Hyundai sonata 2000 gls. v6. HAs no EGR. Emission test, first try, HC(0) CO (0) nox 1033 mechanic said my engine seems hot (there was also heat out of vents blowing out. I cleaned my maf sensor and put on high octane gas and fuel cleaner drove for a week and retested. ssecond try HC(0) CO (0) nox 1250. failed agian. I changed my mass airflow from anotehr car and change my 3 front spark plugs myself not the three at back. Car seemed to be running better and engine definitely cooler no more heat blowing from vent. Third test, I got hc 23 CO (O.O4) NOX NOW 3100. WHAT HAPPENED? it got worst but engine is alot cooler i can feel it.

Hyundai Sonata 2007 have the two variants which are Sonata GLS and Sonata SE. So check out the engine power of the Hyundai Sonata, which are as follows,

=> The Sonata GLS is powered by a 2.4-liter 4-cylinder engine that makes 162-hp and 164 lb.-ft of torque at 4,250 rpm.

=> The Sonata SE and Limited are powered by a 3.3-liter V6 engine that pumps out 234-hp and 226 lb.-ft of torque at 3,500 rpm.

The step by step procedure of changing O2 sensor in 2000 Hyundai Sonata GLS can be found in the following link:

http://www.ehow.com/how_7211340_do-sonata-gls-oxygen-sensor_.html

Sounds like you lost O2 Control

Check fuel trim & data with professional
scanner & such

You done as far as working at home, you did all
you can

You have a rich condition (CO)

Seems as though the coolant sensor is not working &
your in open loop

fist i would like you to post the year make and model of the truck along with the HC ppms and NOX ppm it would be very helpful but high hc and nox can be attributed to a faulty EGR system nox is produced when the combustion chamber temperature gets too high so a small amount of exhaust is cycled back into the air stream to help cool them there are other causes but without looking at the levels its much harder to say

1) please RUN the scanner and computer test from any repair shop you must get the exactly faulty in your emission system
2) However you can go to the www.automecanico.com+ www.autoelectronico.com this sites is in spanish, but you can translate with your web browser and I Higly recomend because has Powerful information update for any cars models, Try it and fix it.
God bless you

If the CO, HC, and O2 readings are average, then I still suspect the ERG is not being controlled correctly. The EGR should be cold at idle because the EGR ruins the engine vacuum at idle, so must be shut off. And get hot at mid range speed. You can usually feel it with your hand. If it is not opening, then try to manually open it. If it is vacuum, then put a vacuum to its hose port directly. It is it electric, then hot jump it. It is does not cause idle to drop, it is frozen or clogged.

If CO, HC, and O2 readings are below average, then the engine is just running too lean and that gets too hot. Check the sensors, temp, O2, an air mass. An ohmmeter reading of 0 or infinite is bad. The air mass and O2 sensor often are just dirty and need cleaning. PCV foam on the air mass sensor, and carbon on the O2.

what are all the reading ??? ALL 5 HC/CO/CO2/NOX/02

Change the lambda/oxygen sensor in the exhaust.

if i were you i would contact cragen and ask them if the car has it and how much the replacement part is