The belt popped on my car, it was replaced, and then it threw a p1415 code. The maf was replaced, and now i have a p0171 and p0174 code. I know what the codes mean (running lean) but i still can't find the problem. I made a home made smoke machine, and the only leak seems to be coming from the crankshaft pully. Im not sure if maybe a shard of the belt messed it up. The car is now idleing around 600-750 rpm's, and starts to surge in 100+- intervals. Everything is pointing to a vacuum leak, but there is only the one. Any help would be appreciated on helping me fix this, its been almost a month, its been to a shop, and thy cant fix it either. HELP!!!!