91 4Runner stalls/won't start while city driving
 

For the past few weeks now my 4Runner has had some problems stalling out then not starting for anywhere from 5 min to 3 hours. I've seached this site and found a lot of stuff about cold weather starting, but it starts fine in the cold. It seems that when I'm stop & go driving, and turning it off then on frequently during the day running errands. Sometimes it won't start at all and sometimes I'll be at an intersection and start to go (5spd), then it dies and won't start. My boyfriend will have to push it out of traffic for me. When it does finally start there seems to be tons of black smoke coming from the exhaust for a minute or so. But then it'll run crappy until it sits overnight. Any ideas?? Thanks........lj

V6 or 4 cyl?

If it is fuel injected, then it sounds like a fuel injection problem. It sounds like a sensor is bad and causing it to run way to rich. Heat is probably a factor is causing the bad sensor to malfunction. See if there are any codes in the computer that would point to a bad sensor. Also check for any melted or broken wires that could be shorting. If it is carbureted, then this is a different story.

Greetings!
When a vehicle starts up in the morning she runs a little rich via the injectors staying open a little longer and the cold start time switch, cold start injector..., after the vehicle warms up it shouldn't run rich any more. On yours and most EFI Toyotas you can give it all the gas you want and it won't "flood" the engine, however, once you start to crank the engine the fuel pump kicks on delivering fuel, turning on the fuel pump,injectors...! Since your 4runner is stalling and you go to start it and it doesn't start, every time your cranking that engine it's delivering fuel, whalla - black smoke out the pipes!
When was the last time you had this 4runner tuned up?
I'm going to go with: A. Check your Tps, B. Fuel pressure regulator & C.AFM
If it didn't start after sitting for awhile I'd suggest a fuel pump, but you said that after 5minutes - 5hrs, she starts.
I'd also check your codes like another poster recommended.
So, check your TPS, fuel press. regulator,AFM, Tune-UP and codes!
Good Luck!