize on it beforehand. The misfire has been historically random(it's changed cylinders each time I take the upper intake off, moved plugs n boots n whatnot).

I already replaced the plug seen with a new plug earlier this week. So far no misfires, but only time will tell. I've been reading the codes using a cheap OBD I got from Walmart.

@lucifargundam That's puzzling. Could be low fuel pressure on the fuel rail causing the intermittent misfire. It could be a clogged filter. It could be a number of things but I don't see anything that makes sense.

A compression test will tell if it's the head.

Is it a stumble misfire or a knock misfire?

@lucifargundam It's what it looked like but I'm used to extensive carbon deposits with knocking misfires.

I'd get a cheap cigar and blow smoke around the intake manifold to see leaks if they are present. It looks like a lean misfire so the timing advance could be too much or it's not getting enough fuel at that time. If it's the later, it will usually retard timing and dump excessive fuel to stop it.

I'd look into the fuel system for a filter or a dying pump. The temperature range on the plugs could be an issue too.

Do you have a distributor or Coil Packs? If you have a distributor, that could definitely cause a misfire on different cylinders. The same with something in the fuel system.

I've never had a misfire like you are having. I've had an iron block V8 so hot that it was knocking on every cylinder and my foot was pinning the accelerator. I also had a RAV4 with a Toyota problem.

Neither of their plugs were damaged like your spark plug.

I'd say try a higher octane fuel and check out your operating temperature. That kind of misfire is rough on an engine. That's what compressing an explosion at the wrong time looks like. I don't know why it's so infrequent unless it's a fuel problem. The equipment to test it could be rented from a parts store.

@lucifargundam It could be a bad injector causing the misfire. A scan tool could help you work out the cause. Log live data on ignition, fuel pressure and temperature.
OBD-2 works in closed loop mode until the operating temperature is reached at which point it goes to open loop. Closed loop mode is basically safe mode.

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