On 11/30/16 I was driving through heavy rain and my 1993 GTP stalls . I get it pulled over on the side of the road and try to start it. It idled but only when I fed it gas and then it would stall. I tried starting it several times but it would only stay running when I feathered the gas pedal and it would sputter and back fire when doing so. I had it towed to a small shop where a friend is the service writer. One of the mechanics checked for codes and found about 7 of them. He cleared them and they returned. Its unlikely that all of these things happened at one time? I've had this car for 17 years and it no longer has the 3.4 it has a 3.1 that I had installed with only 19,600 on it. It now has about 23,000 on the engine and about 195,000 on the car. The mechanic doesn't know where to start because it would cost so much money to chase all of the codes. I don't want to give up on it now. So my question is where should I go from here? What to check first etc.? Please help. Thanks