'87 F150 cold start stalling

[lightorch]

1987 F150 with 5.0 fuel injectioned engine

My truck runs fine after it warms up for a couple minutes. It's when I first start it - it stumbles and dies if I press on the accelerator to much or if I put it in gear and try to move forward or back.

I had a tuneup with, plugs, wires, cap, rotor and fuel filter. I even added some fuel injecton cleaner. But still the samething.

Any Ideas?

Thanks,
Bruce

[NJ Gabe]

bad coolant sensor is my guess

[lightorch]

I thought the computer was in open loop on a cold start. How could the CTS be the problem?

thanks

[NJ Gabe]

it sounds like the engine is not getting enough fuel when it's cold. If you think back to pre-computer and pre-fuel injection cars. If the choke was not closed enough, you had cold driveability problems like sputtering and stalling. Once the engine warmed up a bit, the problems went away. If the choke was closed too much, the car would flood. Maybe the sensor is stuck in closed loop, you would have to test it with a multi meter.