Hello, this may be a couple problems, I am not sure. I'll just take you through the symptoms in the order they started appearing. The vehicle is a 1991 Toyota Pickup, EFI, 4 cylinder, 5 speed manual. Thanks, and here we go!
1. It started idling especially high several month ago, when this started I could gun the gas a little (while in neutral) and the engine would calm down. Eventually this quick fix stopped working and.
2. Especially when the engine is cold, when not moving, in neutral or in a gear with the clutch pushed down the engine "surges", ranging from around 1k RPM and 2.5k RPM.
3. The heat started intermittently working
4. When cold, occasionally it wont turn over immediately, but if I was about 1 - 2 minutes after trying to start it, it starts.
5. It's now starting to overhead, riding the line between safe and warning on the gauge, and on occasion will shoot steam out of the radiator/coolant reservoir overflow (a small hose connects the reservoir and radiator, then a small piece of tubing continues past the reservoir, that's the overflow thats shooting steam.