well my sedan has a gsr exhaust system and an ls motor and my ecu is throwing codes. i want to change my cat and downpipe back to an ls. i went to the junkyard and got the parts but the downpipe is longer than the one i have and the cat only has 1 o2 sensor (the downpipe has 1 o2 sensor too). the cat i have now has 2 o2 sensors and none on the downpipe. i was wondering if there was any difference between the coupe and sedan exhaust systems and if i got the wrong parts. thanks.

 

obdII Ls exhaust have one o2 on the header/ one on the cat. since the gsr headers are shorter they have both o2 on the cat thus making up the difference in length on the bpipe. coupe and sedans differences are only from the cat back.. since u have a gsr exhaust the LS header/ cat wont work with your current bpipe.

 

alright thanks

 

if i switch to obd1 with my current gsr exhaust on my ls motor would i pass smog?

 

you wont pass smong in california if ur car is obdII.. you cannont switch to obd1. why would u want to switch?

 

so ur exhaust is an obd2... and its also from a gsr. but uve got an ls motor?

well, ive had that setup myself on my ride. i too have a 4dr. did u check out what the codes were? cuz that would help. have the codes read.

what i did to fix mine was i resetted the ecu. and then.. took off both o2 sensors and just lightly dusted em off. then put everything back. it worked fine for me after that.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by exvtec94 &raquo;</TD></TR><TR><TD CLASS="quote">obdII Ls exhaust have one o2 on the header/ one on the cat. since the gsr headers are shorter they have both o2 on the cat thus making up the difference in length on the bpipe. coupe and sedans differences are only from the cat back.. since u have a gsr exhaust the LS header/ cat wont work with your current bpipe.</TD></TR></TABLE>


So a 2dr ls/gsr 'axle back' exhaust isnt the same as a 4dr one?

 

cool thanks a lot ill try doing that and the codes it threw seemed mostly exhaust and o2 problems so i hope this helps

 

axle back and bpipe are different between 2dr and 4dr.

 

yes they are.

however you can get any model 4 door exhaust to fit. also if you get a 2 door you can take it to a muffler shop and tehy can make it fit.

converting to obd1 will give you only 1 oxygen sensor.

but since your car came with obd2 you wont pass inspection.

how much did you pay for the pipes at the junkyard?
did it ever work, or did it suddenly start throwing codes?

 

its throwing codes as it sits right now and i got the ls exhaust pipes for about 110 total.

 

you probably have a bad O2 sensor if its throwing codes.