I have a 93 truck with a 350 TBI. When I start it, it runs really rich, black smoke, misses, I can't touch the gas without it dying. Once the truck warms up everything is fine. Does the TB have some kind of a choke deal on cold starts that could be sticking? Any help would be greatly appreciated.

 

my freind is having the exact same problem and we haven't been able to figure out what it is.... we have replaced the map sensor, egr, plugs, plug wires, o2 sensors, and the whole throttle body, we are thinking it might be the ecu itself or the module in the distributor...it has got us stumped but im sure its something simple...it does the exact same thing you have to let it clean out when you first start but once it clears out it is perfectly fine, if you find out the problem i would really like to know because we have no idea what it is and we are sick of throwing parts at it...also on another note i have seen tons of tbi vehicles do this but still im unsure of the problem... there is no choke on the tbi vehicles either

 

tempature sending unit

 

Thanks for the input, I'll work on it this weekend. rc if I find anything new or something that works I'll keep you posted.

 

could be just pulling stuff out my butt, but could there be an issue with exhaust leak where the leak is so small that once the metal gets warm it doesnt leak anymore but before that the o2 sensor is reading the leak and dumping more gas in. just a thought?

 

Pulled it apart and the injectors are pumping out alot of gas, its misting all over the throttle plate. What would cause it to do this? Something in the cold start circuit?

 

coolent sensor for cold start (PCM)

temp sensor for gauge

Has the TBI base gasket been replaced?
dirty injector will not fan spray,but dribble