I have a 95 4.0 Sport with 202,000 miles.
Recently, it has a little stumble at idle. It doesn't feel like it's going to die or anything...just a little rough, and you can see the engine move. You can also here a little "poof" sound at the tailpipe about once per second or so, and smell a little richness in the exhaust.
I replaced the cap, rotor, and wires. I inspected and gapped the plugs (Bosch platinum with 15k on them- they look fine). The cap and rotor were DONE.
I take it back in and idle emissions of HC went from 360 to 325 (180= passing). At 2400 rpm, it passes like a champ. This leads me to believe maybe it's a clogged fuel injector, and once it's opened up and spraying the tiny bit of clogging isn't much of a problem, but at idle it isn't always spraying a uniform mixture and doesn't always ignite. I put a bottle and a half of techron in the tank, but I'm not sure what else to do. Any ideas?
Recently, it has a little stumble at idle. It doesn't feel like it's going to die or anything...just a little rough, and you can see the engine move. You can also here a little "poof" sound at the tailpipe about once per second or so, and smell a little richness in the exhaust.
I replaced the cap, rotor, and wires. I inspected and gapped the plugs (Bosch platinum with 15k on them- they look fine). The cap and rotor were DONE.
I take it back in and idle emissions of HC went from 360 to 325 (180= passing). At 2400 rpm, it passes like a champ. This leads me to believe maybe it's a clogged fuel injector, and once it's opened up and spraying the tiny bit of clogging isn't much of a problem, but at idle it isn't always spraying a uniform mixture and doesn't always ignite. I put a bottle and a half of techron in the tank, but I'm not sure what else to do. Any ideas?