Can we talk about something illegal?

I have a tuned ECU on my 240sx and the tuner "turned off" all the MIL software. Of course it's tuned to a point where it won't pass the sniffer.

When smog time comes I replace it with a stock ECU though. I have put a resistor in place of the EGR temp sensor so I'll never get an EGR code. With a mild cam, a high flow cat, and all emission equipment disconnected I can still pass...barely. I just make sure I run 91, retard timing to minimum specs, and run a colder range plug. Since my NOx is good but my HC is high I might try the hotter plugs and see if that gives me a little more wiggle room.

Now this is on an OBDI car, but I am sure a good ECU tuner can do the same for an OBDII. Have one map for performance and one map for smog.

*Note to self: Don't move. What a berkeleying racket. Please sell all your emissions failing, perfectly running cars to ME!!!

In reply to poopshovel:

Dude, you are close enough to Atlanta to buy people's failing cars.

curtis73 wrote: I do my best to buy exempt vehicles. Here in TX that means diesel or pre-88 (I think). In CA its diesel or pre-76 (I think). I had many of the monitors voided on my OBD2 and it won't pop the CEL on for nearly anything. The rotor broke in my distributor and the car would barely run, coughing and sputtering, backfiring. I limped it home for 1 mile and it never tripped the light. But... its also a bit frustrating since I didn't have any codes to narrow down my diagnosis.

Texas is a rolling 25 year test. If its older than 25 then it gets a free pass. Kinda like an old lady that swears like a sailor and everyone let's her get away with it because she's old.

Not sure if this would work on OBD2, but on my OBD1 Supercoupe, I actually have a dial switch loaded with multiple tunes connected to the stock computer. I have one tune I use only for passing the tailpipe sniffer test. Changing tunes is as simple as opening the glove box and turning a dial. Holds up to 7 tunes, works on the fly.

Giant Purple Snorklewacker wrote: Instead of a dead port... why not get an ECU from something OBDII and well understood and fake the inputs? Think of an MS "stim" only a bit more active to provide a nice clean 800 RPM steady state to the ECU with good values for the temp/o2/etc... then just stuff it under the dash and leave the port handy when you need it? It would probably be unethical to form a small business selling "cheater boxes" but if you call them testing harnesses they are perfectly fine

My latest project is an OBD 2 car, and we now have the plug in tests. We did consider using a MS and running the stock ECU with resistors (a diode on the MAP) on the sensor inputs, and injector harness but figured it would just be easier to use an old MS1 as an EIC, keep the good drivability of the stock ECU and clear the MAP code at test time.

The guy who reflashed the Motronic ECU in my 850 Turbo just asked me if there were any CEL codes that I wanted the computer to ignore or stop showing.

I had him drop the EGR flow and the 2nd o2 sensor.

Shawn

poopshovel wrote: *Note to self: Don't move. What a berkeleying racket. Please sell all your emissions failing, perfectly running cars to ME!!!

If it fails emissions, it's not running perfectly, is it?

alfadriver wrote: Forgive me for asking, but why? The way you posted your note, you want to intentionally pollute. You really want to modify your car to make more power right? Or do you just want to dump your garbage on your neighbors lawns?

While my reference isn't pertaining to obd-2, because some manufacturers allow retards to design catalyst systems......I'm sorry, but the ford engineer that designed the rear bank catalyst on the gen1-2 sho's deserves to be flogged......90* into the top of a catalyst....come on ford.

That said, Casper Electronics does make o2 sensor emulators that are meant to prevent CEL from running no-catalyst on an obd2 vehicle.

pfr wrote: In reply to alex: Here in Canada we have got the new emmission testing procedure, same as the US. It is a f*#king nightmare for us used car dealers. It's adding hundreds of dollars worth of time & repairs to some vehicles, the cost of which can't be recovered. A 'cheater' adapter that tells the testing equip. that all systems are good, would be good. To ALFADRIVER, the US has been polluting this part of Canada (Ontario) from the Ohio Valley for years, so don't mention "dumping you garbage in your neigbours yard" to us!

sounds like until now, you canucks are the ones who were polluting my part of ohio.

plus you guys do silly stuff like spell neighbors with a u.

xd wrote: I Think This is What You Want There is a program for android phones called torque. It connects with a blue tooth ODB adapter that runs about 30 bux. You can clear all the codes out you want with it. It's fun.

Sure, you can make the little light turn off, but when they plug it in, their computer says, "Hey, the O2 downstream test isn't done. FAIL."

Move to Michigan or similar car friendly state where nobody, not even the cops, cares. I've never had a car that didnt spend a month or more with no muffler. I sold the cat of my Yugo for glasspack money, the only muffler on the car(you have to wear earplugs on the highway). The rats nest of vacuum lines are in a box in my basement, evap is a hose hanging in the engine bay. It doesn't even have a working blend door on the air cleaner!

Wait a minute, Alex. Do you actually have cars that run OBDII?!

curtis73 wrote: I do my best to buy exempt vehicles. Here in TX that means diesel or pre-88 (I think). In CA its diesel or pre-76 (I think).

I hear they're testing diesels out here now and the smog place by my gym has a banner advertising that they can test diesels there.

Also auto stores no longer read CEL codes any longer due to CA regulation put in place a couple years back.

I heard that IS guys, when installing a header would throw a B1S2 code and instead of getting an o2 sim, would go into the ecu junction box and splice into the B1S1 signal. Now the car would not trip any codes and would have the car in system ready status. On the sniffer it will fail. I also heard, for some reason, some genius (ahem) had a brain fart and did this when his car needed smog, even though he had put the car back to stock with a new o2 sensor in hand ready to install. Of course he was at one of the ruder shops in town who was amazed that the car passed the readiness code reader but failed the sniffer and kept going on about never seeing that in all his years. He then promptly flagged the car as "tampered" so that particular car needs to be smogged more often than others. It's passed with flying colors every time since though. So I've heard.

DuctTape&Bondo wrote: I heard that IS guys, when installing a header would throw a B1S2 code and instead of getting an o2 sim, would go into the ecu junction box and splice into the B1S1 signal. Now the car would not trip any codes and would have the car in system ready status.

That should flag a P0420 in very short order. They monitor the catalyst by checking the switching speed of the front O2 vs. the rear O2 - if they switch at the same rate then the catalyst isn't doing anything.

I don't know of a way to trick the computer at the inspection station, but there is always an easy way to trick old computers into thinking everything is ok... ie, if 02 sensor is failing, find out what range a healthy one measures, if its voltage/resistance/whatever, and wire in a resistor in the sensor's place.

every sensor tells the computer what its measuring in some format, typically voltage or resistance. these things are easy to fake.

Of course, the newer the car the harder this is to do. never tried on on new stuff... what exactly does the 02 simulator do anyway? will the ecu throw check engine if it sees a steady state from 02's?

N Sperlo wrote: Wait a minute, Alex. Do you actually have cars that run OBDII?!

Heh. Only one remains. Sold the Miata and the SVT Focus to no-emissions-test states. Only the ZX3 is OBDII, and that's staying unmolested.

I'm resigned to just making any future play cars pre-'95. Or I may get a rural PO box.

andrave wrote: will the ecu throw check engine if it sees a steady state from 02's?

Yep.

Not switching quickly enough, not switching often enough, staying too low, staying too high, excessive warmup time... there are probably 20 different ways that they test the sensors' response.

These aren't old L-jet computers that operate on the "don't know don't care" school of fault tolerance. Probably 80-90% of the computer's power is spent on fault checking, not actually running the engine.

I can't fathom why you'd WANT to fake a sensor output like that, anyway. It would just make the car run horrible.

BoostedBrandon wrote: REGISTER somewhere that does no testing. /problemsolved

FTFY

Zombie thread, canoe deleted.

Zombie it may be, but it's interesting.

Taiden wrote: What you are looking for is an OBD2 port simulator. It essentially handles all requests from an OBD2 code reader, and reports that everything is kosher. These are incredibly illegal, and everyone in the history of mankind to sell them openly has received a firm cease and desist letter from the EPA. Someone was selling one for people who prototype OBD2 readers, and he was shut down very quickly. Although, anyone who is familiar with serial data and embedded systems should be able to churn out a couple basic ones pretty quickly. But I'm certain the people who do keep it very, very, very, VERY quiet.

This is what I think the original question was as well. A complete OBD-II fake box. I understand how there would be a market, and I totally understand why the feds would land on anyone making one like a ton of bricks.

On our LS conversions, we can turn off various monitors if we want. Heck, the standard swap kit electronics doesn't even include the secondary O2 sensors to monitor the cats or have the ability in the software. When you try to read the codes, it just says something like "N/A" for those sensors. For some (many) states, that's good enough. For others, it's not. For those states, we have to use the E-ROD kits that include more emissions monitoring capabilities. We put cats on all the cars anyhow so it doesn't make any difference to the actual emissions levels, but you're more likely to get a smile at the emissions testing station with those extra monitors in place.

You guys are doing it wrong. What you need is simple deception, not a technical approach.

Put a plate from a different state on the front even if your state does not require one. Scrape off all inspection stickers. Put an FOP sticker at that location.

Profit.

Timely bump for me. We have a vehicle that runs and drives, and will probably be reliable transportation for about another year. It is worth about $900. We can't get it to pass emissions. It isn't worth it to pay the $500 it is going to take to either get it to pass or get the exemption. Pisses me off.

Probably going to sell it to Carmax or downstate where they don't test.

In reply to mtn:

I'm still very thankful to live in the land of not having to berkeley with it.

The way I see it, emissions testing is Federally mandated in areas that fail to meet clean-air standards. Areas that fail clean-air standards do so because they have a lot of industry and business and people moving around.

So having to pass emissions is a side effect of living in an area prosperous enough. Or living in a prosperous area has emissions testing as one of the things that just comes with the territory.