What could be causing the yeast problems on my 98 Ford ranger

[bob5731]

Could that be causing it to suck up too much air and make the engine act like it's stalling out. How do you get it off. I tried with a crescent wrench and I think it's frozen place.

 

[bob5731]

It's got a brand new downstream oxygen sensor.

Where is the fuse for the O2 oxygen sensor?

What could cause the O2 sensor voltage to not be recognized by the PCM?

I got the lean code today again.
P171

 

[Josh B]

I found a good 7/8in wrench to fit them quite well, simply get it a good grip and pop it with your palm, breaks em right loose

 

[RonD]

It's got a brand new downstream oxygen sensor.

Where is the fuse for the O2 oxygen sensor?

What could cause the O2 sensor voltage to not be recognized by the PCM?

I got the lean code today again.
P171

Upstream O2 sensor should also be new, if not replace it.

O2 sensors need to be above 650degF to work, so they have a heater built in, heater has a fuse, for 1998 Ranger try fuse #13 in engine fuse box, HEGO = O2 sensor heater

The Sensor part generates its own voltage, .1-.9v so under 1 volt, so no fuse

O2s have 4 wires, 2 for the heater and 2 for the sensor


"Lean", as far as OBD codes, means the computer is adding more fuel(opening injectors longer), than it calculated
The computer "knows" the size of the engine, so it knows how much air will come in at any RPM
The computer "knows" the fuel pressure and size of the injectors so it knows how much gasoline will flow out of each injector when it is opened for say 100ms(milliseconds)

So computer opens injector 100ms
O2 sensor looks at oxygen level
If high(lean)
Computer opens injector 102ms, then 104, the 106, then 108, ect..............
It does this until O2 reports .4volt correct oxygen level

If it got to or above 120ms, 20% higher than calculated open time, it would set a Lean code

ll this takes maybe 2 seconds, so engine is never running lean

So lean code means computers calculation are off, usually because unreported air is coming in, a vacuum leak maybe
MAF sensor is used to "weigh" the incoming air, if some air by-passes MAF sensor then air shows "light", i.e. like driving around in Denver(5,000ft elevation) so less fuel is added, and if you are actually at 1,000ft then Lean code

Computer expects 50-55psi fuel pressure, if its 30psi then less fuel flows out when injector is open for 100ms, so Lean code

If there is an exhaust manifold leak, air is sucked into the exhaust BEFORE O2 sensor, so O2 sensor sees that extra air as lean, but this is a false lean, so your MPG would drop and engine would actually be running Rich

 

[bob5731]

Freeze Frame Data.
P01711C
What could be causing a closed loop, oxygen sensor feedback to determine fuel mix?

 

[Dirtman]

That's a transmission code...

 

[RonD]

P1711 Tran Fluid Temperature Sensor Out Of Self Test Range

P0171 System too Lean (Bank 1)

Which one is it?

 

[bob5731]

I posted the freeze frame in the latest codes the other day. It's going back to that same mechanic tomorrow hopefully. If you all could help me out by tell me what to tell him to look for that would be great.

 

[Dirtman]

Word of advice... mechanics don't like to be told what to do by people on the internet.

 

[bob5731]

Ben how do I describe the problem to him?