subie thread v2: running full 3" turbo back with no cat, cel, issues?
#1
subie thread v2: running full 3" turbo back with no cat, cel, issues?
i was told by the techs i work with, that i'll get a cel if i attempt to run no cat. i have found this to not be true. finished my ---- up tonight, ebay downpipe, steel flange, 6.5ft of 3" exhaust with some whitey bends and lack of actual bends, ending in a thrush turbo. sounds awesome for an awesome sounding car in the first place, but thats not the point. i need to know if i'll run into any issues
#5
Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
if its OBD-I and only has 1 O2 sensor, then its pretty much impossible to throw a CEL cause of it... if its OBD-II, then theres a second (rear) O2 sensor, specifically to see if its effectively running "leaner" AFTER the cat, basically voltages shouldnt be the same before/after the cat... there are ways to "simulate" a rear O2 if ya gotta pass a OBD-II test.
#6
Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
Originally Posted by c0mpl3x
i was told by the techs i work with, that i'll get a cel if i attempt to run no cat. i have found this to not be true. finished my ---- up tonight, ebay downpipe, steel flange, 6.5ft of 3" exhaust with some whitey bends and lack of actual bends, ending in a thrush turbo. sounds awesome for an awesome sounding car in the first place, but thats not the point. i need to know if i'll run into any issues
it will come up with a cel. once you clear it, it alwase comes back. ask me how i know this.
#7
Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
What all OBDII vehicles are looking for with the pre and post o2 is oxygen storage.When your car runs the readiness monitor for the converter they run the car lean then rich and look for a lag time between the front and rear o2.A working converter will have stored oxygen during the lean cycle and can use it to burn the unburnt fuel during the rich cycle.Also, all OBDII codes are 2 trip logic.If the vehicle runs the monitor for converter for instance,the 1st time it fails it sets a pending code.If it fails the same thing on the next consecutive drive cycle then the pending code matures and you get a MIL light.The only monitor that is one trip logic is a type "A" missfire which will cause the MIL to flash and sets on the 1st failure.
Theoretically you should get a MIL with no converter.
Mark
Theoretically you should get a MIL with no converter.
Mark
#9
Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
i took from turbo outlet to muffler off, there is only one o2, i think theres one in the uppipe but i dont remember. ill find out monday. anyways, i ripped on it for a good hour, no cel, unless it's a silent one.
it was started on and off about 4 times. moving to finish exhaust, at the gas station, at my friends, and getting pulled over for running a red light, which was yellow when i was under it. turned yellow on the stop line, *******.
it was started on and off about 4 times. moving to finish exhaust, at the gas station, at my friends, and getting pulled over for running a red light, which was yellow when i was under it. turned yellow on the stop line, *******.
#10
Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
Originally Posted by c0mpl3x
i took from turbo outlet to muffler off, there is only one o2, i think theres one in the uppipe but i dont remember. ill find out monday. anyways, i ripped on it for a good hour, no cel, unless it's a silent one.
it was started on and off about 4 times. moving to finish exhaust, at the gas station, at my friends, and getting pulled over for running a red light, which was yellow when i was under it. turned yellow on the stop line, *******.
it was started on and off about 4 times. moving to finish exhaust, at the gas station, at my friends, and getting pulled over for running a red light, which was yellow when i was under it. turned yellow on the stop line, *******.