What would make my catalic converter catch on fire?

Question

I was trying to thaw out my windows the de-frost and engine
running. When smoke starts coming from undernith my vehicle.
the catalic converter was on fire, I put-out the fire with snow to save my truck. But what would cause this?

P.S. By the way It's a 1997 Ford Explorer.

Answer 1

The catalytic converter can reach very high temperatures under normal circumstances, which is why they tell you not to park over any flammable things. I've seen fires start when a car having problems pulls off the road into dry weeds.

Normally though, it doesn't catch fire unless: your exhaust was blocked with snow or ice, and the back pressure raised the temperature: or you are running way too rich and putting raw gas into the exhaust, but you should have a check engine light if that is happening.

Answer 2

Catalytic Converter Gas Fires

Answer 3

Rick it is going to be an oil leak. Plugging the exhaust causes no power and maybe even no start but it would not build the heat to a combustion state... ever, with snow and ice... its hot think about it. You have got to have something on the converter that is combustible to have it catch fire, such as oil or the floor is rusted out setting the under floor and carpet on fire. It is a dangerous thing so fix it before you burn it down.

Answer 4

That throwing snow on the fire put it out indicates it was on the outside of the convertor. Since the outside is metal, look for other items. Had you run over something (a paper bag, perhaps) and it got hung there? Are you leaking oil from somewhere and it gathered there? Check for oil and transmission fluid leaks that can run blow back there while you drive. As you see, these need to be taken care of. The CC gets quite hot to do it's job, and would be the most possible source of ignition.

Answer 5

The catalytic converter is for filtering the exhaust from your car. If you were to open it it would look like a bee hive. The exhaust passes through all these crevices until it make it out with somewhat cleaner emissions. Over time it will to clog with foreign material in the exhaust that adhere to the inside.

The exhaust is already hot so when it is blocked and does not allow the exhaust flow freely it becomes hot and can start to smoke. Cars sometimes catch on fire when they are parked on dry grass. The dry grass doesn't even have to come in contact with the converter to catch fire.

It's time to change or um...... add a welded piece of pipe where the converter is. Sorry!

Answer 6

Your engine is running too rich, meaning too much unburned gasoline is being dumped into the catalytic converter and being burned up there causing the excessive heating and fire. Has your yellow check engine light come on? If so, pay attention to it.
Read your service bulletin related titles for this problem below:

http://www.edmunds.com/maintenance/MaintenanceServlet
http://www.mycarstats.com/

Answer 7

It isn't the cat converter that actually catches fire. The cat converter works by getting really HOT. Cat converters are suppose to have mesh protector "over" to keep leaves (and other combustable material) away. But if your mesh protestor is missing, it can set leaves, etc. on fire.


Good Luck

Answer 8

Years of sloppy or non-existant maintenance. How long have you been ignoring that Check Engine light?

Answer 9

scan it ..how long has ck engine lite been on,,,bad sensor is screwing up fuel injectors,putting a rich mix...its 10 yrs old ...ever been tuned up??