Explorer Check engine light on with a ton of symptoms

[SteveCxlt]

I have been searching the web for why my explorer is running like crap. Personally I think I got a lemon as before my warranty ran out it was in the shop 6 times in a year. Now my warranty is up my check engine light came on and it has been running crappy. I will get the codes pulled this weekend but am curious to see some ideas on what is wrong. Below I have listed all the symptoms. Thansk for your help.

Loss of gas milage
RPM's fluctuate when stopped (almost stalls)
boggin on acceleration
smelly exhaust
darker then normal smoke from exhaust
sometimes a smell of gas
loud humming when air vents are turned on past the 3 setting
boggins seems worse when going from a stop and accelerating uphill

I cleaned the MAF and it does seem to run a bit better I have read about cleaning the TPS aswell and I also just read about an issue that may involve the cat. I reset the computer but my check engine light came back on. I think I may have more then one issue here. It is a 1998 Ford Explorer XLT 4.0 SOHC 82,000 miles

 

[SteveCxlt]

I just read a whole huge article about cleaning the IAC that may be my idle issue but none of the others really go with this. As for the humming noise it's only when I turn on the air vents. I never hear it any other time.

 

[Turdle]

Have the code pulled-
Autozone will read them free of charge-then try to sell you an o2 sensor-
this may well be the problem, but please don't buy any parts until you post the problem code(s) here. We'll help you troubleshoot this-

Any suggestions at this point would be shooting blindfolded

 

[SteveCxlt]

Will do! Hopefully I can get up there before this weekend.

 

[SteveCxlt]

Just another little update. I pulled the IAC and cleaned it out. It was full of what looked to be carbon residue. I thought the little shaft looking thing was supposed to be lack untill I noticed a speck of silver. So I grabbed a q-tip and some cleaner and started going to work. The thing is spotless now. Just waiting for it to dry to put it back on. I will keep you up to date.

 

[Cobraguy]

sounds like it's running rich. You could pull the plugs and see if they are black.

 

[SteveCxlt]

Still haven't gotten the codes pulled. My son has been sick so it's tough to get out of the house and get it done. Another thing I noticed it liquid coming from the exchaust. It is an odorless liquid. I will get the codes pulled asap and check my plugs. After cleaning the IAC and MAF it does seem to run better but still am having a check engine light on.

 

[BobWiersema]

Ok this may sound crazy but it did happen to my 98 xlt 4.0 sohc.
Just a shot in the dark here, get the codes pulled.
I had all the same problems for about a week, then noticed oil on the ground under the right front, it was dripping from the air cleaner. Strange right? Came to discover that the PCV had slipped out of the larger hose on the bottom, that was the noise I heard, the lack of power and the rough idle was from the vacuum leak and the check engine light, that was caused by the vacuum leak causing a lean condition that looked like a bad o2 sensor. So I plugged the PCV valve back into the hose and put a small clamp on it and it's been fine since.

Just something to check.

Bob