Check Engine Light - P0125

[Templisk]

Alright, I ran up to Savannah from Brunswick GA (1.5 hour drive or so) and the entire way I had cruise control going at 65-70 in 5th, AC on a good portion of the time letting in outside air with the compressor thing going.

My check engine light came on about 45 minutes away from Savannah, so I was stuck in the middle so I pulled off to see if I could see anything visually wrong. Being completely new to cars in general, and DSMs specifically I couldn't see a darn thing wrong with it. So I checked my fluids and everything appeared fine.

I took it to AutoZone and they ran the code thing for me and it came back as code P0125 something about coolant. My coolant level is fine, not sure when it was last changed (getting it to the mechanic on Saturday for a full inspection and replacement of all fluids and anything else that needs to be done)

My temperature gauge gets up to about half, but never goes any higher, and when the car has been running a while it never goes under. I get on the throttle pretty heavy in town getting up to speed, but I wasn't boosting any on the highway for a good 40 minutes after the last time the turbo spooled.

Unrelated possibly: I went to Savannah for a car alarm, got it installed (DEI Viper 690XV) and afterwards I noticed on the way home my boost gauge was no longer working (it is an Autometer gauge that came with the car) I can still hear the turbo spool, and the BOV let off and the car still *feels* normal.

Thanks for any feedback =)

 

[g_ferg]

generally there are open and closed loops which control the mixture settings of the engine. open loop happens when you do a cold start and the engine uses predetermined settings for mixture. when the engine warms up sufficiently for the o2 sensor to give correct readings it switches to closed loop operation, where the o2 sensor controls the mixture. often the coolant temp readings are used by the ecu to determine a good time to switch to closed loop operation. If the ECU thinks the engine is still cold, it runs in an open loop mode, quite rich




Cliffnotes: Time to get a new O2 sensor. Probably the front one.


PS...google can be a good Friend........