i unhooked the battery...(both terminals)
Low catalytic converter efficiency.
Your check engine light should come on. You will have poor performance from the engine, no get up and go.
1993 Chevy lumina: check all vacume lines for leaks and or splits around intake.AnswerIf you are not actually moving (just revving up the engine), it is normal for the engine stop at 4000 rpm. (governored)
The car will start and run poorly in the limp mode and the check engine light will illuminate.
Check actual engine temperature with a thermometer--if in acceptable range temperature sensor or gauge may be defective
If you live near a vocational school or career center, you might check their Automotive department. They might be able to help you out for a donation to the class.
Replacing the water pump will not cause the check engine light to come on. Either it is a coincidence or you have accidentally disconnected a wire or damaged a sensor somehow.
Check the vin #'s because in the 1990's Chevy called their smaller line of vans "Lumina" also.
Same place you check the fluid level.
check the fuse's first. then check the lamps [bulbs].....
go have your car serviced at the dealership. they can fix it.
Check the relay.