What is wrong if a 1991 Chevy Lumina that drives fine and then stalls and won't crank back up until you let it cool down but it's not overheating and it blows black smoke out of the tailpipe?

Answer 1

Answeryour fuel injection might be plugged up try putting fuil injection cleaner in gas tank ( run it in 2 tanks of gas )and check your spark plugs Answerif it won't start back up until it cools down, it's probably the crack sensor that sits in the back of the motor, it may be cracked and once it heats up the contact separates causing the car not to start back up until it cools down, and goes back together, and makes contact, I've had that problem also, and once I changed the crack sensor, it worked. I went to the junk yard and found one, just so I would bye one and that not be the problem Answeron that last answer I meant the Crank sensor not the crack sensor AnswerThe black smoke coming out of the tailpipe means you have a rich air/fuel ratio. the motor is taking in too much fuel. As for the stalling and wont start til it cools down, this can be caused by a faulty ignition module. It is located behind the coil packs, which are under the front exhaust manifold. its the sensor in the back of the engine but sorta on top. its on the rear manifold. silver in color. i just had to change mine 93 model you might also want to check your EGR valve and catalytic converter

All of the Answers above are related to the problems you are having. However, You must be going around the problem see below:

You must be methodical in your logic to the problem. The engine function is a round house effect setup (What comes first and what part or parts are not feeding the ECM computer). The computer sends the signals to fire and open and close the injectors and the only check is the O2 sensor to see if gases are to lien or to Rich. It dose not check Fire or if the fuel burned or have fire at the Plus.

1. The engine is dying after it gets heat, varies with outside air temp.
2. Black Smoke from tail pipe.
3. Will start after engine cools, varies with outside air temp.

Let's start with number two (2).

Black Smoke is a sign of to much gas to air mix.

Cause:

1. Fuel Pressure to High (Pump or Regulator or both {use a Fuel Gauge (40LB)}. See Manual for lb.

2. Fuel Injector sticks open when hot (Check all Spark Plus, note the one that is Black or Glazed).

3. Check for O2 Computer codes (IT will read for RICH Mix)

Now One (1).

The engine is dieing after it gets heat.

Cause:

1. Fuel Injector shorted out, limiting the current to the other injectors so they don't have the power to open, so the engine dies.

2. Black Smoke on restart or during operation, see 2 above.

3. Use a Hall Effect Timing Light to check all S.P. Wires for fire at this time. If you have Spark at the Wires you are back to Fuel and Injectors.

And Three (3).

Will start after engine cools.

Cause:

1. Fuel Pressure drips to normal or below.

2. Injector cools and releases or short goes away. You can get to two of the injector connectors, one on each bank of three, two banks, to check the current or voltage to the banks. Use a Load test Light on the connectors you can get to. If the light is brown you have a short in one of the two injectors in that bank.

Both Light types and fuel pressure gauge can be rented from the auto store. Use your logic on the fuel injector testing.