Going Crazy!!

[Rganther]

93 explorer eddie bauer

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Here is my issue. Rough idle strong exhaust smell ,light black smoke, At times when trying to accelerate above 35 like there is nothing there,push the pedal and nothing let off pedal and power resumes, awfull sputtering coming from exhaust. Than sometimes you will hear this pop and it will idle and run fine,exhaust clears, than pop and back to same old crap.Replaced oxygen sensor today 65 bucks,not the problem,cleaned MAFS, not the problem, unplugged MAFS, idle went to normal, nasty exhaust dissapeared plugged in while running back to crappy, Went up and bought MAFS, 99 bucks, not the problem HELPPPPPP!!!!).Check engine light is not coming on. ECT sensor? oh yeah,when you first start and accelerate the temp gauge will climb all the way to the far right and than back to normal right away and remain at normal.

Thanks for any help,

 

[Masterd]

If its black smoke, its running rich....check the FPR and the injectors...one or two might be stuck.

 

[doonze]

Like I said in the other thread you posted this in, if you unplug the MAF and it runs right, and you've replaced the MAF (keeping in mind that it being new doesn't mean it's any good), then it's another sensor that's your problem.

Umplugging the MAF puts the PCM into a "fail safe" mode, it uses best guesses on the safe side of things. (and it may use SOME sensors, but I don't know anyone who can tell me what ones) It will default to slightly rich pre determinded settings instead of trying to adjust in "real time". Just rich enough to keep things safe for the engine, but not rich enough to cause issues unless there is a physical problem with the engine. (Prefomance, MPG, and pollution suffer in this "fail safe" state, that's why it's only a back up)

So, you have something sending the PCM a bad siginal, or a bad PCM. That's what unplugging the MAF and everything running ok tells me.

If it ran worse, or the same, I would have a different opinion.

 

[shaggymane]

Harbor freight recently had a fuel pressure tester for $10. Wish I'd thought about HFR8 when I bought one. O' Reilly's got 40 bucks outta me for an FP tester.
I went through the same thing. No CEL but i learned how to pull codes. I knew the MAF was good but couldn't figure out how to get hold of the wires on the O2 sensor. So I gambled on the O2 and lost.
While your at HFR8, you might consider picking up a DVOM. Cheap ones there are $4 on sale. AZ gets 20 for about the same thing. You don't have to buy the dirt cheap one either.
Then you might learn how to test the parts you pulled out. If they do test good then put em back in and sell the *new* ones on craigs list for, I dunno, 75% of what you paid?
Something to consider.

 

[Rganther]

Re

How would one go about seeing if one of the injectors are stuck? FP Tester?
One more sill question how would one get an injector unstuck besides the obvious remove/replace injector?
Thanks again for any help guys,

 

[deamon3]

I had a similar problem with an s15 I had , all I had to do was change the spark plugs.

 

[Masterd]

Testing the fuel pressure with a gauge would be a dead giveaway for FPR.

As for cleaning injectors I'd say either some fuel injector cleaner, or worst case having a shop sonically clean them.