2009 4 cyl. P0301 misfire code and leaky valve cover gasket

Hey all, my 2009 4 cyl. 5 speed manual began starting really rough, coughing and then leveling out to idle. Threw the P0301 code. I changed the plugs. CEL came back. Changed the coil on cylinder #1. Came back. Plug is definitely soiled. I noticed I am low on radiator fluid and that there appears to be some leaking from the left (low) side of the valve cover gasket. Is a failure of the valve cover gasket a possible cause for the P0301 code?
Thanks

 

Check your coolant bypass pipe no.1 on the driver side of the motor below the intake manifold. The original ones were made out of plastic and are known to leak. Also check your water pump and around the t-stat and make sure theyre not leaking. If none are leaking, then it’s likely you have a head gasket that’s starting to go. my 2009 had the plastic bypass pipe, so that’s where I’d start
https://www.tacomaworld.com/threads/water-bypass-pipe-no-1.201053/

 

Thank you. There is no evident leakage from the coolant system. I am wondering if there is any chance the leak from the valve cover gasket/interior plug is the cause of the code P0301 and the fouled plug in cylinder #1 and not the head gasket. Or if these terms are interchangeable, but Rock Auto has both items listed for the 4 cylinder.
The picture below is the "wet" side of the valve cover seal with the "wet" hose showing dry/wet as well. I think it is oil, but a friend thought it had the sheen of antifreeze.

 

I have heard of the spark plug tube seals causing misfires if they’re really bad and leaking oil on the plugs and coils. However, that doesn’t explain the coolant disappearing. A coolant pressure test might be a good start to see if it leaks coolant into cylinder 1 overnight.

 

Thanks Again BassAckwards. To catch you up. I took it to a shop and they replaced the valve cover gasket, serpentine belt, and battery. The second two items may/my not be related to the misfire code. Took the truck back and the CEL come on before I made it home, ~20 miles. Changed the plug in cylinder #1 again thinking it was fouled and that was triggering the CEL.

Next morning, it barely started and the CEL was blinking at me. I turned it off and sat wondering what to do. Restarted it, and voila, no CEL and purring like always. I drove to work and checked the engine when I arrived and saw bubbles in the coolant overflow again.

That evening I put in one can of K seal head gasket repair additives and the bubbles seemed to stop, but returned the next morning. No choice but to drive it. That was four days and over 200 miles ago and it is running great. Starts right up and cruises at 75-80 with no issues. I haven't checked for bubbles again but will keep my eyes on it.
In the mean time I have followed through on my year old idea to buy a second car to allow me to stop daily driving the Taco. So I have some time to find a proper mechanic and see about getting the Taco back to reliable shape.

 

Make sure if you continue to drive it, that you check the coolant level in the radiator regularly after it cools down. If it’s a head gasket like mine was, it might cause the rad to run low and overflow the reservoir but it won’t suck anything back into the radiator out of the reservoir. I had to manually top off my radiator to make sure it had plenty of coolant. Just something to keep in mind so you don’t end up overheating

 

Since you have already used K Seal I would just run the truck and check the coolant level on a regular basis. After having been out for a drive maybe bore scope the #1 cylinder and see if you can see any bubbles.

Also, as mentioned above, if you have the plastic coolant bypass type get it changed out. I did this recently for my 2009. The pipe was not leaking but it was brittle and broke apart as I was removing it. The replacement pipe is made of steel.