QuestionLast night my engine light came on but the car was running fine... Today, I changed the oil and started the car... the engine light is still on and the rpms dropped from 800-1000 when parked to 500-600... When the gas is pressed, it hesitates to rev... any ideas?
AnswerHi Brian,
Could be anything from a loose gas cap, to an electronic problem.
Easiest and cheapest things to check are the EGR valve, vacuum leaks, fuel pressure, stuff like that.
It would be nice to have a scan tool code reader connected to see what code is stored.
on the bright side. a steady light usually just indicates a small problem.
There is a way to read codes on older vehicles, and yours may fall into that category.
Most parts houses will connect a scan tool and read the codes for you hoping you will buy any needed parts from them.
But there was no code for low fuel pressure back in 93 that I know of.
A lean or rich oxygen sensor reading doesn't mean the oxygen sensor is bad, necessarily.
A lean reading could mean low fuel pressure, injector problem, or vacuum leak.
A rich reading could be from dirty injectors, spark plug fouled, misfire, etc.
So don't just replace the sensor that the code indicates.
EGR valve could be stuck open, like sitting on a piece of carbon. They just need to be cleaned occasionally.
Van
