Could a bad head gasket repair job cause o2 sensors to go bad and then your catalytic convers to plug? after having my car repaired I continued to have anti-freeze leaks and gasket leaks. the leak was fixed then my O2 sensors kept failing and replaced serval times. The I went to a misfiring issue to having my cats looked at and they check out fine. within a week my cats are plugged.

The Smell is-- Sulfur Dioxide-- from an over heated
Exhaust Converter

Yes-- it will be ruined soon

White Smoke all the time, could be a head gasket

It could also be-- lots of fuel-- that is overheating the converter

Have to look at fuel trim on scan tool data

Red hot catalytic converter is telling you engine is getting too much fuel. With a recent head gasket replacement check the following items MAP sensor this needs engine manifold vacuum to detect engine load high vacuum low output voltage and low vacuum high output voltage. Coolant contaminated oxygen sensors white powder color on sensor replace. or check voltage with red exhaust they should be around 900mv if reading 200mv or less they can be grounded out. check for missing sensor return ground loose or not connected. faulty mass air flow sensor readings, Throttle position sensor invalid. a scanner can verify sensor readings and help pinpoint ROOT cause.

White smoke is usually steam which would indicate a blown head gasket or crack in block. Hope it's something easier.

you have numerous problems to address, the cat could cause the car to smoke, but only because something is getting in it, heating up , and causing the smoke, normally if its white its due to water, and blue or gray due to a fuel issue , as far as a head gasket, if it was bad your cat could be bad too, so could the MAF sensor,, the alternator could work into this mess just due to the sensors not providing the correct signals to be sent to the computer in the car ,, but I doubt its bad , it can be simply checked, if you have a known good battery ,, use a meter and place the leads on the battery terminals, you should see a reading of between 13.5 and 14.5 volts, ( with the car running) if you do the alt is good, if not,, its probably bad,, There are two common types of mass airflow sensors in use on automotive engines. These are the vane meter and the hot wire. Neither design employs technology that measures air mass directly. However, with an additional sensor or two, the engine's air mass flow rate can be accurately determined.

Both approaches are used almost exclusively on electronic fuel injection (EFI) engines. Both sensor designs output a 0.0-5.0 volt or a pulse-width modulation (PWM) signal that is proportional to the air mass flow rate, and both sensors have an intake air temperature (IAT) sensor incorporated into their housings.

When a MAF is used in conjunction with an oxygen sensor, the engine's air/fuel ratio can be controlled very accurately. The MAF sensor provides the open-loop controller predicted air flow information (the measured air flow) to the ECU, and the oxygen sensor provides closed-loop feedback in order to make minor corrections to the predicted air mass.

I think you stated the "real issue" early in your description of the problem. You most likely have blown head gaskets! Especially if it has been reaching the temperatures you are describing - if it didn't have blown head gaskets or cracked or warped heads before, it does now! With combustion gasses get into the cooling system, the coolant temperature switch for the cooling fans will not work correctly. Your radiator fan will probably never come on until the head gasket problem is repaired. If you live in an area where you need to pass an emissions inspection, you are really going to be crying the blues when it comes time for inspection. Continuing to operate the engine with a blown head gasket not only causes severe engine damage from overheating, but also destroys the oxygen sensors and catalytic converters. So you will not only have to repair the head gasket problem just to stop your engine from overheating, but you will also have to replace your O2 Sensors and Catalytic Converters as well. Even if you don't have to pass inspection, you will be using twice as much fuel as you should because of the damage to the sensors and the catalyst caused by running antifreeze down the exhaust.

It could also be that the cooling fans not operating properly is the original problem. If so, this will also have to be fixed to keep it from destroying a high-dollar head gasket repair. However, it sounds to me like the damage has already been done if you are going through that much engine coolant. Trying to fix the radiator cooling fans without repairing a head gasket problem is futile.

....OR you can do like 90% of the people out there and just continue to run it until it plain won't run any more...then you can just paint "R.I.P." on the windshield and give it a decent burial!

P0430 means that the O2 sensor behind the catalytic converter is detecting that the catalytic converter is not functioning properly. This can be caused by a bad sensor, and exhaust leak or the actual catalytic converter is bad. Check for leaks 1st. The sensor is changed by unhooking and unscrewing it from the exhaust pipe, the catalytic will need to go to a repair shop. Hope this helps, let me know.

Sounds strange for all of that to be happening. The valve covers might need new gaskets. If you have a misfire, it could cause the O2 sensor to have a bad reading. Usually it's only 1 or 2 coils. (I would also replace the associated plug if they change a coil.) You could run it from there and if it doesn't clear up, then replace the O2 sensor at that point. Given the age of the car, getting the O2 sensor out may be a pain because it may be rusted/frozen in. Ford didn't believe in doing a good job putting anti-seize on the O2 sensor heads. Mine stripped when trying to replace an O2 sensor, so rather than have to replace a whole section of exhaust, I went to Midas and had them cut it out and weld in a new piece with a bung for the new O2 sensor.

Replace Catalytic converter or repair any damage to exhaust system.

Was a leak down test performed on the motor?This will determine if the oil loss is due to bad rings or a head gasket.A head gasket can be repaired,rings will require an overhaul or new motor.Have checked the coolant for oil contamination?

Yes the front O2 sensor(the one before the cat) could be lazy and cause this also.