87 chevy help

[autobodyman2]

My buddy has an 87 chevy 350 with an automatic transmission. It was running like crap, so they gave it a tuneup but that did not help. He took it to his mechanic, who said it was out of time. Got it in time, and now it will run great in the garage, but once driven on the street out of park, it does not run worth beans. I have been thinking of purchasing this truck and i know it is something simple. What would cause this?

[Eyegore]

A little more info.
Is the truck carborated or tbi? If tbi- bad fuel pump, clogged filter, clogged injection system.
Also what does the altenator read, is it putting out enough current to run the electronic spark under load?
These are simple things that a mechanic should have caught, did he test drive it before returning it?

[hotrodhomi]

no advance?

[autobodyman2]

The truck is a tbi. mechanic said that he can not figure out what is wrong. I believe he put a new sending unit into the truck. anything else this could be?

[87 STEPPER]

The first thing i have to ask is did the mec. disconnect the EST bypass before he set the base timing??

If not theres the problem!!

Theres a small single tan wire with a black stripe around the back of the dist.
and it has a small sorta round connector that has to be disconnected and then the timing can be checked if it's not @ 0*BTC then it needs to be readjusted after thats done turn off the ign. reconnect the EST bypass and see where the timing is it should be way past the pointer and fluctuating thats the computer making the necessary and constant adjustments.

If it dosent advance like i just mentioned then most likely its a bad ign module.

[autobodyman2]

I forgot all about that wire. I bet that he did not disconnect that. Im going try to buy it tomorrow