Nessite helps with a 2003 Chevy

Someone can help me, I don't know what problem you have consumes gasoline and fails low as it sneezes the refrigerant, check the MAP sensor the potentiometer the IAC valve. It continues with the same does not generate codes and the spark plugs are always black already rectify the head valves and more. And nothing sometimes like she drowns you anymore to check for FA if someone can help me.

Doesn't it generate breakdowns codes? A little weird right? It could be due to a failure Lambda OA failure in the Motor Temperature NTC sensor.

Sometimes they give incorrect readings causing the enrichment of the mixture but sooner or later the switchboard finds a breakdown code.

Did you measure the % of CO? Have you proven the hermeticity of the injectors, it is not going to be that anyone is open? Have you proven to what pressure does the injection system work? just in case the vacuum regulator was wrong.

The bad thing about such a thing is that without a code that guides you where to start, you will touch you one by one all the engine sensors and compare them with the resistances and tolerances that the manufacturer gives. If you have oscilloscope or machine to take diagnosis, you can also test all digital sensors and impulse collection.

Another thing, to check the closure of the EGR, the best thing you can do is close the return of gases of the same manufacturing a blind joint with a sheet of a soda boat and replace it with the original joint. Thus, although the EGR valve opens, the exhaust gases will not return to the admission collector, so that if the failure persists, you can rule out the EGR action in the engine. Eye, this is provisional, do not leave the sheet put because you increase pollutant emissions.