Edawg2009

I have a 94 chevy 454 TBI having issues running rough and dying. I get a code I have DTC codes 13, 15, and 36. From what I've found code 15 is the coolant temp sensor that controls the warmup idle code 13 is the O2 sensor circuit but not sure how to troubleshoot the code 36 I've replaced the coolant sensor and gave it a tune up runs fine when first started but after it warms up and gets close to operating temp the engine sputters chokes. When it sputters and chokes it puffs grayish white smoke but smells rich. Any help appreciated

hanky

Usually the ECM controls fuel injector on time when the engine temp is below a certain temp (open loop). When the O2 sensor heats up and a certain amount of time passes,the computer uses the info from the O2 sensor to control fuel delivery amount.(closed loop) You could be looking at a malfunctioning oxygen sensor.

oilcanhenry

OBD I: could be:

OBD I 36. Ignition system – Circuit error/fault

It could also be an issue with the PCV system or the Mass Air Flow sensor if you have that.

Edawg2009

That was my next step i plan to check the O2 circuit first i have a repair manual to walk me through that however the O2 sensor was replace about 2 years ago but I understand it could have gotten damaged or such will let you know

Edawg2009

No MAF sensor on this vehicle

hanky

Maybe not as critical with some older vehicles as later models, but you would make out better with OEM oxygen sensors. Be careful purchasing supposed OEM parts online, lots of problems with counterfeit parts these days. Low price leaves chance for junk parts.

udidwht

94 will likely have 1 O2 sensor (single wire)

You'll also have a MAP sensor.

Code 36...Ignition circuit (ICM, pick up coil (removal of distributor), rotor, cap, Ignition coil (near distributor)
Could even be a bad TPS