89 pathfinder running rich Help Please!

[waybux]

I am a new member and this is my first posting so I apologize in advance if I did/do something wrong, kinda new at this.

 

My sister has a 89 pathfinder v6 auto, has about 190k miles. Recently the check engine light came on. We pulled the codes in mode 3 of the ECU, it came back to a code 55 (no malfunctions). In Mode 1 (o2 sensor function) the test came back with 5 flashes of green l.e.d. As I have read this should me that the o2 is functioning fine. In Mode 2 (air/fuel mixture) the red l.e.d. didn't come on, as the npora previous post stated this means its more than 5% rich. At this point I am assuming that this is what is causing the check engine light to come on. Oh, tune was just done after light came on, reset light and light continues to come on.

 

Any suggestions or help would be greatly appreciated.

[ejin4499]

I am a new member and this is my first posting so I apologize in advance if I did/do something wrong, kinda new at this.

 

My sister has a 89 pathfinder v6 auto, has about 190k miles. Recently the check engine light came on. We pulled the codes in mode 3 of the ECU, it came back to a code 55 (no malfunctions). In Mode 1 (o2 sensor function) the test came back with 5 flashes of green l.e.d. As I have read this should me that the o2 is functioning fine. In Mode 2 (air/fuel mixture) the red l.e.d. didn't come on, as the npora previous post stated this means its more than 5% rich. At this point I am assuming that this is what is causing the check engine light to come on. Oh, tune was just done after light came on, reset light and light continues to come on.

 

Any suggestions or help would be greatly appreciated.

If its running rich not enough air is getting into the cylinder or to much gas. I would start with replacing your air filter and running some sea foam through your brake vacuum line and take it for a drive. The sea foam helps clean out your intake plenum and the new air filter is less obstructive than the older one that is currently in there.

HTH

[waybux]

Ok I will try that today or tomorrow and see what happens. Thank you for your reply, I will post what happens.

 

 

If its running rich not enough air is getting into the cylinder or to much gas. I would start with replacing your air filter and running some sea foam through your brake vacuum line and take it for a drive. The sea foam helps clean out your intake plenum and the new air filter is less obstructive than the older one that is currently in there.

HTH

[silverton]

make sure your o2 sensor is also functioning properly.

 

you replaced plugs/cap/rotor right? if not, do those along with the air filter.

[waybux]

The air filter wasn't replaced, just visually inspected. It looked fairly clean but did smell of fuel a little. On the O2 sensor, I was thinking that was the problem initially, so we just did the ecu mode 1 test. I got the procedure from the forum here. It said to put Ecu in mode 1, then see if green led blinks 5 or more times while engine is running no load 2000rpm normal temp. The green led blinks 5 times so I just figured that meant the o2 was working properly. Is there a different/or additional test that you would recommend trying?

 

thank you for your time.

[sewebster]

O2 sensor could still be bad even if it passes the test I think... 5 doesn't really sound like so many. I'd rather have more than that. I assume it is in 10 seconds? I believe each flash is one cycle of the O2 sensor... if it is getting "slow" then it will not cycle as many times. Getting the bare minimum of 5 isn't necessarily so great. Of course, who knows, it could be fine, but...