i have a 1992 RS 305 TBI and it is not running in anyway shape or form the way it should. it doesnt want to crank and when it does it dies immeaditly when i can get it started it sounds like it has a hell of a cam in it and pressing the throttle causes back fireing like no other and hesitation. Its burning oil and he check engine light is on. the codes its throwing are 02 sensor coolant sensor and Electronic Spark Control and TPS. now the chances of all of thses sensors going bad at one time is vet unlikely considering they are all new and according tto the voltmeter working corrrrectly. i pulled the connection to the sensors and they are not getting the required 5volts, instead its getting about .5 to 1.5volts im begenning to think that the ECM has just decided to cut out which is underrstandable considering its 14 years old. Abou a week ago i had it running real nice i changed plugs wires dizzy cap fuel filter oil oil filter air filter but im kinda just stuck im out of ideas about what could be wrong. any help would be appriciated.

 

Welcome Aboard!

It seems that you have identified a significant problem. The fact that the TPS and other sensors are not getting the full 5.0VDC reference voltage is probably the root of most if not all your problems. Chances are the ECM is working properly, and the lack of voltage is a connection issue. Start by checking the sensor reference voltage right at the ECM. If the voltage is correct there, you can forget about a bad ECM for now. If the voltage is low at the ECM, you still need to verify that the ECM connectors themselves are clean and intact.

The next suspect would be grounds at the ECM harness, on the engine, and the negative battery connections at the engine and the body.

The fact that it was running well a week ago, before the change of plugs, wires, cap and rotor, would put those items under suspicion.

 

well i checked all the grounds and such and everything checked out so i decided to bite the bullet and buy a new ECM and voila problem solved, kinda all sensors are getting at least 5 volts now and it starts on the first crank no sputterring no backfiring but doesnt exactly have the power it should code 13 is still popping up so i am gonna swap the 02 sensor with a new one that i found i have laying around. under full throtle it bogs down but not under moderate to heavy throttle it sounds like its being starved for fuel any suggestions? and it was running well after the change of plugs wires etc so ive elimated those for the moment.