Ripoff. I went for smog check; I knew my van wouldn't pass inspection because the engine light was on. Let them run diagnostic for $50 to get an estimate for repair. They said $1658 to replace a lower intake manifold, including $1047 just for the basic part plus another $157 for the related parts (gaskets). This is not a typo. I price-checked the part on autozone's website: $430 for a complete set.
This place does smog checks for $10 so that's fine, but do NOT have them do any repair work unless you feel like setting your money on fire.