DethVenture

Long time lurker and poster. I recently purchased my first third gen, a 1992 Camaro RS with the 305 TBI, and it runs rich. It only has 102K original miles. I don't know all too much about the car yet as I have only had it for around a week now, so don't hesitate to ask questions. The catalytic converters have been deleted by the previous owner. It smells rich when running, the open element air filter is mildly greasy inside, and the throttle body had a mild amount of carbon buildup around the body and on the injectors before I cleaned it. The engine oil smells like gasoline when you pull the dipstick. Also, I'm unsure if this is related, but it sometimes has a small variation in the idle, usually less than 100-200 RPMs in variation, but enough to see it surging and/or fluctuating on the tach.

It runs good, drives good with no hitches, and is not throwing codes, but due to most of the above, it surely has to be running rich. Does anyone have advice? The P.O. deleted the cats, but I'm not sure if there is something that should have been done when that occurred that has been missed that could cause it to run like this.

I'm not sure where to start, so any suggestions are welcome!

Schurkey

HOW do you know it runs rich?

If the O2 sensor, TBI, and computer are still functional, the computer should be controlling the fuel mix. You'd see codes if the O2 sensor was unhappy-rich or unhappy-lean.

"I" would perform a proper and thorough tune-up, likely including an oil change. Verify that the PCV system works, and that the idle air control system works. As it's a new vehicle to you, I suggest a compression test on all eight, a leakdown test on all eight, and a cylinder-balance test on all eight.

At my house, new-to-me vehicles get ALL the fluids and filters changed, and those with computers get a scan-tool connected to look for weirdness.

First Guess: You don't like the exhaust smell? Time to re-install catalytic converter(s).

DethVenture

How would I go about testing and or verifying that the PCV system and IAC systems work?

Schurkey

IAC diagnosis is in the service manual you need to buy. The quickest way is to connect a scan tool, and verify that the engine actually idles at the RPM commanded by the computer.

PCV is easier--find the PCV valve, remove it. Shake it--it should rattle. Verify hose attached to the PCV isn't rotted. Re-install PCV into hose. Start engine. Put your thumb over the PCV valve--there should be strong suction. Find the fresh-air inlet filter for the PCV--probably in the air cleaner. Assure the filter is clean, the hose to the valve cover isn't rotted, and remove the fresh-air inlet hose from the valve cover grommet. With the engine still running, stick your thumb over the grommet. You should feel suction build in a few seconds. When you remove your thumb, the air will rush into the valve cover grommet. Put the fresh air hose back into the grommet. All is OK.

If the PCV doesn't rattle, if there's no suction at the end of the PCV valve, if the hose(s) are rotted, or if you never build-up vacuum at the other valve cover grommet, you have problems.