silly question, just curious

[mike h]

what would happen if you didnt tighten your fuel tank cap? it would mess with the pressure obviously but what would that do? bad gas mileage?

[firebird4u99]

Actually I don't think much would happen unless you were on a really steep hill. The fuel pump will pump the fuel regardless of pressure. Gas mileage is effected by weight, driving habbits and how healthy the engine is running which I'm sure you already knew.

[BLLDOGG]

i have heard that you will throw a code......

[mike h]

well i dont know what is wrong with my car but i havent seen an SES light in about a month even with all this misfiring crap going on. i think my ECU is slowly dying lol

[firebird4u99]

Sometimes my SES light wouldnt come on unless I drove for quite a while with it misfireing.

[mike h]

well the reason i asked the original question is that ive used a half tank of gas on about 50 miles since ive replaced my fuel pump, which is when i took off the gas cap. just wondering if the two were related or if the spark plugs were just finally crapping out about then.

[firebird4u99]

Most likely your plugs and wires. After you get the replaced use some Lucas fuel treatment or some LubraMollly Jectron and run a full tank through, then fill again and see how long that lasts under normal driving conditions. The results could be much better.