check engine light

[Rui725]

Hey guys,

Unlucky night, dropped a girl off at her home, then when on the way back my check engine light came up.

Idles fine ( slight hovering between 700 and 800, but wasn't sure if this was normal) , engine sounds smooth, revved up real high

on the highway drive home, smooth as butter. My 1998 2.5 always had a small hesitation on 2nd gear around 2-3 rpm when i floor it from stopped position , very audible. 2 nights ago i ran the car hard for around 2 hours on mountain pass roads with a friend, engine temp was normal, took a rest on in the mid section for around 30 mintues, started the car and there was a audible clicking sound that was more audible by the drivers side. After revving it up a bit, the sound just disappeared. Ran it hard downhill to see if there any serious problems with the car, the car performed great. (note, at this time the check engine was not on yet). Drove the car whole day next day and the sound never reappeared again on start-ups, and i must have started the car more than 5 times that day. Going to get it checked out Monday. Engine oil normal, temp normal, idle fairly normal as far as i can recall, car runs great, engine idle sounding normal. Any preliminary guesses before I get the codes?

Thanks Guys

Rui

[Loren]

Without the fault codes - everything is a guess...

[Rui725]

Hi guys,

I'm back with the error codes

16 - Sensor aging behind Cat. Conv., Cy (1-3)

17 - same as above

95 - Shut off valve activated.

Mechanic cleared the fault codes for me and said to drive it more to see if it pops up again, if it does, will need to get new O2 sensors. Now note, i was conversing in mandarin with these guys, so the o2 sensor is a direct translation. For the above fault codes, what am i looking at here?

Relieved,

Rui

Edit* Just searched the forum, seems like a common fault with the sensor aging. The next time it pops up going to change it, or do you guys suggest just changing it now? Will I experience a decrease in driving performance or will it be bad for my engine?

Edited May 25, 2009 by Rui725

[Loren]

P1275 Aging of Oxygen Sensor Ahead of Catalytic Converter (Cylinders 1 - 3) - Below Lower Limit

P0139 Aging of Oxygen Sensor After Catalytic Converter (Cylinders 1 - 3)

Potential fault cause:

- Oxygen sensor

P0446 EVAP Canister Shutoff Valve (Function) - Below Lower Limit

Potential fault cause:

- Purge air line blocked.

- Flow resistance of EVAP canister too high.