vehicle running rough at certain speeds, 'popping' sound...

[hednupnorth]

Since September, my Explorer has been operating funny. Here are the symptoms:
1.) At around 40 mph, and 50 mph, and then 70 mph, my vehicle 'stutters,' 'misses(?),' almost like it's running out of gas, but then after a bit, is fine.
2.) Sometimes, while it stutters it makes a 'pop' sound, and you can 'feel' the pop in the gas pedal (freaks me out!). I kinda' think it's more apt to do it under load (driving up a hill, pulling a trailer up a hill, etc.), but it has done it without being under load, also.
3.) my Engine light (which has been on for awhile..I'm pretty sure it's an Oxygen sensor), will flash for a bit, then stop flashing, but remain on.

I put some injector cleaner in my tank last week, and it seemed to dimish the those symptoms noted above a little, but it seems to have returned to it's intial level this week. I thought it might be a fuel filter issue, fuel injector, spark plugs, maybe..something like that but some feedback from some more experienced guys would be great. Thanks for your time!

 

[rwenzing]

The flashing CEL means that the PCM is detecting significant misfire in real time. A solid CEL means that at least one fault code is stored in the PCM.

Plugs/wires would be a good bet if you have lots of miles on them, same for the fuel filter. Less likely but possible: injectors, EGR or a base engine problem.

 

[bluesman2333]

On carburated cars, the popping is backfire in the intake from running too lean. I assume it's the same on injected engines too. My '97 is running lean too and I think it might be a leaking intake but I haven't had the time to look at it.

 

[hednupnorth]

The flashing CEL means that the PCM is detecting significant misfire in real time. A solid CEL means that at least one fault code is stored in the PCM.

LOL!!! what? Ok..misfiring ok..think I get that.

Plugs/wires would be a good bet if you have lots of miles on them, same for the fuel filter. Less likely but possible: injectors, EGR or a base engine problem.

yep....over 190,000. What do you mean by "a base engine problem"? Something basic, like general maintence related (new plugs, wire, etc?)? It IS in need of a tune up...new plug n' such.

thanks for the feedback.

 

[rwenzing]

What do you mean by "a base engine problem"?.

Like something wrong with the basic mechanical parts of the engine itself as opposed to fuel delivery, ignition or control problems. I don't really believe it's that, just another "possible".