rhenter

My 1990 RX-7 failed inspection for emissions. The HC reading was 205 but the legal limit in New Jersey is 173. I was wondering what is the quickest and easist way to get the car to pass inspection. I was told that HC is usually unburnt fuel in the exhaust so maybe the engine is just running too rich. The check engine light is on when the engine is idling and the codes from the light are 12, 13, 30, 33 (Throttle sensor (full range), pressure sensor (intake manifold pressure), split air solenoid valve, and port air solenoid valve.) I think the throttle sensor is the main problem and that might be causing the other codes. Is it possible that fixing the problem's that are causing the check engine light to go on will also fix the emmissions? can someone tell me the easiest way to get the emissions problem fixed?

gazellis

You may want to look at another thread called Failed Emission Tests posted by me. I am having the same problems with the high hydrocarbons. I don't have the check engine light problem though.



I have checked all vacuum hoses and repaired all leaks. I now think it may be running rich but I am not sure how to adjust that.

rhenter

it sounds like we have a similar problem. I don't have a problem with CO though and it sounds like my problem is with the TPS or the ECU. Also, is there any way i could just lean the mixture to pass inspection then put it back later. I have a bonez performance air filter that was installed by the previous owner. A friend told me that if the filter was dirty or if not enough air was getting to the engine, it could cause the engine to run rich. does anyone know anything about this? Is there anyway i could easily let more air in with the same amound of fuel to make the engine run less rich, even if it doesn't perform as well?

pmr2000

Are the cats in good shape? My 88 vert failed NYC HC only, new cats reduced HC by 90%. They looked good on the outside but insides were rattling.

gazellis

My Cats are brand new. I know it is difficult to change the mixture in these cars because it is controlled by the computer and depends on different sensors (Air temp, O2 sensor etc...)



You could check and make sure these were okay and functioning correctly. I did and it still did not help.



On another thread, someone mentioned about introducing a vacuum leak. This could cause the engine to lean out but it could also interfere with the TPS and the emissions.



Sorry I am not much help but I am lost about this also. My car is currently at another shop that passed my Dad's 85 pickup truck that really has no reason to be on the road anymore. I hope they can help me.

j9fd3s

the tps controls a lot of the emissions system, fix that and recheck it. the last two codes are for the air control valve which is another emissions part. on the 89+ cars there is no adjustability so you need to make the ecu happy



mike

IHEnter

I'd rather not go messing around with all the different sensors if i don't have to since i think most are pretty expensive to replace. another idea, if i took off the air filter for inspection or replaced it with a cheap paper one would that let more air into the engine thus making it run leaner or would the sensors just adjust to more air coming in and compensate with more gas. A friend told me that a dirty air filter can make the engine run rich but doesn't know much about rotary engines or fuel injection. anyone know if that would work?