1986 305 distributor problem

[cincy86]

So I bought this truck and drive it home fine. It ran like it needed at tuneup, but it drove. I have since done a full tuneup, and now there's a problem. The truck idles good and can rev throughout the range while in park and neutral, but if I give it any gas while it's in gear, it stalls. I also found today that the 4 prong connector leading to the distributor was unplugged, and if I plug that in, the truck won't even start. Any ideas anyone?

 

[1987 GMC Jimmy]

So I bought this truck and drive it home fine. It ran like it needed at tuneup, but it drove. I have since done a full tuneup, and now there's a problem. The truck idles good and can rev throughout the range while in park and neutral, but if I give it any gas while it's in gear, it stalls. I also found today that the 4 prong connector leading to the distributor was unplugged, and if I plug that in, the truck won't even start. Any ideas anyone?

Was this a California truck? I'll assume no. It's got an Electronic Spark Control distributor, which isn't a computer, but it uses a knock sensor and a controller. Check to see if the knock sensor is there, and if it's plugged in. It's on the underside of the engine block where a block heater or freeze plug would be. Also see if there are any wires associated with that distributor connector spliced or burnt/chewed/cut. It's probably running poorly because the stuff that alters the timing isn't plugged up so it can't modify it. Check your base timing at idle with the four wire harness unplugged, too. If you can make it work, great. If not, you can always pull that stuff out and install a regular old vacuum advance distributor.