My 1993 5.7 with the TBI has a really rich smell. It runs fine but you can really get a good eye burn if you stand outside while its running. I replaced the TBI with a rebuilt one I bought from e bay from guys that have a rebuild business. It runs better than the old one but still runs rich. I'm not aware of any mixture setting on these old TBI units. Anyone have any ideas. Ive replaced the temp sensor and the mass air flow sensor.

 

Disconnect the EVAP purge line from the manifold and cap the port, then recheck for a rich condition. If it’s gone, the purge control valve is probably stuck open.

If there’s no change, Remove the air cleaner and start the engine. Check to make sure the injectors are pulsing and not stuck open. You can use a stethoscope or long screwdriver to listen to them or put a finger on them to feel for pulsing.

If they’re not pulsing, check for a short to ground on the control circuits. Disconnect the injectors and ECM and use a test light from the B+ terminal to the dark blue & dark green wires - if it lights at all, the harness has a short.

 

excellent.... thank u