WoodManZ

Just like it says. I know it can be done but I've searched and can't find a schematic. Any help would be greatly appreciated.

Bill Bowling

iTrader: (6)

I think most people here just turn them off using HPTuner or EFILive FlashScan.

Bill

madcrazy

try soldering a piece of wire or paper clip to the fork (two prongs on the recieving side of the line) test first though...i kno it works on many other sensors. to test stick paper clip in so that it will temporarily stay in and touch both sides then run your car several cycles make sure it responds ok.

RelentleZ

iTrader: (4)

if you dont use O2 sims will the check engine light just come on or will the engine actually really act up?

foff667

iTrader: (2)

na, just the check engine light...the rear sensors are basically just a check to make sure your cats are functioning properly.

RelentleZ

iTrader: (4)

so pretty much the only reason i would want to spend 90 dollars on O2 sims is if i want the check engine light to go out. im glad i found this out. almost bought em.

jimmyblue

iTrader: (11)

I had a pair sitting in my "box of odd little engine
parts" and the mechanic found them and put them
on, during the header install. I have the codes
turned off already. They are a swell way of keeping
grime out of the harness connectors But I will
try and find a couple of dead O2s and cut off the
ends, so I can clean the sims up and sell them
some day.

618HAWK

iTrader: (361)

Don't the sims incorporate resistors just for the pcm to see that there is something there. Ie for the o2 sensing portion and the heater.???? Looking for either a open or a short upon start up.

dlmater

iTrader: (7)

Actually, the PCM is looking for a varying voltage signal from the rear O2's. A resistive load only will still set codes. The PCM looks at the rear O2 signal and compares it to the front O2's to gauge the operating efficiency of the cats. Thus, a signal must be present for the rears to prevent code setting.

As mentioned earlier, the easiest method is to turn off the codes. However, the link below shows a schematic for producing a varying signal (sine wave type) in the proper voltage range and frequency to simulate an operating cat.

I have found some generic O2 simulators on EBAY for very cheap (cheaper than you can buy all the components and necessary parts to mount a homemade sim) that do work great. However, you do have to splice into the O2 harness to install. Check the For Sale Section here as well.

http://www.mkiv.com/techarticles/oxy...sor_simulator/