I've been driving around for months with the SES light on. So I decided to get the o2 sims to put the light out. Plugged them into the rear, I took the car for a ride and it instantly ran bad, like it had a real bad miss. I went home, unplugged them. Took it out for a second ride, ran fine. Anyone have any ideas? BTW. Its a 99camaro ls1
Sorry im not much help, but I have simms in my rears right now and it runs fine.
my car has been running fine for 2 years on O2 sims? This may sound stupid but you sure you plugged them in the rears and not the fronts because if you did that would definitely make it run like @$$
__________________ 1998 Trans Am
Tuned by Frost Lid, !AIR, !EGR, LS6 intake, New Era ported TB, FIC 28.8lb injectors,
Mac Mids w/ORY and Magnaflow muff, LS2 timing set, LS6 oil pump, Taylor wires,
PerformaBuilt Level 2 4L60E, TCI SSF3600 stall, 24k cooler,
Eibach ProKit, Poly motor/tranny mounts, Black C5 wagon wheels, Drilled Slotted rotors w/Hawk pads.
o2 sims don't affect the air/fuel ration, they just tell the computer that the cats that aren't there are functioning properly. If you put them in the front o2 bung, that will make your car run like shit
I don't think the O2 sims are your problem. Suggestion go to auto zone, advance auto or something and have them scan the code. Then go from there. But I'm assuming you have headers which that doesn't matter. But when you put the headers on
1.) Did you change the plugs?
2.) One if not both of your 02's in the front might took a crap.
__________________ 98 Red Camaro SS M6, 226/228 .585/.588 112 LSA, P&P 241 Heads, GMMG Catback to CME, Kooks LT's and Catted Y, FTP 85mm lid, SLP 85mm MAF, SLP Flow Pac, LS6 Intake, Shaner S3 P&P TB, TB Bypass, SLP UD Pulley, 160 degree Thermo, LS 6 Oil Pump, LS2 timing chain, American Racing TTII 17X9.5, Hurst Billet Competition Shifter with Speed Dawg Ball
425rwhp/407rwtq
06 Cobalt SS/Supercharged Stage 2 Kit, 5-speed, GMPP Catback this is my DD.
I don't think the O2 sims are your problem. Suggestion go to auto zone, advance auto or something and have them scan the code. Then go from there. But I'm assuming you have headers which that doesn't matter. But when you put the headers on
1.) Did you change the plugs?
2.) One if not both of your 02's in the front might took a crap.
I don't see how the plugs or front o2's could be an issue being that he stated he went home unplugged the sims and went for a second ride and it ran fine, if they were the problem his car would still be running like crap. No matter the code the simple fact is he plugged in the sims it ran like crap he unplugged them and it ran fine again.....hence my theory he plugged them in the front on accident. Just my 0.02 cents
__________________ 1998 Trans Am
Tuned by Frost Lid, !AIR, !EGR, LS6 intake, New Era ported TB, FIC 28.8lb injectors,
Mac Mids w/ORY and Magnaflow muff, LS2 timing set, LS6 oil pump, Taylor wires,
PerformaBuilt Level 2 4L60E, TCI SSF3600 stall, 24k cooler,
Eibach ProKit, Poly motor/tranny mounts, Black C5 wagon wheels, Drilled Slotted rotors w/Hawk pads.
I don't see how the plugs or front o2's could be an issue being that he stated he went home unplugged the sims and went for a second ride and it ran fine, if they were the problem his car would still be running like crap. No matter the code the simple fact is he plugged in the sims it ran like crap he unplugged them and it ran fine again.....hence my theory he plugged them in the front on accident. Just my 0.02 cents
But what if one of his front 02's is going out? Just don't even think about the 02 sims. I've always heard about people saying the front 02's if one goes out then it will make the car run like carp. But I tell you about 2 months ago I had one starting going out on me and one minute the car ran fine and then the next minute it ran like crap and when the 02 started acting right it would throw you back in the seat and take off. An yes one minute the SES light came on and then it went off and it keep doing that a couple of times and then later on it just stayed on. Let me ask you a question have you had a front 02 go out? If you haven't I can tell you a ricer will kill you on take off, that gives you an idea of how bad the car can run if one does crap on you.
__________________ 98 Red Camaro SS M6, 226/228 .585/.588 112 LSA, P&P 241 Heads, GMMG Catback to CME, Kooks LT's and Catted Y, FTP 85mm lid, SLP 85mm MAF, SLP Flow Pac, LS6 Intake, Shaner S3 P&P TB, TB Bypass, SLP UD Pulley, 160 degree Thermo, LS 6 Oil Pump, LS2 timing chain, American Racing TTII 17X9.5, Hurst Billet Competition Shifter with Speed Dawg Ball
425rwhp/407rwtq
06 Cobalt SS/Supercharged Stage 2 Kit, 5-speed, GMPP Catback this is my DD.
Thanks for helping the new guy out.
I'll make long story short. I got the car with no motor, trans, or wiring harness in it. Got a new shortblock, put it all back togeather. heres were I went wrong. I had a piece of the harness draped over the top of the motor. in other words, what I thought was the front o2 plug was the rear. I got it all straightend out..and now I have reverse light too. I also have a set of o2 sims I dont need. I found out the code was turned out in the pcm.
But what if one of his front 02's is going out? Just don't even think about the 02 sims. I've always heard about people saying the front 02's if one goes out then it will make the car run like carp. But I tell you about 2 months ago I had one starting going out on me and one minute the car ran fine and then the next minute it ran like crap and when the 02 started acting right it would throw you back in the seat and take off. An yes one minute the SES light came on and then it went off and it keep doing that a couple of times and then later on it just stayed on. Let me ask you a question have you had a front 02 go out? If you haven't I can tell you a ricer will kill you on take off, that gives you an idea of how bad the car can run if one does crap on you.
Did you get your car fixed and was it an O2 sensor? I had no idea how shitty they will make your car run if one of the front (upstream) sensor's went out. I had them go out before but it was only the rear sensor and not the front. Looks like your an A4 an if the car studders and stuff like that on you, image how I felt when I'm an M6 and don't know if it's going to die or not and then out of now here comes the 400rwhp out of no where like a 300 shot of nitrous.
__________________ 98 Red Camaro SS M6, 226/228 .585/.588 112 LSA, P&P 241 Heads, GMMG Catback to CME, Kooks LT's and Catted Y, FTP 85mm lid, SLP 85mm MAF, SLP Flow Pac, LS6 Intake, Shaner S3 P&P TB, TB Bypass, SLP UD Pulley, 160 degree Thermo, LS 6 Oil Pump, LS2 timing chain, American Racing TTII 17X9.5, Hurst Billet Competition Shifter with Speed Dawg Ball
425rwhp/407rwtq
06 Cobalt SS/Supercharged Stage 2 Kit, 5-speed, GMPP Catback this is my DD.
O2 sims just given a constant Mv range to let the car to think it is acceptable. Get the car tuned, have the rears shut off so they wont be an issue. O2 sims are not a cure all, they work in some cases but not all.
__________________ 2002 Navy Blue Metallic Trans Am.
Pullin both wheels w/ 1.75 60's
Did you get your car fixed and was it an O2 sensor? I had no idea how shitty they will make your car run if one of the front (upstream) sensor's went out. I had them go out before but it was only the rear sensor and not the front. Looks like your an A4 an if the car studders and stuff like that on you, image how I felt when I'm an M6 and don't know if it's going to die or not and then out of now here comes the 400rwhp out of no where like a 300 shot of nitrous.
Yup, i changed the O2's and it fixed the problem. And i know what you mean with the car studdering, almost dieing, and then taking off like a huge shot of nitrous! haha
Thanks for helping the new guy out.
I'll make long story short. I got the car with no motor, trans, or wiring harness in it. Got a new shortblock, put it all back togeather. heres were I went wrong. I had a piece of the harness draped over the top of the motor. in other words, what I thought was the front o2 plug was the rear. I got it all straightend out..and now I have reverse light too. I also have a set of o2 sims I dont need. I found out the code was turned out in the pcm.
Thanks for the help.
Kudos to you for figuring out your problem. Enjoy the LSx world
__________________ Just an average LS1
Strano springs and sways, Koni 4/4's, UMI PHB .
417rwhp/383tq
12.02/113 on heavy 17/9.5 ZR1 OEM Concepts + MT/DR's
o2 sims make car run bad 
my car has been running fine for 2 years on O2 sims? This may sound stupid but you sure you plugged them in the rears and not the fronts because if you did that would definitely make it run like @$$
Machine 
