Smoking Coolant Reservior 5VZ

First off I’d like to introduce myself where I am new to the forums. My name’s Gavin, I’m a proud father and salmon farmer, and was hoping to be a 4Runner enthusiast, but my hopes are not high. I have a 1999 4Runner, with the 3.4 5VZ backed by a 5-Speed manual. I bought the vehicle with 170k, knowing it needed rocker panels, and the power steering fixed. Where those were not too important to me, I drove it for 5,000 miles until my rear differential let go due to a leaking rear cap. While I have been in the process of trying to find the time and funds to fix, it has been sitting for a little over 3 months. I try to start it every week and let it run for a few to keep things moving. I decided tonight I would run a mixture of Seafoam and 93 Octane to clean things out a little. Well after about 15 minutes, I checked the temp and did a walk around, then popped the hood. To my surprise, my coolant reservior is letting out a white smoke. My temp was a little on the upside of middle, but barely. To my info I have never over heated the vehicle, and never had this problem before hand, and have never had a vehicle smoke from the reservior before. I have been told that it could possible be my head gaskets, I just wanted some insight from forum members who know the vehicles better than I do, thank you in advance. If it happens to be the head gasket, I am going to part with the vehicle simply because I do not have the time or funds to fix all of these problems that keep occurring. Thank you in advance.

 

Sounds like it could be.

Get on of those head gasket testers from auto zone with the blue liquid. Some people don't have luck with it but I've had it work before.

 

Dang hope its nothing too serious, let us know what you find though