No "check engine light" with headers!!!

honestly, this is a very costly route compared with a $40 o2 sim. i installed my o2 sim in the ecu compartment, wired into the harness. no check engine lights, all monitors are ready, and i saved the $140 or so the innovative costs, plus avoided having to weld in a bung and install the wideband. to each their own, though.

Originally Posted by bryce-o

honestly, this is a very costly route compared with a $40 o2 sim. i installed my o2 sim in the ecu compartment, wired into the harness. no check engine lights, all monitors are ready, and i saved the $140 or so the innovative costs, plus avoided having to weld in a bung and install the wideband. to each their own, though.

Depends on how long you want the "fix" to work. If its just long enough to pass inspection then sure, $40 and done. I prefer to do it right the first time and have to light off instead of driving around with a CEL and constantly checking my codes to make sure nothing else pops up.

Originally Posted by E46_330i_Stud

Depends on how long you want the "fix" to work. If its just long enough to pass inspection then sure, $40 and done. I prefer to do it right the first time and have to light off instead of driving around with a CEL and constantly checking my codes to make sure nothing else pops up.

i've had the o2 sim solution for several thousand miles. aggie46 did too, for much longer than me.

on my 135i and 335i, i had a similar o2 sim work for years with no issues, with my catless downpipes.

not sure where all these "facts" come from about an o2 sim being temporary, just to pass inspection.

i've always viewed them as complete solutions, regardless of mileage or # of inspections.

For the record, I first attempted an O2 sim but could not get my CEL to turn off. An LC-1 solved the problem that O2 sims could not, at least for me.

well, it's most likely user error. our cars are all wired the same. if installed correctly, an o2 sim will keep the CEL off, allow readiness to be set, and emissions testing to be passed indefinitely. i've never experienced any issues using o2 sims. no CEL, not codes, no problems.

Originally Posted by bryce-o

well, it's most likely user error. our cars are all wired the same. if installed correctly, an o2 sim will keep the CEL off, allow readiness to be set, and emissions testing to be passed indefinitely. i've never experienced any issues using o2 sims. no CEL, not codes, no problems.

No. No, no no. It has everything to do with typical usage routines and driving styles/habits. Not every car 'adapts' the same.

If you're not here to contribute to the information and discussion initiated by the OP then please leave. I have used both, wired correctly every time, and the O2 sim WILL fail eventually. I don't care if you pretended to be impartial in your first post, you keep following-up with people who did nothing but answer your question, blaming them for not knowing how to wire something in. Yet these are the people who installed LC-1s.

My O2 sim threw codes within 170 miles of driving on highway. In the city, no problem. But any highway trip over 40 minutes and BAM, codes.

A programmable curve output is the only complete solution, period.

Originally Posted by deadwood83

No. No, no no. It has everything to do with typical usage routines and driving styles/habits. Not every car 'adapts' the same.

If you're not here to contribute to the information and discussion initiated by the OP then please leave. I have used both, wired correctly every time, and the O2 sim WILL fail eventually. I don't care if you pretended to be impartial in your first post, you keep following-up with people who did nothing but answer your question, blaming them for not knowing how to wire something in. Yet these are the people who installed LC-1s.

My O2 sim threw codes within 170 miles of driving on highway. In the city, no problem. But any highway trip over 40 minutes and BAM, codes.

A programmable curve output is the only complete solution, period.

i'm not trolling or trying to be disrespectful. i was just giving my perspective.


i've had 5-6 cars that were catless by modification. on most of the cars, i used o2 sim type devices (electronic resistors wired into the ecu harness). the n54 twin turbo is even more sensitive and hard to fool than the m54/s54 engines. on my 135i and 335i, i never had any issues with a $40 o2 sim. several years, tens of thousands of miles, no codes or issues.

on my e46, i used the same technique. wired in an o2 sim into harness connected to the ecu. so far, about 6k miles with no issues. yes, i have a long commute that's about 50 miles each way, highway miles. yes, i've also gone 330 miles one way (there and back, 650 or so combined) on a road trip in this time frame. no codes or issues.

for the guys that want to be competely thorough, the lc-1 is a proven solution. for guys that have experience with other bmw's outside of the e46, we know that an lc-1 is not necessary to run catless, regardless of driving style, distance driven, or any other factors.

it may be easier and more reliable to just pony up the $ for the lc-1, plus the necessary welding and wideband o2 sensor installation. i was just pointing out that it's not required, that's all.


cheers

I have tested all sorts of o2 "sims" and it comes down to what the DME is looking for. The .650 volts that 99% of most o2 sims produce works on most cars that just look for good operating cat voltage. But when you let off on the gas and go into fuel cut our cars look for the lean signal and how long it took to get it. What is this $40 o2 simulator, tell me more about it. You say it is just a resistor wired to the DME harness, that sounds pretty vague. I have used the LC-1 on a 135i with great results, I don't see how your o2 "sim" worked on that car. I am going to need to see more information before I believe this claim. For $40 I'll buy my own and test it out.

Why do you need to weld another bung in? You have 2 useless holes in the headers down stream lol

Originally Posted by F1004fun

I have tested all sorts of o2 "sims" and it comes down to what the DME is looking for. The .650 volts that 99% of most o2 sims produce works on most cars that just look for good operating cat voltage. But when you let off on the gas and go into fuel cut our cars look for the lean signal and how long it took to get it. What is this $40 o2 simulator, tell me more about it. You say it is just a resistor wired to the DME harness, that sounds pretty vague. I have used the LC-1 on a 135i with great results, I don't see how your o2 "sim" worked on that car. I am going to need to see more information before I believe this claim. For $40 I'll buy my own and test it out.

This is what you need for a $3.00 O2 sim. You solder the resistor and cap in paralel with each other,then wire those as the sensor circuit,leaving heater wires hooked up where they were. This will stop the CEL,but in my experience will not allow post cat signal to be "ready". And after a long trip-100 miles or more,the may throw a code. DD is no problem though. I installed mine on my old 330 just after the connector under the valve cover-cover. Works,but not a 100% solution.


sent from my ATARI sc1224

This thread isn't about an "occasional check engine light" with headers. This is about a solution, "no check engine light" all monitors passed.

Originally Posted by F1004fun

I have tested all sorts of o2 "sims" and it comes down to what the DME is looking for. The .650 volts that 99% of most o2 sims produce works on most cars that just look for good operating cat voltage. But when you let off on the gas and go into fuel cut our cars look for the lean signal and how long it took to get it. What is this $40 o2 simulator, tell me more about it. You say it is just a resistor wired to the DME harness, that sounds pretty vague. I have used the LC-1 on a 135i with great results, I don't see how your o2 "sim" worked on that car. I am going to need to see more information before I believe this claim. For $40 I'll buy my own and test it out.

http://www.burgertuning.com/dpfix.html

it's called the dpfix. it's $80 from burger tuning, or $40 from the classifieds on e90post.com/1addicts.com (used). EVERYONE uses that o2 sim on the n54 platforms and have the exact same results as me. no codes. no issues. no pending codes.

people with cobb accessports, vishnu procedes, other flash tunes, and the burger jb4 all know the dpfix works for setting readiness, avoiding codes, and generally speaking is an end-all solution for running catless downpipes on the twin turbo cars.


i have put literally 50k+ combined miles on n54 vehicles with that dpfix. no codes, no check engine lights, even when driving (and coasting) on 330+ mile road trips. 3 different passes on state inspection testing, which in texas, consists of checking readiness on the 7 or so monitors.



for my e46, i purchased a dual bank o2 sim from o2sim.com. installed it the same way as the burger tuning dpfix on my 135i and 335i (wired directly into the ecu harness in the ecu compartment). just like my twin turbo cars, my e46 has been driving substantial mileage with this solution, and on a few longer distance road trips. plenty of driving, coasting, etc. i haven't gotten any codes, pending codes, or any other problems from using the $40 o2 sim from o2sim.com



i'm not knocking the use of the innovative lc-1; it's obviously a proven technique to set readiness and pass inspection. again, i'm just giving my experience on the e46/e82/e90 platforms. wiring an o2 sim into the engine/ecu harness has worked perfectly fine for me, over 3 years, 50k+ combined miles, on 3 different cars.

ultimate solution: go to a muffler shop and have them weld in two cats into your mid pipe, 100 to 300 cell should do the trick, then install the bungs at the correct angles. never worry about smog, or lack of performance, no CEL and no problems with the boys in blue, unless you have your car reffed, and they see that you've moved your cats, which in CA is mostly illegal, but this works every time. your O2 sensors do their jobs, your car keeps itself in check, no stupid witchcraft simulators, and no fuel mixture problems. can be don for under 400, which is still way better than paying the 2000+ for a new big name exhaust system with cats. as a gift to yourself, before installing your ebay headers, go ahead and take a dremel to the inside to finish them out.

Originally Posted by Bandit4077

ultimate solution: go to a muffler shop and have them weld in two cats into your mid pipe, 100 to 300 cell should do the trick, then install the bungs at the correct angles. never worry about smog, or lack of performance, no CEL and no problems with the boys in blue, unless you have your car reffed, and they see that you've moved your cats, which in CA is mostly illegal, but this works every time. your O2 sensors do their jobs, your car keeps itself in check, no stupid witchcraft simulators, and no fuel mixture problems. can be don for under 400, which is still way better than paying the 2000+ for a new big name exhaust system with cats. as a gift to yourself, before installing your ebay headers, go ahead and take a dremel to the inside to finish them out.

Wow, I can't believe people have been struggling with this for years and nobody ever thought to give this a try. Oh wait, they did... and they still had problems. Unfortunately the issue is more complex than you realize. Perhaps you need to spend a little more time reading old posts.

Hi all, I've been lurking around for a few years since buying my 330. usually im very active in forums but the bimmer has been so well documented and easy to find access to.. up till now!

Bandit, Its NOT that simple. aftermarket cats don't work nearly as well as you say. Some cars get lucky with a set, the few BMWs we have tried it on hasn't taken well.

The o2 simulators have worked as well, but after 100 miles or so of continuous driving it almost always would trip the light.

I wanted to say thanks to all those that have contributed and helped here for this solution.

I am familiar with the LC1 system, I have one tied into an HPTuners setup for my GM vehicles and GM engine swapped vehicles.

Genius solution, and honestly im very surprised there isnt more info about it floating around. Usually a good topic, a good fix; is plastered all over the internet. Over flowing amounts of info to get confused in. However with this solution I had seen a few threads that mentioned it, but only this one that actually details the how, and the why.

F1004fun, dpgrand, lkstaack (for your diagram), jonwrong and everyone else, your info has been invaluable and I thank you much for all the work you have put in.

F1004fun, what voltages are you running now, I see back in June you recommended trying some in the 700s, and under .050.. are you still going on those numbers?

This is my resistor setup. I used thermal epoxy to fasten the resistors to the aluminum which serves two purposes: mounting and cooling. I have been running this setup now for over 30,000 miles with zero problems.

Originally Posted by dpgrand

This is my resistor setup. I used thermal epoxy to fasten the resistors to the aluminum. The aluminum serves two purposes: mounting and cooling. I have been running this setup now for over 30,000 miles with zero problems.

whats the stats on those resistors? I was going to mount the o2 sensors up there.. but im thinking I could get the resistors working pretty easily as well.

Originally Posted by asb2106

whats the stats on those resistors? I was going to mount the o2 sensors up there.. but im thinking I could get the resistors working pretty easily as well.

I'm using 50ohm 10watt resistors

Originally Posted by dpgrand

I'm using 50ohm 10watt resistors

I'll be getting headers installed soon with the LC-1 right after. Did you use any thermal paste that's available? I'm wondering if there was a specific grade you used to make sure those resistors never come off. Which thermal epoxy in particular you use?

Originally Posted by daewon774

I'll be getting headers installed soon with the LC-1 right after. Did you use any thermal paste that's available? I'm wondering if there was a specific grade you used to make sure those resistors never come off. Which thermal epoxy in particular you use?

Arctic Silver Thermal Adhesive. "Thermal paste" is different.