FORD WINDSTAR 1996 FAILED AIR CARE IN HC EMISSIONS AND NOx EMMISIONS

Hi!

First of all, HC (Hydrocarbon) are the residue of petroleum based product combustion. If your HC reading are higher than the OBD2 legal limit (220 ppm), the most common causes could be a leaking fuel injector, abnormal oil consumption, a faulty Oxygen sensor or worn out spark plug / distributor cap / spark plug wire. To be honest, I would need more accurate details such as NOx ppm, CO ppm, CO2 ppm and Oxygen ppm and if there is any repair that have been made on the car recently to give a proper diagnostic.

Warm regards

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

again, check the EGR valve, and the pcv valve,

Make sure you have no vacuum leaks and check/replace the Idle Air Control valve, its located on the side of the thottle body.

i would say change the O2 sensors and a new cat ,these readings are well over the top ,could have a exhaust blow on exhaust as well which will throw out the O2 readings

Did you change the air filter. The fuel filter will have no impact on emmision's but the air filter is a very common problem.If you usually drive it at low rev.'s then before you send it for emmisions test you will need to put it in a low gear and floor it for about a mile the reason is when it is being tested the engine is reved up to around 3500 rpm and any build up of unburned fuel or oil in the exhaust system will put up the emmisions reading.

Change the lambda/oxygen sensor in the exhaust.

catalytic converter most likely

If you failed you should know if it is HC, NOx, or CO. Posting that will make it much easier to diagnose.