On Monday, my engine started to misfire pretty significantly, running really rough. I drove the truck from VT to NJ (255 miles) without a problem, ran strong at 75-80 mph @ 1600-2500 rpm the whole way through no problem. Next morning I drove it to work (75 miles), once again 75-80 mph and same engine speed without a single hitch. When driving home from work I got stuck in the terrible NJ traffic and did no more than 10 mph for about 1.5 hours, after about 45 minutes of the heavy traffic, the engine developed a heavy misfire, so bad I pulled over. I figure it might be getting hot from sitting in traffic on a 90 degree day so I let it sit for about an hour in the rest area. When I started it back up once again had the misfire, the next morning the misfire was still there on the way to work. But, here is where I am baffled, on my way home I stopped at Sears auto to get some injector cleaner hoping that would solve the problem. I was in Sears for about 30 minutes, when I came back outside the misfire went away before I even put the injector cleaner in it!! I changed out the plugs about 5,000 miles ago when I was having another misfire problem. It still runs a tad bit rough, by no means 100%,but it ran 200% better than it was 30 minutes before and it does also have 285,000 miles on it.
I am just curious as to why the misfire miraculously disappeared, it has actually happened before where it will misfire heavily then all of a sudden disappear again. This leads me to believe that it is electronic and not necessarily mechanical, since usually when something mechanical fails it stays that way. I have had other various little electronic issues, such as the dash not lighting up, gauges not necessarily working all the time, and my right blinker becoming my 4-way flashers every once in a while. Has anybody else had these issues, and can shed some light on whats going on with my electrical system?
The motor does have some mechanical issues, and does need rebuilt heads, would probably fail a smoke test, leaks some oil into the cylinders through the valve seals, but I still don't get why it has the sporadic bouts of running very rough.
Any help would be greatly appreciated.
I am just curious as to why the misfire miraculously disappeared, it has actually happened before where it will misfire heavily then all of a sudden disappear again. This leads me to believe that it is electronic and not necessarily mechanical, since usually when something mechanical fails it stays that way. I have had other various little electronic issues, such as the dash not lighting up, gauges not necessarily working all the time, and my right blinker becoming my 4-way flashers every once in a while. Has anybody else had these issues, and can shed some light on whats going on with my electrical system?
The motor does have some mechanical issues, and does need rebuilt heads, would probably fail a smoke test, leaks some oil into the cylinders through the valve seals, but I still don't get why it has the sporadic bouts of running very rough.
Any help would be greatly appreciated.
