beach_yota

86 4runner 5spd, Ive noticed it really runs horrible when its cold as of recent. sounds like its not runnin on more than 2 or 3 cylinders. As I drive it, It will at some point just go back to normal though and it will be fine for the rest of my driving.

vanduzerwilliam

Check Vaccum lines, tps, maf, temp sending unit

Mine was doing the same, it turned out to be vacum lines, and the. A little tuning of the tps

beach_yota

Well my coolant temp gauge isnt really working. Sometimes it reads right in the middle right when I start it up when it's cold, and other times it wont even get up to the cold mark while im driving

Bassmastry101

iTrader: (1)

Either the connections on the back of your cluster have loosened up or you probably have air in your cooling system. Bleed it out by parking on an incline and running it with the heat on. Top off the coolant as needed.

Kiroshu

Yea Toyotas rely on the temperature of the cooling system for some of the air/fuel ratio.... if theres air then it will be slightly wonky... in matter of speaking.

Faulty coolant temp sensor?

Throttle body coolant passages restircted?

Terrys87

iTrader: (1)

Try raising the front end of your truck and with it running and the radiator cap off let the thermostat cycle several times.

Clean your senors, the one between #2 and #3 injectors and get the 2 sensors in front of the intake manifold. One is the Cold Start Injector Timing Switch and the other is a thermos sensor.


Here is a picture of a dirty Temperture Sensor from my 88 build. I have seen worse. I chipped some of the scale build up off so you could see a difference.


The sensor sits just below the Cold Start Injector in the Intake manifold. Uses a 17mm deepwell socket and is a 5 minute job.

beach_yota

well I have a new development. Looks like I have a blown head gasket now. I was leaving school today and my friend told me I was smoking. I got out, and sure enough I have a nice cloud of white coolant-smelling smoke coming outta my exhaust. When it feels like its only running on 2 cylinders, it smokes, but as it warms up and I feel all cylinders firing again, the smoke goes away and the exhaust goes back to its normal lawnmower smell.

As far as the rough running goes, It runs like crap as soon as I start it up, and as I drive it, I will feel all cylinders trying to fire, and It will stay that way (normal running) as long as Im driving. But if I come to a stop and idle for any length of time, It will go back to crappy running. The longer I idle, the longer it takes for it to run normal again once I start going, and the more I drive, the shorter that smooth-out time gets.

When I got home, my overflow resivoir was pouring steam, so I got a towel and as soon as i turned the rad cap, boiling water and hot steam came flying out

Kiroshu

Ew.. that sucks man time for a top end rebuild ^_^

beach_yota

dude you aint kiddin. only had the truck for 2 weeks too. but everything was just rebuilt 1000 miles ago do you think it needs it again?

vanduzerwilliam

My 3.0 is in the midst of getting a complete rebuild, block, heads, vales everything.. funnsies