Daughter's Car. Replaced Front O2 Sensors, MAF. She drove it for a while, started missing.
1-3-5-7 Plugs all fouled severely. Replaced all plugs and wires. Added Seafoam to tank. Examination of that O2 sensor revealed one wire slipped from connector. Replaced with new O2 Sensor (Bosch 15175)

Still missing and throwing these codes. - Note I cleared all the codes after installing plugs and wires.

P1884
P0155
P0300
P0304
P0154
P0135
P0308
P0102
P1300
P0306
P0302
P0306 PD
MIL ON
Monitors INC
Cat
Evap
Sec Air
O2 Sensor
Ready
Misfire
Fuel
Comp
O2 HTR

Service Engine Light Flashing

Help? She might have driven with Service Engine Light Flashing.

 

What spark plugs and plug wires did you use?
What grade of fuel is she using?
What brand of fuel?

 

Also waiting for his answer. Why at that mileage did you not replace all 4 02's?

 

agreed. what plugs and wires? and what fuel?

 

Earlier reply did not post.
Autolite Double Platinum Plugs, Advance Auto Parts Premium Plug wires (Advance Auto Parts less than 500 yards from home)
She is supposed to use Premium and does to the best of my knowledge. She uses whatever gas is close. Typically Pilot or BP, or local convenient stores.

Mike a good question. The original codes was only for Sensor 1 - 1 but I replaced both front units. I planned to replace the rears, but with all the codes, I'm not sure what to do.

BTW, when replacing the plugs I noticed the Crank Case Emission connection at the plastic Intake housing (Between MAF and Throddle Body) had broken loose. I repaired it and sealed it.

 

It is the plug wires.
www.apexperformance.net
Magnecor plug wires, your mis fire will not go away until you put those on.

 

So the plug wires will cause a misfire that throws a code on the O2 sensor that the heater circuit is malfunctioning?

Would I get these codes if the Cat is plugged/fouled?

 

Thanks Spike555 for the link. Wires should be here Friday.

 

On a LR 98% of O2 codes are because of poor engine tuning, in other words...you need a tune up.

When there is weak spark there is to much unburnt fuel sent to the O2's and it sets off O2 codes.
Those who dont know any better replace the O2's but the codes will come back unless you tune up the engine.

 

102 is your first problem. Did you use a factory install part. And is the engine a 4.0 or 4.6? Maf Sensors on 4.6 03/04 don't go. Plus using the wrong one will cause massive issues with everything.

And where did you get the oxygen sensors as well? Only factory stuff will fix problems. All the others will cause issues. I can't tell you how many times we have fixed issues caused by aftermarket and incorrect MAF and oxygen sensors. Trust me I am a technician.