It seems like it is not running on all cyl on 1997 Toyota T100

I can smell coolant burning and it is running rough. Truck has 108,000 miles, auto trany, 4X4, SR5
Check eng light is on, Codes P0300, P0301, P0305 and P0420

Can anyone help me?

Thanks JT

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2 answers 2 comments
Is there white smoke comming from exhust if so probly head gasket
No
You probably have a blown head gasket. The codes you have are for misfires.
Thanks. That is what I though but I pulled two plugs from the side that I see some leaking, but they looked fine.
I guest I should pull all the plugs and see what they look like.
Regarding the misfires codes, should all the coils or just one?

Thanks again for your help
JT