on my 92, I can't get it to pass. On HC (hydrocarbons) are 52.39, passing is .8. CO (carbon monoxide) is 312.3 passing is 15. I have a new catco cat and all emissions lines hooked up. Also have hooker AIR headers.

Jeremy

 

Wow, sounds like something's really out!

I'd look to the little things first, like the state of tune. Have you checked the timing lately? How about plugs/cap/rotor/wires/oil?
Having high HC like that, I believe, means that you're running rich. Somebody correct me if I'm wrong.

 

Make sure that your fuel pressure regulator is in good shape, if the diaphram is broken on it you will get too much HC(unburned fuel) in your exhaust. Now when your HC is high, your CO(lack of sufficiant O2 to make CO2) will be high because when you are running rich there is not enough oxygen to compleate combustion. I would do a fuel system leak down test, as well as make sure your AIR system is in good working order.

Make sure that your air filters are clean and your car is good and warmed up (in closed loop) and that your Map sensor and all vacuum lines are in good shape. Change your oil as well, as CO can originate in the crankcase.

Hope this helps,
Erik

 

Oh yeah...make sure you are running on all 8, as a dead miss will jack up your HC reading like a mo fackie... High HC is usally a mechanical problem...forgot to mention that.

 

OK, so a tune up and check Fp. I am running about 42 psi. I can't remember if this is stock. It is an adj reg so I can tune it. The fuel is not leaking down, but when I drove it there, it did seem kind of rough driving. The car has set a lot since Aug (only about 100 mi driven) so plugs may be gone. I hope this helps, I miss my car and a new top goes on this week.

Jeremy

 

this was the second test also, the first vet test was a little better, but not by much.

Jeremy

 

Don't forget changing the O2 sensor as part of the tune up.

 

running rich for sure. Gotta be in the basic tune. Idle air should be okay, but I would take it off and knock out the carbon. Usually high HC is due to carbon clogged emissions. If you have access to your EGR valve, take it off inspect and make sure its not carboned up.

 

new test results......
HC----15.05 passing--.8
CO----219.6 15
NOx--.26 2.5

Any more ideas

 

Maybe there's a clue in there somewhere

 

old sig, new catco cat

 

Do you have a low temp Thermostat ? That was my big problem. Also I agree with the EGR.....

 

.

 

180 themo, I will swap out the egr this weekend, I have a spare, right now I am replacing a oil pan gasket on a 2500 series truck. Its been one problem after another this year, and its only March

Jeremy

 

If you can, maybe run the idle a little high? I've heard that helps... like its supposed to idle around 750 rpm, right? maybe try to boost that to about 1000 or 1100 rpm. I'd also change the plugs and thermostat. I use a 195* thermostat on my car.

 

I am going to change the thrmostat today to a 195' After that, I might just take it to a shop .

Jeremy

 

may want to check tps voltage also.

 

You are running rich, check for vacuum leaks if your sensors check out ok. Bad injectors will make you get those reading also.