95 saturn SL1 stalling
About a year ago I started having stalling problems with my 1995 saturn . It stalled four or five times over a couple of months. The conditions are:
1) Always when warm. Never have problems when the engine is cold, but it does tend to idle fast first thing in the morning.
2) Never happens with full tank of gas. Problems start when we get down to a half tank.
3) No problems on flat ground or going downhill. When it happens, it is when the car is going uphill. A long, gentle slope is worse that a short, steep hill. It will typically stall-out just as I reach the crest. I can prevent a stall by dropping a gear (or two) at the base of the hill and keeping the revs up high. If I wait until it starts coughing and sputtering, it's too late. Dropping gears does not help, the engine can not get enough gas to recover.
Sometimes the engine light will come on, sometimes not. It will usually restart after two or three minutes, but I have to keep the revs up for the first few minutes until it settles down. I took it to the mechanic and he cleaned some of the fuel intact parts but basically did not find much. Finally he changed the fuel filter and "presto" the problem went away.
This fall, a year after the problem first surfaced, the problem is back worse than ever. I've had it in to the garage three times now. He changed the spark plugs and ignition wires and cleaned the injectors. Virtually no effect.
We thought we had it by changing the fuel filter again but once the gas tank dipped below half it happened again. This last time we had a rough time getting it restarted. The mechanic was able to recover an ERG?EGR? code this time and as a result cleaned some part that was gummed up. But I'm not so sure that this will fix the problem. Anybody have ideas on what it could be?