Sordid Tale of a "Service Engine" Light

mfaerber
Thu, 17 Jul 2008 14:16:28 +0000
Maintenance/Repairs

There’s a lot to my sordid tale so I’m going to try to be as brief and concise as possible:

Car Info:

1998 Ford Taurus station wagon V6 3.0L DOHC

“Service Engine Soon” light is ON. 140k miles. New spark plugs and air filter. Oil changed last week. Engine tune up and transmission flush about 3 months ago.

Got car inspected: FAIL.

Error Codes:

P0135 - O2 Sensor Heater Circuit (Bank 1 Sensor 1)

P0155 - O2 Sensor Heater Circuit (Bank 2 Sensor 1)

P1131 - P11XX Manufacturer Controlled Fuel and Air Metering (aka mass air flow sensor)

The Service Engine Soon light is ON. I live in NC. While visiting parents in VA last weekend went to their trusted mechanic. He replaced the two O2 sensors. I drove the car a few miles and the SEL came back on. Sent it back to mechanic. Mechanic had hell of a time finding the problem, some kind of “tree” test (this is a monroe muffler) and it pointed towards the O2 sensors again. He replaced all 5 O2 sensors including the first two he replaced (for free, he’s a great guy). In the end I think he forgot to do anything about the mass air flow sensor. At that point I had to go home to NC but on the way the SEL came back on. Took it to an inspection place and they kindly read the codes, all three original codes were still present. Guy looked under the hood and showed me that one of the air lines is ruptured. Went to Advanced Auto Parts and got new hose, attached it, disconnected battery for a bit. Next day after about 20 miles the SEL came back on.

All the while I’ve been told that the engine is running rich and that can screw up sensors. My question is this, can 150+ miles of driving with new O2 sensors and a ruptured air line (don’t’ know what the line is called, it is not very big or long) ruin my new O2 sensors? Frustrated, I bought all new sensors including the mass air flow one to try to resolve this on my own but I don’t want to ruin these sensors as well. Also I’ve read varying opinions on how to clean them (petrol, blow torch, etc.).

Thoughts? Opinions? Thank you in advance!

-matthew

326 posts - 26 participants