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EF catalytic converter question

Any type of technical questions or info

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EF catalytic converter question

#1 Post by Eric » Tue Sep 12, 2006 11:57 am

Ok i know its not rotor-related, but its not breaking any rules.

Got a 1996 EF wagon thats been running like a dog lately and it looks like it might be a blocked catalytic converter.

Took it down to the exhaust place (it needs the rear part of the exhaust after the muffler done anyway because its rusted), and got told a new catalytic converter will cost $300, and the section of exhaust another $150.

My question is, are there any sort of sensors or anything for the catalytic converter, and will the ECU really care if there isnt one?
Or will it go into freakout mode?

Seems like a waste of money to replace it if i dont need it thats all.

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#2 Post by KYPREO » Tue Sep 12, 2006 12:03 pm

I don't know anything specific about that car, but generally the closed loop catalytic converters have an oxygen sensor much further upstream - usually in the main pipe after the headers collect. If the 02 sensor is missing or faulty, it will usually cause an ECU to go into limp mode and do some crazy things.

Removing that cat shouldn't have any affect on the computer so long as the 02 sensor is still there and still works. Sometimes cat convertors have air pipes associated with them that you need to deal with, but I would guess here it is just a straight cat.

Obviously the authorities will care if there is no cat.

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#3 Post by Slides » Tue Sep 12, 2006 12:13 pm

mechanic mate replaced one (exhaust not sure if new cat) last week i think (on EF falcon)

i was hanging around (i actually help them a bit so his boss likes me) and as far as i can recall they did not have a sensor after the cat so it should not hurt. if you are not sure just look under the car

and with no cat you have less back pressure which should mean slightly better performance/economy

and for those people goin oooo bad fumes, piss off even new diesels spew out much worse stuff, all those micro particles from the diesels are absorbed through your lungs and go through your whole body(in the US they are really starting to worry about this especially in California), yet people are espousing the value of diesel power vehicles in city/suburban environments with lots of people around :roll: and it isn't even economic for most soccer mums anyway as they would have to be doing 30 000km a year and keep them for 9 or 10 years to break even with fuel at $1.50 :evil:

and if its a stocker running low octane(normal) fuel there will be fuck all cyclic alkanes/kenes (the bad ones) getting thorugh combustion anyway as there is fuck all in the fuel to start with.

obviously you would want to bash out and leave the old cat body so you could say it must have died after you got the new rear section, i don't think many cops/epa people would try and do you for it unless it was very sus(thats why you leave dead cat on there instead of straight pipe), and it isn't as if you have a high chance of anyone looking anyway. The cat on my mums ~94 magna died recently (buzz buzz buzz) and there is no way we are gonna pay for another one unless the body of the cat rusts through (unlikely) :wink:

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