redraif
The uphill battle begins
2001 Sport 3.0L Auto 4x4... 240,000 stock OEM cats
Ok remember that I'm still new to this rig and the world of Mitsubishis...so if this is a stupid question I'm sorry!
What lead us to this point....
We already replaced the 02s twice on this beast. The first time was because the Previous Owner drove around for lord knows how long with codes for the EGR and O2s. The second time was due to the P0431 code and the tech finding irractic info on the scan tool for both O2s. So we opted for a second set of o2s. This helped for 150 miles & then the P0431 was back. The guess its because the PO did most of the damage to the cat by driving on bad o2s before we got it. So bad cat was the final verdict. Obviously once the cat is bad its only a matter of time before it plugs and either breaks up and dumps into the downstream cat and muffler or causes nasty backpressure and hurts the motor. So it has to be fixed sooner rather then later.
Good thing the precats are sold as "bolt in" individually. I refuse to do a weld in. Bolt on only! I read that using a budget bolt in will not last long (less platinum). So its top of the line aftermarket or OEM. Well OEM is ridiculous price wise. So I start looking at aftermarket.... well one guy on another forum mentions that the aftermarket units use crimp bends versus the factory mandrel bends... I'm not trying to restrict things further. So then I'm leaning back to factory... Then I start thinking... if the Drivers went out due to PO neglect isn't the passenger side soon to follow.... Then I will really be dropping some $. As it is we don't really have the spare cash to be dumping more into this after everything else we have had to do since November.
So I factor in what I'm planning for the truck in the next little bit. I plan to add a CAI for its minimal gains and add a flowmaster & shorten the exit pipe to infront of the tire... Yes for the ever so "slight" performance gain, but mostly for a better sound and to reduce the size compared to that MASSIVE factory one. Well replacing the bad cat will pretty much eat the budget I had to do the upgrades. So with that in mind my Dark side pipes in... just delete the precat dummy. Use the cash instead on the new exhaust. All the other cars in the family have a cat delete for performance. We have the x pipe on the Mustang GT (with mil eliminators), A straight pipe bolt in on the 87 firebird and Fiero... Why waste the $ on new precats.
So if I listen to my dark side and remove the factory monitored precat, what about the CEL light you ask. Well folks trick the ECM with a doubled up spark plug non-fouler. Pulls the rear most post cat o2 out of the exhaust stream enough to fool the ECM into thinking the exhaust is just fine. You don't mess with the front o2 as it suposedly talks to the ECm about what the engine is actually doing. They say the rear most "after cat" o2 basically monitors the cat's cleaning of the exhaust. So with that said, in theory, I could fix the CEL issue and eliminate the precats by adding non foulers to the "after cat" o2s. Then I could take the money I "would have" spent on the cat and have a shop make a bolt on "catless" off road version with O2 bungs and add the Flowmaster. Yes I shop is not supposed to disable emissions equipment. If I tell them to basically design it so everything is a bolt on like factory. I can save all my factory parts intact to take off and on at will. So with the bird, the story was to have the straight pipe to put on when "drag racing". With the Sport, I will tell them I want to be able to take off the cats when off roading so I don't crack a cat on some rut or rock while playing. Chances are it would end up cheaper. Then I could always go back to factory (new precat) "if" I want to sell it. Plus it would give me time to save up for the precat.
So now its time for you wise folks who have been there done that to tell me if its a good idea or stupid. I don't know much about the temperment of the Mistubishi's when fooling with Emissions equipment.
Is there any harm to come from doing this?
Will it tank my gas mileage, or make the truck run crappy?
Will it help with performance or just stay the same?
As always thanks you guys!
Ok remember that I'm still new to this rig and the world of Mitsubishis...so if this is a stupid question I'm sorry!
What lead us to this point....
We already replaced the 02s twice on this beast. The first time was because the Previous Owner drove around for lord knows how long with codes for the EGR and O2s. The second time was due to the P0431 code and the tech finding irractic info on the scan tool for both O2s. So we opted for a second set of o2s. This helped for 150 miles & then the P0431 was back. The guess its because the PO did most of the damage to the cat by driving on bad o2s before we got it. So bad cat was the final verdict. Obviously once the cat is bad its only a matter of time before it plugs and either breaks up and dumps into the downstream cat and muffler or causes nasty backpressure and hurts the motor. So it has to be fixed sooner rather then later.
Good thing the precats are sold as "bolt in" individually. I refuse to do a weld in. Bolt on only! I read that using a budget bolt in will not last long (less platinum). So its top of the line aftermarket or OEM. Well OEM is ridiculous price wise. So I start looking at aftermarket.... well one guy on another forum mentions that the aftermarket units use crimp bends versus the factory mandrel bends... I'm not trying to restrict things further. So then I'm leaning back to factory... Then I start thinking... if the Drivers went out due to PO neglect isn't the passenger side soon to follow.... Then I will really be dropping some $. As it is we don't really have the spare cash to be dumping more into this after everything else we have had to do since November.
So I factor in what I'm planning for the truck in the next little bit. I plan to add a CAI for its minimal gains and add a flowmaster & shorten the exit pipe to infront of the tire... Yes for the ever so "slight" performance gain, but mostly for a better sound and to reduce the size compared to that MASSIVE factory one. Well replacing the bad cat will pretty much eat the budget I had to do the upgrades. So with that in mind my Dark side pipes in... just delete the precat dummy. Use the cash instead on the new exhaust. All the other cars in the family have a cat delete for performance. We have the x pipe on the Mustang GT (with mil eliminators), A straight pipe bolt in on the 87 firebird and Fiero... Why waste the $ on new precats.
So if I listen to my dark side and remove the factory monitored precat, what about the CEL light you ask. Well folks trick the ECM with a doubled up spark plug non-fouler. Pulls the rear most post cat o2 out of the exhaust stream enough to fool the ECM into thinking the exhaust is just fine. You don't mess with the front o2 as it suposedly talks to the ECm about what the engine is actually doing. They say the rear most "after cat" o2 basically monitors the cat's cleaning of the exhaust. So with that said, in theory, I could fix the CEL issue and eliminate the precats by adding non foulers to the "after cat" o2s. Then I could take the money I "would have" spent on the cat and have a shop make a bolt on "catless" off road version with O2 bungs and add the Flowmaster. Yes I shop is not supposed to disable emissions equipment. If I tell them to basically design it so everything is a bolt on like factory. I can save all my factory parts intact to take off and on at will. So with the bird, the story was to have the straight pipe to put on when "drag racing". With the Sport, I will tell them I want to be able to take off the cats when off roading so I don't crack a cat on some rut or rock while playing. Chances are it would end up cheaper. Then I could always go back to factory (new precat) "if" I want to sell it. Plus it would give me time to save up for the precat.
So now its time for you wise folks who have been there done that to tell me if its a good idea or stupid. I don't know much about the temperment of the Mistubishi's when fooling with Emissions equipment.
Is there any harm to come from doing this?
Will it tank my gas mileage, or make the truck run crappy?
Will it help with performance or just stay the same?
As always thanks you guys!
