cyl 6 lean?

[jeep72]

95 ford explorer 4.0 scan tool came up with cyl 6 lean. what could it be?

Topic

[Roy French]

I would look for a vacuum leak. You could also try switching the fuel injector with another one. If you transfer the problem you know you have a bad injector.

[jeep72]

could it be a dirty maf? or an o2 sensor?

[Tran]

Maf and O2s are not the main suspect in your case i think. Maf sensor when it bad it wil effects engine performing like too rich or too lean, rough idle, hestitation. For o2 sensor, hook up scan tool see how it switching. But again, your scan tool say particular #6 is the problem, i would look at the #6 area, vacuum leak, injector my be clogged up!good luck :cheer:

[college man]

since it is cylinder specific.check that cylinder for spark
and fuel.you could do a power balance test.do the test both
ways.spark and fuel.this should let you know which one.

[jeep72]

i still get a lean cyl 6 now with code 172 ?????

[college man]

try this link.

http://troubleshootmyvehicle.com/ford/4.6L-5.4L/troubleshooting-codes-p0172-and-p0175-page-1

[Jared Thomson]

I would guess that if it is only #6 running lean, its not going to be an issue with any sensors like the MAF or O2 sensors because those control the engine as a whole. I would look at the ignition and fuel injector systems on #6 as college man said.

[Paul R]

I don’t know how you would know cyl6 is lean.

code 172 172- Oxygen sensor not switching – system is or was lean bank 1
Since it’s a 95 it’s OBD I
OBD II code would be P0171 1996 and up (confusion by Ford)

Either way a common fault is a cold start vacuum leak. The intake manifold gaskets leak before the engine comes up to operating temperature. I don’t remember if you can get freeze frame data on a 95.

If you can, see if the code set engine cold. Sometimes it will be so bad the intake will whistle before it heats up.
Check for a vacuum leak with a dead cold engine.

[EricTheCarGuy]

As pointed out a 95 is pre OBDII and because of that I don’t think it sets ‘lean’ codes. Also, it wouldn’t be cylinder specific or at least I don’t think they had that capability in 95. That said, I’m with the group on looking for vacuum leaks as the cause of your engine running lean as it is the most logical place to start.

[ScannerDanner]

agree with Eric. There are no capabilities for single cylinder lean condition identification. you would need an O2 sensor for every cylinder. if you now have a 172 code this is a rich condition code not lean.
PO171 & PO174 = lean conditions
PO172 & PO175 = Rich conditions

First test I would do is check for a failing headset. Coolant contaminates the 02 and causes false rich conditions. also you can get cylinder specific and random misfire codes. Also you will NOT fix a P0172 code with a tune up…ever.

[Author]

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