Getting very bad gas milage.

[ahhjaws]

Any suggestions would be appreciated. It's getting probably around 3-4 instead of the usual 12 or so. The check engine light popped on which give a code that the o2 sensors weren't working. we swapped that out twice with a bosch and they kept getting stuck on full rich, still nothing, replaced spark plugs/wires, still nothing. Check engine light is still on, but I haven't checked if its the same code or a different one.

Now the computer said that both o2 sensors are not working, but the tech I took it to said I only had 1 o2 sensor. Are there 2? Cause we only replaced that one.

 

[Rhett]

Re: your mileage: Did you check the fuel pressure regulator?

Re: O2S. I believe a 92 has 1 O2 sensor. I know for a fact all 91's do, and that 94's have two. Somewhere along the line another was added.

Check that FPR!

 

[MrShorty]

'92 does indeed have only one O2 sensor.
If you've replaced the sensor and are still getting the same code, then I would suspect something other than the O2 sensor is at fault. As suggested, incorrect fuel pressure could cause an O2 sensor code.
Which O2 sensor code are you getting? Rich or lean? What do the spark plugs indicate -- rich or lean?

 

[Brian_B]

I don't know much about computer codes or anything, but my 02 wires got unplugged on my old ranger somehow. Check the connection for corrosion or just being loose maybe?

 

[metstalker]

my 94 dosent have 2

 

[trucku]

Did you reset the computer so engine management can learn new readings....Oh wait does the '92 have similar computer as 2002?. ...

 

[Swee294349]

i know why chris...it couldn't be bc of your HUGE tires could it? J/K...You should only have one O2 sensor on your truck...my truck seems to drink A LOT of gas as well. did you check your truck with a scanner?

 

[Rhett]

my 94 dosent have 2

how many O2s do you have on your 94?

 

[boominXplorer]

buddy of mine had a problem like that on a taurus. PCM went crazy and left injeftors 2 and 3 on 100% of the time Which we found out with the special test bulbs that plug into the harness. It needed a new PCM. I hope its not a problem like that but I'm just trying to give you ideas and diag options

 

[ahhjaws]

i know why chris...it couldn't be bc of your HUGE tires could it? J/K...You should only have one O2 sensor on your truck...my truck seems to drink A LOT of gas as well. did you check your truck with a scanner?

haha, It's just been lately when the light has come on. I was gett suprisingly high mpg with the huge tires. lol

 

[ahhjaws]

I'll be checking the pressure reg next and reset the computer again to see.

 

[metstalker]

how many O2s do you have on your 94?

just one before the cat

 

[Bwana Bob]

A faulty fuel pressure regulator will cause O2 sensor codes.

Bob

 

[rosspueblo]

pull the vacumn hose off the back of fuel regulator. If there is fuel in the line then reg. is bad. Mine just did the same thing and drove me nuts. It will read o2 sensor but is actually dumping extra fuel into rear cylinders to let you know regulator is bad. If you wait to long like I did it will pop that vacumn line off and you will have fuel shooting all over the engine.

 

[wingot]

what about the TPS?