Teardown and inspection required to determine CAUSE.

Likely possibilities on #6 include:

-Hanging Thermostat on PORT bank
-Failure to warm up properly (Operator Error- Cold Seizure similar to above)
-Injector Problems (STRONGLY recommend Injectors be Serviced BEFORE reassembly)
-Reed Leakage/Failure

Be very cautious about rebuilds. Research the "builder"... their reputation, etc. That's a VERY low price (and if I were you, I'd want to know exactly what components are being replaced- ensuring they're OEM or TOP QUALITY ONLY).