FUCK FUCK FUCK!!!

I just got off the phone w/ the guy at the garage where I took my car. There are two garages w/in walking distance and I took mine to Sam's Auto Repair as they are across the street from one another and I couldn't make the turn to cross the street w/out stalling. Since I needed a close place, i didn't have time to check the Car Talk Mechanic Files. It turns out that Sam's ain't on it, but that's neither here nor there. I answered the phone and the guy (whom I can only assume isn't actually Sam) asked me how many months I'd been driving w/ the engine light on. I explained that it came on last summer, but I got the oil changed and added fuel injecter cleaner and the light went off (which is true). It turns out he assumed it'd been on for months because it's so fucked up. It needs a new exhaust system and some work on a couple valves... meaning a shit load of money I don't have. I was expecting maybe $600 in repairs... times that shit by 4. I really like my car, it's never given me any problems until now, and it's almost paid off. I don't know what to do. I checked the blue book value, and it's still worth doing I suppose, but fuck!