Welcome Visitor! Please take a few seconds and 
86ranger4x4owner
New Member
- Joined
- Jun 2, 2010
- Messages
- 538
- Reaction score
- 0
- Points
- 0
- Vehicle Year
- 1988
- Make / Model
- Ford
- Engine Size
- 2.9l
- Transmission
- Automatic
The injector cleaner didn't work. The spark knock is still there. It comes and goes. It does overheat a little at times so maybe that could be causing it? I did replace the thermostat about a year ago with cheap 192 degree one. I'm thinking it could be the problem and causing it to overheat causing the spark knock. As for the misfire I'm not sure if it is a misfire it just idles a little rough right about 1000 rpms. But the rpms stay steady and don't move so I don't think it's a misfire. Wouldn't you notice a misfire with the rpms not being steady?
