98 Explorer from hell

[Lil Raptor]

Hi all,
Really need help with my 98 sport. Replaced B1S2 and B2S1 o2 sensors. Still bogging out. Im thinking wiring harness damage, bad ground, all plugs good, fuses good. Grrr...yes i reset everything and drove for about 20 miles. Seriously ticking me off. Thinking also PCV or vac leak? Anyone have a chilton or haynes manual I could download? I could really use it...
Sara

 

[1998Exp]

Hi all,
Really need help with my 98 sport. Replaced B1S2 and B2S1 o2 sensors. Still bogging out. Im thinking wiring harness damage, bad ground, all plugs good, fuses good. Grrr...yes i reset everything and drove for about 20 miles. Seriously ticking me off. Thinking also PCV or vac leak? Anyone have a chilton or haynes manual I could download? I could really use it...
Sara

Welcome! Unfortunately, you didn't tell enough to even attempt to help.
What are the symptoms? What prompted you to replace those two sensors? Is CEL (check engine light) on? Did you have the codes pulled? If so what are they? Any previous repairs? Anything else you tried besides replacing these sensors? Mileage?
As for these manuals, they are copyrighted, so you probably can't download them for free. And besides, they are too generic to help you diagnose the problem. Someone here may be able to point you to a much better technical manual, but don't expect any manual to magically tell you what's wrong - it's a process.

 

[Lil Raptor]

P0141 P0155 i believe. I tried taking off neg terminal and after letting it sit I read codes again. Its killing me...new tranny.

 

[Lil Raptor]

12 total codes actually

 

[koda2000]

Hi all,
Really need help with my 98 sport. Replaced B1S2 and B2S1 o2 sensors. Still bogging out. Im thinking wiring harness damage, bad ground, all plugs good, fuses good. Grrr...yes i reset everything and drove for about 20 miles. Seriously ticking me off. Thinking also PCV or vac leak? Anyone have a chilton or haynes manual I could download? I could really use it...
Sara

Does your check engine light work? Is it ON?

A few areas that come to mind:
1) Have you tried cleaning the MAF sensor with the appropriate cleaner.
2) You should check your fuel pressure at the injector rail. IDK if the '98 has the return or return-less fuel system. Return type should show around 35 PSI and the return-less style system around 65 PSI.
3) Examine/test your DPFE sensor. They can melt and leak.
4) Check your EGR valve to make sure it will still hold a vacuum.
5) Check your PCV hoses/elbows and replace your valve if it's been a while.
6) When's the last time you replaced the fuel filter?

 

[Mbrooks420]

List the codes.

 

[Lil Raptor]

Give me a few. I'll get them now.

 

[J_C]

12 is a lot of codes! Check the under-hood wire harness connectors:
2nd gen issues? Try this first!

'98 was the last year to have the return fuel system which should be around 35 PSI. If nothing else indicates a fault then you probably have a vac leak and could use a scan tool to show live data and look at the fuel trims.

If you're getting misfires and its dumping fuel into the cat then that could be failing too... best not to run it any more than necessary till the problem is resolved.