r_duff

So i was coming home from work, taking the sepulveda pass. I look down and notice my engine light came on. I just got gas 10 min ago, so i though maybe the gas cap wasnt on tight enough.

I pull over on a slight hill and check the gas cap. I turned it till it clicked (was already tight though). I go back to the car to turn it off and turn it back on ( i was thinking reboot at the time!) and the cel stays on. Now the CAR WONT START! Doesnt even crank.

Luckily, i parked on a hill, and was able to roll start it. I drive about 30 secs and my radio shuts off, 5 sec later, followed by my dash lights (lcd display lights only), 5 sec later folowed by my headlights. Window roll super slow and all lights are very dim. I drive home in the dark

Once home, i jumped my car to my other car and it starts and runs fine. Must be the battery. I replace the battery at autozone. Car starts and runs fine now... but the cel is still on.

I follow modifry's instructions on pulling the cel codes. I get:

2-0 ELECTRICAL LOAD DETECTOR (ELD)
4-1 Primary Heated Oxygen Sensor Heater Circuit Malfunction (Sensor 1)
6-5 Secondary Heated Oxygen Sensor Heater Circuit Malfunction (Sensor 2)

So both my o2 sensors are fried for some reason and the battery dies. Is this odd to anyone but me?

I did try the reset (backup fuse for 2 minutes), and the light came back on.

My related mods are:
CT supercharger, autometer boost and A/F ratio (yes i checked the t-taps; no OEM wires are cut). Spoon header. Mugen exhaust.
None of these were recent installs.

Anyone have any imput on what the problem is? Why did both my o2 sensor suddenly go bad? Which sensor is the one that goes in the header, and where is the other one (on the cat i assume?)?

Help!

DrDre1443

The primary is the header and the other goes right in the cat.

Experiences I've had with bad O2 sensors have been REALLY bad gas and the O2 sensors getting fouled. Pull out your sensors and take a look at them. It's as simple as connecting a spark plug socket to your wrench. Same size and comes out pretty easy (for the cat one).


I assume there have been no exteme weather conditions in your area like an ice age or the sun moving closer to your city? Do you stop at the same brand gas stations? Was it a random fill up? I assume with your FI, and modified A/F that even slight changes in anything could cause problems, so look at the immediate. Check the gas station, and if you can afford it, have a shop drop your fuel tank.

r_duff

what are the odds that both failed at the same time though?

r_duff

you think it was a bad batch of gas? interesting

Slows2k

Check for a blown ACG fuse 1st. Both 02 heaters and the ELD are on a common circuit.

This fuse can blow when the air pump control solenoid wiring gets cut by the drive belt.

David1

Dropping the fuel tank is not a good idea on an S. The whole rear bottom of the S would need to be torn down.

r_duff

ooh good call. I'll check that first. Is the ACG fuse under the hood or in the dash?

Slows2k

15A fuse #6 underdash fusebox.

r_duff

thanks sir!

1 more question.. is it ok to drive the car with bad o2 sensors? (if its not the fuse that is).

Slows2k

I'd bet on a blown fuse with that list of DTC's, or a open wire on the circuit before the splice to the 02's.

The sensors will still provide an input signal, just not have a heater element. They won't be accurate, nor will the PCM go into closed loop.