[ayoleftyz]

OK, for the last three weeks my '97 Cobra's bitchy Check Engine light has been on, so I pulled my codes today and got the following:

P0151 - Heated O2 Sensor produced negative reference signal voltage (CHILTON'S MANUAL)

Upstream Heated O2 Sensor out of range/O2 Sensor Circuit Low Voltage (BANK 2, SENSOR 1) (INTERNET)

P1151 - HO2S Fault (CHILTON'S MANUAL)

Lack of Upstream Heated Oxygen Sensor switch, sensor indicates lean (BANK NO. 2) (INTERNET)

P1443 - Idle Air Control Valve speed fault (CHILTON'S MANUAL)

EEC - Vacuum System - Purge Control Solenoid or Purge Control Valve fault (INTERNET)

In case you didn't know, low voltage usually indicates there is too much O2 in the exhaust. Now, I am thinking either the two upstream O2's need to be replaced and are messed up, hence why sensor 1 from bank 2 is giving the out of range reading or possibly the IAC Valve is just in need of a replacement. This is where my dilemma is, I just need help identifying what to replace/fix and I don't want to spend $60 an hour for diagnostics to be performed and I sure as hell don't want to buy new O2S's if it's the IAC or vice versa. I'm sure you can understand where I'm coming from on that point haha. Anyways, any help at all is greatly appreciated, thanks!

[02whtstanggt]

If the IAC was causing a lean condition then both O2 banks would send codes. I think that your bank 2 O2 sensor is faulty. The car doesn't idle funny or act like it needs a IAC valve does it? If not I would just replace the O2 sensor and clear the codes and see if any codes return.

[coolwaterblvd]

Try spraying out the mass air meter element with MAF cleaner put die electrode grease on all of the electrical connections under the hood, then clear the codes and see if they come back after that then u may want to start replacing parts.

[ayoleftyz]

By clearing the codes you mean...? (just checking)

[coolwaterblvd]

Taking the computer error codes out.

[ayoleftyz]

Well, if the problem was indeed what you guys mentioned, wouldn't the codes clear themselves after a few driving cycles haha? I'm confused...

[rich96cobra]

you will need a code reader to clear the codes or unplug the battery for 10 minutes.

Rich

[ayoleftyz]

Alrighty, thanks a lot guys. I'll go ahead and replace the upstream O2S's and see if it fixes my problem *crosses fingers*.