I got a 1990 Mighty Max a few days and have been trying to figure out what is wrong with it.
I will try to explain my problem the best I can but I usually not to good at explaining problems.
In the mornings or if it has been sitting for a while it is kind of hard to get to start. It will turn over several times before it starts. After it starts it will die right away. This usually happens a few times before I am able to keep it running with the throttle. (After it warms up it usually starts up normally) The whole time is it running very rough/missing. I have to keep it running with the throttle for a little while before it will idle on its own. It seems to idle "smoothly" but idles very high (I don't have a tach but I would guess around 1500rpm) When I start to pull out it will buck and jerk around but I can eventually get it up to speed and it drives almost normal but feels down on power and always runs rough and misses. It will also bog down and sometimes sound like it is backfiring in the intake if I try to give it alot of throttle. Sometimes when I am driving like on the highway going a steady speed and holding the gas steady it will suddenly bog down really bad almost like you cut the key off for a second or two then it will start going again. When I come to a stop and try to pull out it will sometimes bog out really bad and wont go at all and will usually die. I have got stuck in traffic like this a few times and couldn't pull out LOL. I have to crank it back up and try to pull out several times before I am able to get it going again.
At first I though it was mainly due to bad plug wires because they were very badly dry rotted and half the boot was broken off of each one. I assumed the spark was arching over to the head. I swapped the plugs and wires for a new set but the problem is still there. I have not been able to replace the cap and rotor yet but I have cleaned them. I also removed and cleaned the EGR, air flow meter, TPS and O2 sensor. I also put a new fuel filter on today. After all this it seemed to run a little bit better for a few minutes and then went right back to doing the same thing. I have a check engine light on too but I cant check it until I get a analog voltmeter. I tried to read it with my digital one but it cant keep up with the changes in voltage enough to try to read it.
Sorry for such a long post. Just trying to give as much info as I can so I can hopefully get this fixed