2003 Impala, no dash warnings, no known codes. When coasting at low speed the car will sometimes die. Never happens in park, never happens at highway speeds, never happens with throttle. Always happened more frequently at below about 5/8 of a tank of gas. Filling the gas tank also needs to be accomplished about a half gallon at a time as the pumps will shut themselves off constantly. Finally linked these two issues definitively after discovering that removing the gas cap to allow the pressure to equalize will eliminate the issue...for a time.

So what could this be, and is there anything else I can do to eliminate some possibilities before dropping the tank?


On a separate note, occasionally the left turn signal will blink rapidly as if it has a bulb out, but both front and rear blink without issue. This problem comes and goes. Any ideas?

 

Sounds like vapor lock. Unfortunately I don't know too much about the system so just a wild guess - evap purge valve?

As for the turn signals, make sure the bulbs and sockets are clean and the wires are good.

 

sounds like multiple issues, the pump kicking off during filling would point towards a venting issue. Do you drive on dirt roads or in dusty areas much? If part of the evap system is clogged it will make it very difficult to fill the tank and on farm/ranch vehicles its very common for the vent solenoid and canister to get filled with dirt


the stalling could be from a number of things but without codes or scantool data its hard to say