I failed my emissions test a week and a half ago because the carbon monoxide level was astromomical. I am in the process of replacing the catalytic converter and the thing is totally black. Something is causing these problems and I can't figure out what it is. I don't want to ruin the new cat I am putting on so I am asking anyone out there if they have any ideas what could be causing these problems. In addition the car does not idle smoothly and often surges when driving. I have ordered new plugs and wires but I don't think it will help.

 

If you have an SE, with fuel injection, the culprit may be the O2 sensor. If you have a carb, it is probably in need of an Overhaulin'.. Check with RX7Carl..

 

maybe alittle oxygen with the cat might be all you need.

 

My car is an SE. So, partsguy74, you think that it's the O2 sensor. Then that's where I'll start. Quagmireman - what do you mean by a little oxygen with the cat. Is there an adjustment to be made??

 

Don't know if the surging has anything to do with your emissions but it might be due to a vacuum leak. Make sure there are no vacuum leaks and if you have a carb, check to see if your ACV is working. Most all you need to pass is a working ACV (or air supply) hooked up to a working cat. Just do a search on the forum there's a lot of stuff posted about passing emissions; I even have a huge write up somewhere on this forum. Also make sure your mixture is set correctly (either too lean or too rich will cause the car to backfire).

 

The SE is fuel injected, so I will also check for the vacuum leaks. I read the writeups on passing emissions and did those things, but it still failed miserably, which leads me to believe it is something more perplexing.

 

The O2 sensor tells the computer what the amount of oxyget in the exhaust. This helps the computer determine whether to richen or lean out the fuel delivery. If the sensor gets coated with carbon and other exhaust debris, the sensor will not react quickly enough, nor read the oxygen levels properly. This usually leads to a richer fuel mixture. Which leads to a failed emissions inspection. Start there, then retest.

 

I hate to sound like an idiot, but where exactly is the O2 sensor located? I looked in the manual, but I couldn't find a specific reference to its location. I see you're from Erie. My hometown is Punxsutawney!

 

I don't have an SE, but all O2 sensors are somewhere in the exhaust stream between the exhaust manifold and the catalytic converters. It may be in the down pipe right before the converter.

Punxsutawney.. Good 4+ hours from erie..

 

It's on the exh manifold. Look for a wire going into the exh manifold. You prolly need to replace the cats anyway being it's 20 years old.

 

So the sensor is just a wire or is it some type of switch or plug?

 

It's a plug like sensor.

 

Oh cool, is that the picuture? That should be relatively easy to replace.

 

He he. It's not that easy. It's on reeeaaaalllly tight. It was easier for me to remove the manifold off then take it out. Have a muffler shop do it for you for like $5.

Yes, that the pic of it.

 

Thanks for the advice! Soooooo many things on these damn cars are so hard to do, but we do love them!

 

If someone else put it in, it's hard as hell to get out of any car... If you put it in last time, it should be easy to remove... Anti Seize is your friend.

 

Another bit of advice on removing it.. if you have some nice thick gloves.. soak the sensor with pb blaster, warm the car up to operating temperature, then try to remove it.. Use a nice boxed wrench or the special socket made just for it.. Hot metal expands.. should come out with a little patience.. (and maybe a few 2nd degree burns)...

 

Thanks again. I'll give it a try.

 

The problem was a vacuum leak as well as the TPS and other settings were out of wack! Fixed now and running great!

 

Damn straight!!!

Besides...i'm going in for a smog check soon, and I have a baaaad *** feeling i'm going to ge raped up the ***. I feel that my car is going to fail miserably. It's an 80' SA, so...I have to make sure my Air fuel mixture is proper....man...what the hell do I do?