Author Topic: O2 sensor simulator.  (Read 8117 times)

Offline Whodatjrock

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O2 sensor simulator.
« on: April 13, 2010, 04:22:49 PM »
Ok, I saw a post about after cat sensors. My question is, the o2 sensor that was connected to my exhaust manifold is just sitting by my valve cover. My check engine light comes on after about 5 minutes of driving. My gas mileage is horrible after the headers were put on. What kind of simulator do I need or can I just remove the whole sensor. I seen a couple of simulators but have no idea which I need. I have a 87 silverado w/ 5.7 350 tbi. I have no cats.

Offline VileZambonie

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Re: O2 sensor simulator.
« Reply #1 on: April 13, 2010, 04:30:34 PM »
The post Cat O2 simulator was what we were talking about. If you have a tbi system you need to hook up the O2 sensor. Just get a bung and put the sensor back in. You can get an O2 bung for less than $4.00
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Offline Layne

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Re: O2 sensor simulator.
« Reply #2 on: April 13, 2010, 06:02:04 PM »
*Curious* Why is the O2 in the drivers side bank, as opposed to the 88-98's is after the Y pipe? Would the passenger bank run EXACTLY the same as the left?
77 c-10 - 77 400 86 700r4 "Emmy"
83 citation - 2.5L Four on the Floor!
88 sierra - reman 350 700r4 "Eleanor"
All normal practicality and rational money handling goes out of the window when it comes to my truck.

Offline Irish_Alley

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Re: O2 sensor simulator.
« Reply #3 on: April 13, 2010, 06:13:14 PM »
I would assume it would be cause of the efi since each injector goes to each cylinder while your truck if it has a tbi its only two injectors
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Offline Blue 82

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Re: O2 sensor simulator.
« Reply #4 on: April 13, 2010, 06:32:16 PM »
The 88 and 89's are mounted on the drivers side manifold
My 94 has a 3 wire after the "y"
My 2000 5.7 has 4.
When I put shorty headers on my 89, I get an erratic O2 voltage reading at idle and around town but I get a decent voltage reading on the highway. Due to the mods I have done, it's running lean at anything over 30% throttle (but that's another story).
I'm guessing the O2 sensor is not getting hot enough at low speeds/load.
I have a spare 3 wire (heated) O2 sensor from my 94 that I'm going to install in the 89.
I just need to find a factory style connector to make it happen.

You can mount the O2 sensor after the Y, just extend the wire.





82 stepside 2wd 355/th350/3.08 posi

Offline Layne

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Re: O2 sensor simulator.
« Reply #5 on: April 13, 2010, 07:16:24 PM »
I have these- http://www.jegs.com/i/Flowtech/387/91830/10002/-1
Just curious. Thanks guys.
77 c-10 - 77 400 86 700r4 "Emmy"
83 citation - 2.5L Four on the Floor!
88 sierra - reman 350 700r4 "Eleanor"
All normal practicality and rational money handling goes out of the window when it comes to my truck.

Offline VileZambonie

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Re: O2 sensor simulator.
« Reply #6 on: April 13, 2010, 07:28:48 PM »
Irish is correct. The O2 is only valid if everything is working correctly. Being a dual plane TBI system it would read the same. The O2 sensor isn't designed to compensate for errors and is only efficient if the engine is operating as designed.

Zirconia O2 sensors need about 600°F to wake up and start functioning hence why they put them as close to the engine as possible.

On my Mutt I welded a bung in the Header reducer. If anyone wants to see pics I'd be happy to take them.
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Offline Whodatjrock

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Re: O2 sensor simulator.
« Reply #7 on: April 13, 2010, 08:16:21 PM »
Thanks, I have ceramic coated headers. Should I put a hole in the headers or can I extend the wires and put the bung on the pipes?

Offline VileZambonie

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Re: O2 sensor simulator.
« Reply #8 on: April 14, 2010, 07:25:56 AM »
Put it in the reducer
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