1986 2m4 Where to start to look for an intermittent missing causing black smoke. I bought the car last fall and the ride home it was really bad for about 20 minutes out of a 2 hour ride then left her andit ran smooth after that. It came back again at a couple of odd times but left her hen I pulled over and raced it over a few times. I am after replacing plugs,gas and air filter the winter. You are probably going to tell me that I need the tank flushed. I am thinking it's dirt.
Would a sensor cause this problem? Driving to work today going up the same hill as yesterday, the car started to smoke black and miss. I pushed in on the clutch and gave it a few shots of gas and then I went on best kind.
Will check the wiring when I get home. Seems pretty coincidental that it happened when going up the same hill. Could it be dirt/water moving in the tank and getting sucked up? Anyone got the specs on testing of the sensor?
I will check that this weekend and I know the PCV is fine. But by me giving a couple of good shots of gas when its startS to miss it works fine after that, almost seems like its cleaning out some kind of dirt. Would water in the gas also cause that trouble? If so what is the best to get water out of the tank?
The black smoke indicates excess fuel. That would happen if the spark did not fire for a few revolutions and then suddenly fired again. I doubt if water is your problem, but you can purchase an additive for the fuel tank that should take care of it. BTW, if your distributor looks half as bad as Bloozberry's picture, find another one.
Just checked the sensor and the lock for the harness was broke. I bent the sensor leads a little and push the connector in and test drove it and it seemed fine. So I pushed the connector hard in and put tape around it. Maybe the cable was not making a good connection all the time and that is why it was it intermittent and when I revved it over it seemed to help. Is this wishful thinking....lol Raining too much to fully check
[This message has been edited by newfiejeff (edited 04-25-2014).]
Update Must have been a slack sensor connector. I took the car for some gas and a good run it ran perfect and it idles the best it ever did. Would the cts affect the idling? Thanks again for all who helped!!!!