OK, so here is the deal. My car is due for a state emissions test.The car was tested 2 years ago and did not pass.l managed to get a waiver for that time.But my 2 year waiver is up and the car needs to be tested again.l KNOW that the car is not going to pass.l had my boyfriend run a diagnostic on it this morning.(Not that l do not know how to do it, l just did not have the time).He pulled off the right kick panel and hooked up to the computer.He turned the car on to see what codes would flash via the Check Engine light.He said the only thing that happened was that the light did not flash in just remained on.Does this mean l have a bad/faulty ECU/ECM?l need to get this straighten out w/o taking it to the ''stealership''

Thanks
He did not hook it to a computer, it was a jumper near the ECM. But the MIL just stays on constant. We also tried the pulling back the carpet thing and could not locate a flashing LED light, or any LED light for that matter. l had suspucted a while back that my injectors were bad. l had them cleaned about two years ago (with the last emissions), when the car had 175k on it, and the dang car still did not pass. l also had the valves adjusted when l had the timing belt and water pump and such done. The reason l suspect it is running rich is due to the aweful exhaust smell, very rich in fuel, almost street rod like.
Thanks

there should be a two pin connector at the top & to the front of the kick panel. u need to jump the terminals then turn the ignition key on & read the blink code from the MIL. l do not know what 'computer' he hooked it up to as it is OBD l & not compatible with generic scan tools.

anyway, there will only be a stored diagnostic trouble code if the check engine light has been on. if the lights not on then the problem is not with a monitored component or system. Essentially that means u have a mechanical problem rather than an electronic control system problem

the history codes r erased after 80 key cycles from when they were last detected & the MIL is turned off. Again, if the MIL is not on or has not come on then u wo not get any codes out of the ECM

also, l think on that model u can pull the carpet back on the right floor & read the LED flashes on the ECM to get any codes that r stored.

hope that helps

edit: l just read the additional info on ur other questions.
if the car is running too rich do a fuel pressure test. u need to put a fuel pressure gauge inline & pull the vacuum line off the fuel pressure regulator. Then run the fuel pump by turning the key to the ON position. u should have about 40-45 PSI. then, use a pair of hose clamps on the return line to the tank to block it off & cycle the key off then on again. watch the pressure gauge. it should hold the pressure for 5 minutes. if the pressure drops then u have a leaking fuel injector. that will cause u to run ''Rich'' & fail emissions.

there r few reasons why the car runs rich--a leaking fuel injector is most common. You will also want to run a compression test to eliminate blow by as ur cause & make sure the valves r adjusted properly.

EDIT #2
l did some research; 1990 was the last year for the blinking lights on the ECM. 1991 went to the jumper wire & MIL to retrieve the codes.

as for the check engine light staying ON when the terminal is jumped that means there r no stored codes. If the check engine light does not come on when the terminal is jumped u either have a blown fuse or a bad ECM/PCM. Since ur check engine lightis staying ON when the terminals r jumped & the key then turned ON that means there is no problem with the ECM/PCM & there r no codes stored.

You can double check by pulling the 7.5 amp 'back-up' fuse in the underhood fuse box to reset the PCM. keep the fuse out for about 3 minutes before putting it back in. that will erase the PCM memory. then run the car & do the test for codes again. the Check Engine Light should come on & stay on when the test terminals r jumped & the ignition is turned on after the jumper is in place. That means there r no codes stored & the self-diagnosis system is operating properly.

sounds like everything is operating properly with ur engine management system.

as for the running rich, it definely sounds like u have a leaking fuel injector. There r many causes for running lean; only a select few for running rich. high fuel pressure could cause it but that is very rare; a disfunctional oxygen sensor could cause it but that would throw a code & u do not have a check engine light on. improperly adjusted valves could cause it but you've had them adjusted. The only other thing to check is the oil quality.

If l am right, the oil should be diluted with gasoline. pull the dipstick & smell it-- l am going to guess that u will smell gas in the oil. if an injector is leaking it will wash down the cylinder walls in the affected cylidner & dilute the oil. then as the engine is run the gasoline in the oil will evaporate & get sucked into the intake through the PCV & double ur source of fuel so that the mixture is rich both from the fuel injector & from the gas coming through the PCV. If u smell gas in the oi, change the oil & filter & see if the rich smell at the exhaust is reduced.

by the way, l doubt that all of the injectors r leaking. probably only one.