Black Smoke from Intake Manifold

Waterbury

True Classic
So recently I had been having issues with warm starts. Cold starts were fine, only slight bogging until it eventually leveled out. If I went to start it back up it would takes a good couple minutes before it was drivable again. There was also slight loss of power upon acceleration, especially after shifting up.

That being said, I have replaced the following very recently; Fuel pump, fuel filter, fuel lines, ignition coil, alternator, waterpump, and cleaned out the MAF. Visually the timing belt looked ok, but I have not checked the timing itself (something I have never done, but I do have the write-up saved from here).

The problem: Went to start the car the other day and it really didn't want to go. Eventually got it to turn over and it idled very rough. Got out of the car to inspect and saw black smoke coming out of the air filter (not a lot, but definitely enough to notice). Shut off the car and removed the snorkel and sure enough more smoke. It didn't smell like antifreeze (checked coolant level and it was still full),wiring, or gas, but more of an actually burning smell. Yet again my nose isn't always the best. There was also a puff of smoke from the exhaust when it started (had that issue since day 1 if I didn't run the car semi-daily), but it did not continue to pour out any more than that. After checking over some things I tried to start it again (yes I know, possibly very bad) and it will not turn over without me really giving it gas, and the black smoke persists.

Am I right to believe this could be a fuel rail issue? Maybe bad injectors? Before I had these warm start issues it was running like a dream.

'86 Fuel Injected
 
I see that you replaced and or checked all of the fuel delivery suspects. Did you replace the air filter ? Usually black smoke indicates to much fuel and not enough oxygen. There could be several things causing this problem and I'm sure there will be others with more ideas.
 
Need to check fuel pressure regulator (rest presssure & running, vac connected and disconnected), cold start valve & thermal timer, aux air slide & hoses, and crankcase breather hose where it attaches to intake hose, and intake hose.

Sounds like it's running way too rich, which could be pressure related, regular or cold start injector related, or an air leak, or AFM flap sticking, or internal (circuit) issue. Could be spark plugs also. Even valve adjustment if that hasn't been checked & mileage is high enough. Basic cam timing should definitely be confirmed.

Need to go through the fault tracing, IMO, if nothing is blatantly obvious. Were the fuel/ign. items listed changed due to known component failure, or to try & fix the current condition?

Pics of engine bay help to assess overall state of things.
 
SOLVED!

Ended up being the spark plugs! Some pics of the old ones. Put the new ones in, adjusted throttle a bit, and she's ready to go! Thanks again guys.
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Got a little spooked by the smoke and was jumping to larger conclusions.
 
Did you replace the cap & rotor also ? With plugs that worn I'd wonder about the state of the other components.
 
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