wabtfin

My pickup seems to be only firing on three cylinders. I removed the plug wires one at a time while the engine was running. When I got to Number 3 cylinder, there was no noticeable change. I had replaced the head and assumed that when the shop put in the valves, etc. that they were adjusted to factory specs.(my mistake). After adjusting the valves, the truck ran great for a while with much more power than before. But a few days later, it was back to sounding like it was just firing on 3 cylinders.

I have replaced the air flow meter, thermo sensor, and re-adjusted the throttle position sensor all because of Check Engine Codes. I also replaced the spark plugs, distributor cap, and rotor button. I have re-checked the timing and have checked compression in each cylinder. I didn’t record exact compression readings on each cylinder, but they were all at 180 psi or above as best I could tell.

Could my problem be a sticky valve? Or, is there something else obvious that I am not seeing?

olharleyman

Sounds like it could be a sticky valve

dark_fairytales

also could check the electrical connection to the injector they are old and im sure are cracked. I have found mine have fallen off a few times. hope it is that simple

wabtfin

Thanks to both of you. I'm new to this forum stuff, but it is easy to see this is a group of good folks willing to help a novice wrench turner. I'm not sure how to fix a sticky valve. Can you clean them with mineral spirits or add some kind of oil treatment that will help? Also, I read in another post about unplugging the connector to the injector to see if it made a difference in how the engine ran. Would this help to narrow things down if it was a bad connector to the injector?

olharleyman

Good call yea it could be not completely connected or a grounding out from a crack in one of the wires.

wabtfin

Olharleyman & Dark Fairytales, you guys are great. Yes, I know it's 2:05AM in Reform, Alabama. But I went outside and checked the injector connectors on the Yota and one was a little loose. I secured it and went for a test drive. Unbelievable how much better she runs with fuel going to all 4 cylinders! I got her up to about 80 mph, which I think is a record for her even before the blown head. If either of you ever come through Reform, Alabama, the drinks are on me! I'll even throw in a bass fishing or deer hunting trip if you are so inclined. Thanks!!!

Bulldog

ya i had just had the same problem with my 86 22RE but it wasnt fireing on cylinders 1 and 3 after changing the head and timing chain. what i found was that one of the electrical wires going into each of these plugs had came out when i connected the plug to the injectors. once i found the and fixed the wire the motor ran great with no misses.

dark_fairytales

ill keep that in mind but im just glad it all worked out. We all need help some time.