So, the cel came on a month ago, and I had the code read, a PO133, front O2 sensor. No surprise, but at least it's right there, no problem, a couple dozen bucks. And the car still runs fine. Now I've driven other cars for thousands of miles with that code so I'll do the O2 along with the PCV, plugs, wires, cap and all, soon. Then it rains like hell in tampa last friday and now the car idles rough, stalls when stopping for a light and runs rough at cruising speeds, say 50-70. Had the codes read at the local parts store today expecting to find more, but noooo. Only that pesky po133. So the question is, will that sensor really cause all those problems in this 850NA? If so , I'll pay full boat for that part and do it in the morning. Thanks

 

sure will. after all, it IS determining your air/fuel ratio.

 

Agree w/ibified, but you could also try this..

Unplug the front O2 sensor (will probably set another code) and see if it runs better (like before). If it does then run better, then it was definitely the O2 sensor.

If it doesn't then I would suspect you need plug wires, cap & rotor asap. And even so, do the O2 sensor as well; you'll get better pwr and gas mileage.

 

You are more likely to need the wires, cap and rotor in that order. For the most part I've never know water to make any difference in the operation of an O2 sensor or the lack there of.
I have tons of experience with wires shorting out early in the morning when a vehicle is parked outside and you notice "dew" on the hood or the grass or during or after going through rain or even a puddle. An easy way to check your wires is to lightly mist them with water from a spray bottle when the vehicle is running later in the evening when it's dark or in a garage (ventilate) with the garage lights off. If the wires are failing you can often hear them snap and will see them arc to a ground. Look but don't touch, trust me on this! If you don't get the wires to arc then it may be moisture in the cap. The cap can get moisture under it but if in doubt just pull it and the rotor and replace.

ASE mechanic.

 

Thanks guys. Ya know... I was wondering about that moisture thing. I once had a car that if I parked it on the grass it wouldn't run the next day. It had to be parked on pavement. But wouldn't that moisture burn off? Maybe not. It rains in Tampa every day. Anyway the O2 sensor is on the way, and I'll check that cap and rotor this weekend. And just wondering, where do you buy your parts? And is it necessary to buy OEM or Bosch parts? Will say, Denso or Beck-Arnley parts do? So next question, or maybe a thread. "Where do you get your parts?" Thanks again for the help, I don't know if I could drive this car without it.

 

For all the grief this thing has given me, the fix was the stupidest thing. So... after "proactively" replacing the O2 sensor (remember that pesky code) while checking the air filter I discovered a HUGE rip in the hose from the air box to the throttle body. Duh. Called the stealer. SIXTY BUCKS! and it's not in stock. And " we can have it tomorrow if you order before 2:30 but, we won't order it unless it's pre-paid and we don't take credit cards over the phone." Duct tape saves the day. Car runs great. Thanks again.

 

The duct tape will work for a while but due to the heat under hood the adhesive will let go sooner than later. You might want to try a couple salvage yards for that hose, less $$$.