Hey everyone,

I'm trying to find a sensor, It's the black OMP sensor. I believe it's a position sensor. I went to the parts department at Mazda and they said it isn't sold separately.

I was wondering if anyone knows where I can buy one or has one for sale?

I've contacted Paul @ Mazmart and Rob @ Pineapple Racing, Neither have anything.

Hope someone can help me out.

Thanks everyone,
Jeremy

 

Have you tried your local salvage yards?

 

Yea, Not a single one has an RX8. A few RX7s but they have different OMPs.

Right now I'm looking at beck arnley throttle position sensors because I believe they are the same sensor. It could also possibly be a mikuni just trying to do some research.

If anyone has a local salvage yard that they check out or know an RX8 is there I'd be more than willing to shoot some cash your way to retrieve this for me lol.

Thanks again everyone,
Jeremy

 

This is what I found so far

http://www.rockauto.com/catalog/moreinfo.php?pk=936401

Appears to be the same position sensor they used, however the connector isn't going to work properly. I would have to cut the connector off the throttle body of an Mitsu outlander and then splice it in once I determine which wire does what.

Anyone have any thoughts?

 

Sure does look like it lol.

These might help you...

 

Yea, I've been looking at the harness and the connector trying to compare it to the manual. See how bad my connector really is.

Hopefully someone knows of an 8 in the junk yard or has a parts car around.

 

Jeremy did you solved the problem with the throttle position sensor? My OMP sensor just broke and I need to know if you were able to fix it with that part you find in rockauto.

 

This appears to be a direct replacement.
Throttle Position Sensor TPS Suzuki Chevy 91175256 New | eBay

Hope it helps.

 

Might be worth the $11.50 to try it out..... ;-)

 

Is the same but the screw holes are a little offset, and doesn't go all the way inside the pump.

 

Does anyone know if this worked or not? With it not going all the way inside will it leak oil around it or anything?

 

It won't leak any oil....that shaft is sealed. The issue is will it fit and do what it needs to do to give the ECU the correct signal

I would look for a used OMP....and be super careful that you install the pump after you put the block back in the car

 

A throttle position sensor won't work. It was mistakenly claimed to be a TPS off the Mazda KL engine because they have a similar shape. Later somebody actually tested it and others have since verified. It's a rotary on/off switch. Once it rotates to approx 70 degrees it changes from an open to a closed circuit. I tried a bunch and never found anything. Unless you can get to the OEM source and convince them to sell them publicly then your only option is used. The pump is made by Mikuni and they also are a big supplier of rotary style TPS etc. switches so in all liklihood they are the source. A few people tried contacting them and didn't get too far.

 

It's not just an on/off switch. It's a rotary encoder that also happens to go open circuit when it's beyond it's limit. If you look at it with just a multimeter it's easy to make the mistake, but looking at what it feeds the ecu with an oscilloscope tells the whole story. It sends pulses to the ecu as the OMP throttles for more flow and for less flow, these pulses are counted and directly correspond to the OMP map. For this reason it also doesn't matter how you install it so long as the ECU gets enough pulses before it goes open circuit.

 

I consider member "Delmeister" the authority on the subject. He's posted extensive testing on the subject so feel free to make your assertion with him.

 

Thanks for pointing me in the right direction. I found this threadhttps://www.rx8club.com/series-i-major-horsepower-upgrades-93/mop-adjustments-120276/

And you're right the ECU seems to only use the switch to make sure the omp moves, and there is actual Mazda documentation to prove that. I still don't believe the "switch" itself is just a switch. All the switches I've ever used have a constant resistance when closed, and a constant resistance (or infinity) when open but this one doesn't, and it doesn't act like a pot either, well not exactly. Can't find my spare or I'd post data. With enough searching it should be possible to find a replacement, because if the part is not just a specialized switch for us then it must used in other applications.

This does make it fairly easy to spoof an omp electronically. Just read the stepper inputs and then trigger the signal within the acceptance range.