3.4 p0030 code
 

Ever since I bought the car it has thrown this code, I replaced both o2 sensor and am running out of ideas, does anyone else know what this could be? I have PCMSCAN and an obd2 interface on my laptop so I can scan or check everything myself and everything seems in order but it still throws this code after clearing it. The car gets TERRIBLE gas mileage if that helps.

Ive been fighting this code for MONTHS if anyone has ANY info please help!

RE: 3.4 p0030 code
 

try the PCV valve?

RE: 3.4 p0030 code
 

alrighty well since u have a scanner im guessin your know that the p0030 code is the HO2S Heater Control Circuit Bank 1 Sensor 1 which is y u replaced the o2 sensor...sensor one should b the sensor in the near the manifold (in front of the catalytic converter) if you have replaced the sensor i suggest checking the wires for the sensor

RE: 3.4 p0030 code
 

Yep replaced the sensor by the manifold, was an absolute pain in the rear but the code came right back after replacing it. Does anyone have a wiring diagram for the car? Ill try tracking it with my haines manual but I dont see that going well, if anyone knows what path these wires take it would be greatly appreciated.

RE: 3.4 p0030 code
 

Still no luck guys, I have tried everything! I did plugs, wires and a fuel filter today, has nothing to do with an O2 sensor, but it made no difference.

Please help!

RE: 3.4 p0030 code
 

Try your catalytic converter, I don't know if it is a testable item or not. GM may have a warranty on it still if that is the problem. What year is your car? Is it a '95-'97 with the 3.4 liter DOHC or is it an '00-'05 with the 3400 SFI motor?

RE: 3.4 p0030 code
 

Not sure how you would test the CAT, but its a 2001 with the 3400.

RE: 3.4 p0030 code
 

yeah I don't know if you can test it. lol.

RE: 3.4 p0030 code
 

The following codes were found using a GM Tech II scanner........

C1232 Left front WSS circuit open or shorted - I JUST replaced this wheel bearing.......
C1276 Delivered torque signal circuit (serial data problem) WTF is this?
C1245 Low tire pressure detected - fixed
C1298 PCM class 2 serial data link malfunction - I heard this means the computer is shot...

Any info?

RE: 3.4 p0030 code
 

My guess is that your PCM is bad or it needs to be reprogrammed. Wait and see if other members post on this though.