Paulos
Active Member
- Joined
- May 7, 2018
- Messages
- 479
- Reaction score
- 210
- Points
- 43
- Location
- North Carolina
- Vehicle Year
- 1987 STX
- Make / Model
- Ranger
- Engine Type
- 2.9 V6
- Transmission
- Manual
- 2WD / 4WD
- 4WD
A clogged injector will cause that cylinder to run lean while the others don't. The ECM adds more fuel because the O2 sensor is detecting the lean cylinder, which explains the smoke from the bad cat gasket (unless that has been replaced). The O2 sensor doesn't kick in until after the engine has warmed up, which is why it runs better (or did) when it's cold. Mine ran better when it was cold and when the ECM had been freshly cleared. I even installed a battery kill switch so I could reset the ECM by just turning the switch. Then I finally replaced the injectors, as I mentioned in post #2. Problem solved. But even so-called "rebuilt" injectors can have problems, as I had problems with the injectors I got on eBay. I got fed up and bought new Accel injectors with a 30% discount at Advance Auto and that solved the problem. If buying rebuilt injectors, get them from a reputable shop. Use caution when buying them on eBay.