Volvo: Check Engine Light, volvo models, maria maria

Question
My husband a few weeks ago put some kind of mileage improvement/cleaner on my car.  He accidentally overfilled the tank.  Two days later my car stalled at a stop sign and the check engine light came on.  My husband asked me to put more gas in order to dilute that enhancer he had entered.  The day after I added more gas, the check engine light disappeared.  Two weeks later, after I put gas the check engine light came on again.  The next day at a red light my car stalled.  The next morning, the check engine light turned off.  A week later, at another red light my car shook a little and turned off.  I turned the car back on and the check engine light re-appeared.  My car is 10 years old and has about 180K miles.  I'm trying to get an idea of what is wrong before I take it into a dealer as it is a very old car and depending on the problem, might not be worth fixing.

Thank you,

Maria

Answer
Maria,
First you must read the fault codes and see what they are. Some of the Volvo models have a pre pump in the tank that could be inoperative and then the main pump has to pull fuel through a non working pump. That puts a strain on the pump and make the car in effect run out of fuel and stall. This is more of a problem as that fuel gets lower in the tank. Your main pump maybe getting weak and it just at times stops and that causes it to die.