Same Problem
New to this forum and new to Toyota ownership. I recently purchased privately a 2005 4Runner with 158,000 on it, single owner in the town I live. Everything about it seems great, especially for being a new england vehicle all these years. I even spoke to the local mechanic who has worked on this for the previous owner, and he says she always cared for the vehicle.
After digging deeper into the thing, I noticed an exhaust smell in the coolant overflow. I came on here and in a matter of minutes found all these problems. I plugged in my OBD, and of course I found P0306 pending. Misfire in cylinder 6. I talked to a mechanic on the phone, and he says I need to swap the coil etc to see if the code moves, and don't jump to conclusions. That makes me trust him more, since hes not trying to jump on the opportunity to take the huge job. He said hes willing to do the work if need be, and the estimated price, at least over the phone, was great.
Its not losing coolant or overheating or anything like that, which has me thinking I may have caught the issue relatively early. I thought about letting it ride for a while until I actually threw a code, but also don't want to risk creating further issues. Based on my reading here, it seems like there's no chance I get lucky, and a blown head gasket is clearly the issue.
I can't believe how common this issue is. Has Toyota not addressed this because the vehicles are older now? Yet, they replaced everyone's dashboards?!?
Good luck to everyone going through this, it's not a cheap or quick fix. Thought I would share my experience since it seems to be relatively common...
Lineman8