Hello. I need some advice. I have a stock 89 Camaro RS with a 305 TBI in it. Vin E. I took my car in for emissions testing today and failed. After only a year of having it, I replaced my cat 2 weeks ago because it was clogged to the point where my car had a major loss of power. So I replaced it with a magnaflow cat because it was direct fit and was cheap. I think around $140. So the cat shouldn't be the problem. The guy at the emissions place told me that my car was running rich. I am attaching the emissions test result. Any kind of advice would be extremely appreciated.

 

have you ever changed the oxygen sensor?

 

I changed out the cat and did my O- sensor at the same time, just passed emissions last week. You might want to change it. Cheap fix.

 

Yes, it was about a year to a year and a half ago. I don't really know the life O2 sensors have. My car also has a lot of miles on it. I will try an 02 sensor in a few days. Is there anything else that ya'll can think of that I can try?

 

oops, can't figure out how to delete this reply.

 

Have u checked for codes?

 

My check engine light hasn't came on, but I will also check for codes.

 

A lot of miles will likely mean worn rings with blowby which will give you high HC numbers. At that point I don't know if there is anything you can do but rebuild it or get another engine. How many is a lot?

I have seen posts if you were close to passing to change the oil, retard the timing, plugs, wires, run a can of injector cleaner through, and make sure it was run a full 30 minutes before testing to make sure its hot. Also make sure it is getting up to temp as in correct thermostat. Change air cleaner.

You can get real crazy and get a hotter coil - couldn't hurt. Need good plug wires and make sure they are not arcing

 

Maybe take the air filter completely out for the test...

I would also seafoam the heck out of the car. Thru the tank, vacuum lines, TB, oil. If this has never been done, or not done in a while, this alone could very well make you pass the test. With a high mileage car like yours, its an even better idea.

I second what has been said though - plug wires, plugs, cap and rotor, things like this will definetly help, generally arent that expensive (unless you upgrade to performance parts), and could be causing it to run rich because the spark isnt as strong as it should be.

If the oil is dirty, change it. Try to run a lower viscosity oil like 5w or even 0w, ive heard this helps improve mpgs so it should also help you run a little smoother,less rich. (new cars run on 5w or 0w, almost all new hondas are 0w,because they are trying to get the best fuel economy possible) If im wrong about this, someone please correct me tho.

 

Your right in a sense. It does improve MPG to a point, 0w that is.

However most "new" cars run thinner oil is because the tolerances are so tight within the main/rod bearings etc. If its ment to run on 0w/5w from the factory, its because of the engine tolerances are made to work hand in hand with that specific weight of oil

 

A lot would be around 200k. Yes it does smoke a lot. My car is ragged but I have owned it for 10 years with no major real problems. I did drive it around for over 30 min before i took it up there and put some octane booster in the tank. I guess my next choice will be to do the tune up, change o2 sensor, i believe my thermostat is a 180 or maybe a 190 degree one. After I do all this I will post back on here the results of the retest. It will be next weekend but I will get back. Thanks again in advanced.

 

the aftermarket cats are not created equal, some do great at CO and NOx, but not so good at HC. others do great at CO and HC, but not at NOx.
without knowing what the pre-cat readings are, there is not way of knowing if it is running rich.
but from the numbers you posted, i would say it isn't. normally when its rich the CO will be higher.
a slight misfire will raise HC. burning oil fouls the spark plugs which can cause a misfire. it also kills O2 sensors and cats.
as was said by 308, dirty oil can raise HC and when you do the tuneup, pull out 1~2 degrees of ignition timing.
much more than that tends to cause HC and CO to go up, so clean and mark the timing marks and use a good timing light to check it before you loosen the distributor and again after you tighten it back down.
don't worry about what the timing specs say, go by the timing light to remove the 1 or 2 degrees.
sometimes you can pull up to 5~6 degrees and lower the HC even more, but without a 4 gas to verify the readings you wouldn't know, even with pulling just a little its a gamble at best without a 4 gas.

good luck

 

Definitely good luck, but if your engine is smoking, I don't think you will pass short of a rebuild.

 

Guess what? It passed. By 1 point!





Sorry it took so long to get back but I wasn't able to get retested until today (work schedule) So what I did was replace the O2 sensor, changed the oil, and changed the air filter. It wasn't too bad. But it looks like I'm gonna have to search for a new car by next year cause I don't think my car will pass again. My luck seems to be running out with this car. I really want to thank everyone for all the suggestions on here.