Howdy. I have a 94 ACTY HA4 I picked up last August from Mayberry. About a month ago, I romped on the throttle to get up to speed in traffic and immediately noticed some issues with the truck. If I started giving it more gas, I would feel it bog down. I thought it was a throttle cable issue or something but couldn’t find anything. Still drove it occasionally but the issue continued to get worse. It really started running rich and bogging down with less and less throttle to the point that I can’t drive it. Anything more than idle it immediately bogs down and has no power. I thought the butterfly valve wasn’t opening all the way but hopped on here and saw a number of people had issues with the air solenoids, so I was going to pursue that. Because it was running rich, I went to check my plugs and found some oil on the plugs and in the plug bores. I know a little bit when it comes to working on engines but not enough to know what that could mean. I’m also getting some moisture covered in a black film coming out of the tail pipe (it doesn’t smell like gas). Some assistance and guidance would be awesome. I’ll probably attach a YouTube video on this thread of what I’m seeing.
My first thought is maybe when you goosed the throttle it ruptured the accelerator pump/power valve diaphragm causing it to suck in excess fuel from that point on? I could be off base as I’ve never worked or even looked at an acty. The oil in spark plug wells is likely just the gaskets on valve cover allowing some seepage.
Oil on the outside of the plugs is just the valve cover gasket. Easy fix. Rich running . . . I'm having sort of the same issue. Lot's of very sooty black deposits. Stumped as well. Mine starts easy, but won't stay running without blipping the throttle when cold. Takes several minutes to warm up, all while blipping the throttle or it stutters, starts running on two cylinders and then dies. You blip the throttle and get it firing on all three it runs fine for a few seconds and then slowly goes back to stuttering, runs on two and the process repeats until it warms up a bit or you just get in and drive it. It's gotta be a carb/too much fuel issue. I'm just not sure where to start.
check the 2 solenoid valves I mentioned here https://minitrucktalk.com/threads/honda-acty-losing-power.20677/#post-118719
Mine was doing many of the same things + gas in the oil. Ended up being the carburetor air vent solinoid. Heads=up when testing the solinoid, they can be intermittent defecto.
