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trying to use op-amp summing circuit to offset car sensor voltage

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elRey

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I have no electronic design knowledge, so plz forgive my ignorance.

I want to offset a signal voltage coming from a car sensor being sent to
the car's ECU. The sensor in question is the O2 sensor.

The ECU sends a +5v reference to the sensor. The sensor then returns
a +.2v to +4v signal back. It's usually about +1.5v and jumps back and forth
around this value.

I want to offset this signal +1.5v. If the O2 reads 1.45v, I want the ECU to see 2.95v.

I search and found this circuit:
https://www.electro-tech-online.com/attachments/adder1-gif.440/

And tried recreating it on my "300 in One Electronic Project Lab" breadboard.

But I can't get it to read the expected voltage with a multimeter.

I'll post a wiring diagram in a minute to show what I have.

Thanks,
Rey
 
What possible reason could you have to want to do this?
It'll just confuse the computer and make the engine run like crap.

Your op amp may be able to put out more voltage than the original O2 sensor was capable of, and thus may be higher than the ECU can take which could damage your computer.
 
This will only be used when the secondary air injection (smog) pump is used.

A way to remove the pump, but make the ECU still read the change from the
O2 sensor when the pump should be running.
 
You are trying to fool your car's computer so it makes more smog??
Just to go a little faster??
Doesn't it burn more expensive gas that way??
 
Only purpose is to be able to remove smog pump without car throwing any
fault codes and making Check Engine Light come on. This pump ONLY
runs on cold start-up. Also, without the pump, it fails a SAI emission
readiness which also stores a code.

The pumps only purpose is to heat teh CAT faster on cold starts so it
can reduce emissions. The faster the CAT can heat up to operating temp, the faster
it can start reducing emissions.

Not for power.
Doesn't run for more than a minute a day.
 
Sorry, but there are many teenagers running around in my city with the catalytic converter and muffler on their cars removed. The cars are new but their pollution can be smelled far away.
What's wrong with your smog pump?
 
I'm not removing my CAT or muffler, nor am I a teenager.
The difference in pollution would be about 30sec once a day when
I start my car for the first time. After that 30sec, my car will not produce
anymore emissions than with the pump.

Is this a car forum? Environmental forum?

For once, I decide to give a little more information up front than needed to
get an answer in hopes I don't have to later explain myself. A lot of good that does.

All I'm asking is why does the breadboard I wired not provide the expected result.
And does it follow the circuit (different volt and resistors) in 1st post?
If not, what did I do wrong.
 
sir i have power amp design with 12 volt dc with transistor 2n3055
please give me dishcraption how is posible.thanks
 
elRey

I think you should pull R6. Also I would run pin 11 direct to ground.

AllVol
 
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