[PeteA216]

Ha, I remember that old picture.... it sounds as if it's running too rich. Like it's not getting a signal from the o2 sensor and the computer is thinking your running very lean and is trying to compensate. Check all the wiring to the oxygen sensor (1 wire)... it's possible that in the process of changing the head gasket, it was never plugged back in. Or, the wire may have burnt up on the exhaust manifold. If that is the case, the check engine light should have kicked on. To be sure the check engie light isnt burn out, turn the key to the on position but don't start the engine. If you don't see a "check engine" or "service engine soon" light come on then odds are the bulb burnt out.