I have a 97 F150 w/ 4.6L that was recently rebuilt. After the rebuild I smell something that smells hot and have been told it is the cats (even though I don't smell the dreaded rotten eggs smell). My check engine light is on most likely because of a bad O2 sensor.

Are the smell and bad O2 sensor related??

Next, I am putting on a Gibson SI/DO system real soon and am wondering if the cats are in question, should I replace them now??

How much are new catalytic converters and where could I buy one (preferably not ford due to the price inflations)??

Finally, is there anything that can be done to the cats to element this smell and not have to buy new ones??

Ideas, thoughts, or suggestions would be greatly appreciated.

Thanks, Matt

 

If the cats are bad, it's very obvious. The smell is terrible. You can also tell if they are crumbling by hitting them with a mallet. Bad cats rattle.

Since the engine was rebuilt, it could be that they didn't reconnect the HO2 or some other sensors so you may just want to check that to begin with.

If you don't have a code reader then you need to get one right away to confirm that it is the HO2 sensor causing the MIL. You can end up spending hundreds of dollars replacing perfectly functioning sensors.

Another issue to be aware of is that your cats are warrantied for 8 years or 80,000 miles so Ford will need to replace them if they are in fact bad and you're within the milage limit. On my 4.2L the cats are around $1500.00.

Aftermarket, highflow cats are around $200.00 each.

A bad HO2 sensor will make the engine run rich and hot because the computer doesn't realize you've reached normal operating temp. This could be what you smell. You could smell all sorts of things if the engine is running hot.