emissions failure

[kitts95]

Ah,where to start. I live in illinois and took my 95auto to pass smog which of course, it didn't.I failed HC(.80 allowed,1.23 actual)no check engine codes at all. car runs good and strong.Took infrared thermo readings on cats,Inlets were 500 degrees,outlets at 380.Everyone said cats were bad.Got a system from sho shop in cali.,changed thermostat,plugs(all were clean),changed oil,two cans of heet in tank to remove moisture.So now the car seems to run stronger,I took it back for a second round,It is puking out more HC(.80 allowed,2.40 actual).The CO is up from the first test(7.4 up to 12.5)but that is still passing in my great state.I took thermo readings on these cats and the inlets are 330 degrees and 320 on the outlet.the car runs between the a and l on the temp guage. I think I covered and bored you guys with my problem enoughso if you have any suggestions I would appreciate it.

 

[Mels]

TRY the lowest octane gas you can find. Empty your tank (as much as you can) first. Retest running with the low octane gas. Works for me here in CT

 

[sdpatt]

Since you installed new catalytic converters and you are still not measuring a temperature rise across them, something is amiss with the engine control system. There should be a temperature rise across the cats of approximately 100F if they are "cooking" off the HC like they are designed. You mentioned you changed several items, but among them were not the oxygen sensors. These sensors are the only look the EEC has into the results of the accuracy of the air:fuel mixture and if not accurate, will cause problems such as those you are seeing. Try visiting this site to get an idea how the engine control system should operate and what the source or sources of your problem could be.

 

[LOUDSHO92]

Since your car is an auto you should have an egr. YOu should check the pipe going from the egr to the exaust manifold, there might be a leak in there.

 

[kitts95]

Thanks to everyone for the info. I have not changed the o2 sensors yet.I was told that these would pop a code if bad,but it is worth a try. I will also try the gas and check the egr system.I did not want to take it to a mech.because of what they charge but I don't have the equiptment to really dig in to it.I will let everyone know the outcome..... headbang

 

[kitts95]

I forgot one thing,Does anyone know what the temp.of their cats going in and going out.I am curious if these are about the same as someones that is emissions compliant.Thanks again

 

[SHOZ123]

The EGR only affects NOx emissions.