S5 OMP question/idea
01-02-08, 11:59 PM
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yessir
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S5 OMP question/idea
Has anyone found anyway to bypass the OMP for premixing with the stock computer?
Is there some possible way, besides going with an aftermarket EMS, to get that damned OMP out of my engine bay..
There's no odd loop lines, or anything you can do to trick the ECU into thinking it's there?
Is there some possible way, besides going with an aftermarket EMS, to get that damned OMP out of my engine bay..
There's no odd loop lines, or anything you can do to trick the ECU into thinking it's there?
01-03-08, 02:40 AM
#3
707
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rtek2.0?, yes you can block it off and leave it plugged in do a search a asked the same question a bit ago and it came up with a few good ideas
http://www.pocketlogger.com/index.ph...age=1&ecu=S5NA
http://www.pocketlogger.com/index.ph...age=1&ecu=S5NA
Last edited by Aaron Cake; 01-04-08 at 08:56 AM. Reason: Merge two posts
01-03-08, 02:59 AM
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Leah Dizon > Roast Beef
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It could be possible to replicate the omp electronic circuit or something but it's probably not worth the trouble when you can just leave it out of the way. If it's worth the trouble then you'll probably go standalone anyway.
01-03-08, 04:52 AM
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As long as it's still correctly connected to the ECU it can be located anywhere you want in/on the car. It doesn't have to be in the engine bay. Get creative.
01-03-08, 07:26 AM
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No, the ECU monitors the stepper motor position to ensure it's following the instructions sent to it. It must constantly see that the stepper motor is moving the way it's supposed to or it'll go into limp mode.
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01-03-08, 07:35 AM
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Supposedly you can put a resistor in there or something. However i have never met anybody who knew which one and where to put it. A buddy of mine had one jammed in there somewhere but it would only work like 15 minutes at a time then he would have to reset the ECU by switching the ignition off. He would do this while driving.... It was pretty ghetto.
01-03-08, 02:35 PM
#9
yessir
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but I was just wondering, if there was some stupid fast way to get rid of it completely.. i supose not, so i'll let it sit where it is hah...
damn that electric omp...
Also that rtek seems pretty nice with the mop removal...
I wish they'd hurry up and get on that S5 turbo ....
Last edited by Aaron Cake; 01-04-08 at 08:57 AM. Reason: Merge two posts
01-03-08, 02:44 PM
#10
I was also wondering about this...
Sure you can leave it to the side...but with the amount of knowledge around here you'd think someone would be able to make a circuit to plug in to the metering pump harness plug to replicate the varying resistance (I presume) of the stepper motor relative to throttle position (I think that's what it is). Something like that could retail for what, $20 to 40 bucks, and make some money.
P.S. I'm not that someone, but remember someone talking about making something like this.
Sure you can leave it to the side...but with the amount of knowledge around here you'd think someone would be able to make a circuit to plug in to the metering pump harness plug to replicate the varying resistance (I presume) of the stepper motor relative to throttle position (I think that's what it is). Something like that could retail for what, $20 to 40 bucks, and make some money.
P.S. I'm not that someone, but remember someone talking about making something like this.
01-03-08, 02:56 PM
#11
I took pheonix7's advice, "give up and go megasquirt"
In theory you could place a resistor in line w/ the ECU that would replicate the OMP and the position sensor, but you would have to replicate EVERY variance that is created throughout the RPM range under various loads and driving conditions. Just block it off and leave it plugged in.
In theory you could place a resistor in line w/ the ECU that would replicate the OMP and the position sensor, but you would have to replicate EVERY variance that is created throughout the RPM range under various loads and driving conditions. Just block it off and leave it plugged in.
01-03-08, 09:22 PM
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No, that's never been possible. If it were that easy do you think this thread and the dozens of similar ones would exist?
The electric OMP has been around for nearly 20 years, and in that time nobody in the whole world has come up with something like that. What does that tell you? If it were easy it would've been done by now.
Since it's obviously not easy, it's highly unlikely that the cost of developing it would allow them to be sold for $20-40 if the developer wants some money back to justify the time spent. And we all know how notorious FC owners are for indicating high demand for a product before it's available, but not when it is available. Sad but true.
Sure you can leave it to the side...but with the amount of knowledge around here you'd think someone would be able to make a circuit to plug in to the metering pump harness plug to replicate the varying resistance (I presume) of the stepper motor relative to throttle position (I think that's what it is). Something like that could retail for what, $20 to 40 bucks, and make some money.
Since it's obviously not easy, it's highly unlikely that the cost of developing it would allow them to be sold for $20-40 if the developer wants some money back to justify the time spent. And we all know how notorious FC owners are for indicating high demand for a product before it's available, but not when it is available. Sad but true.
01-04-08, 05:10 AM
#13
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Right now my omp position sensor isn't working right. Although once the car was out of limp mode it would work perfectly fine even though I know there is something wrong with the omp. After about 10-15 minutes, sometimes 5 minutes, the limp mode would come back and I'd have to restart my car to keep limp mode off. Eventually, after an hour restarting the car, it wouldn't go out of limp mode. Anyways, don't worry people, I premix... and I'm onto fixing the problem.
01-04-08, 09:00 AM
#14
Engine, Not Motor
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It's actually pretty easy to do. I've been considering it for a long time but since I don't own an S5 and really have no desire to eliminate the metering oil pump I have not bothered.
For anyone who wants to do this and has electronics experience, it's easy. The metering oil pump is just a servo with a stepper motor. All you need to do is program a microcontroller to listen to the step signals from the ECU (standard 4 wire if I recall correctly) and output a voltage according to the "angle". It's linear.
For anyone who wants to do this and has electronics experience, it's easy. The metering oil pump is just a servo with a stepper motor. All you need to do is program a microcontroller to listen to the step signals from the ECU (standard 4 wire if I recall correctly) and output a voltage according to the "angle". It's linear.
05-06-08, 12:59 AM
#15
talking head
It's actually pretty easy to do. I've been considering it for a long time but since I don't own an S5 and really have no desire to eliminate the metering oil pump I have not bothered.
For anyone who wants to do this and has electronics experience, it's easy. The metering oil pump is just a servo with a stepper motor. All you need to do is program a microcontroller to listen to the step signals from the ECU (standard 4 wire if I recall correctly) and output a voltage according to the "angle". It's linear.
For anyone who wants to do this and has electronics experience, it's easy. The metering oil pump is just a servo with a stepper motor. All you need to do is program a microcontroller to listen to the step signals from the ECU (standard 4 wire if I recall correctly) and output a voltage according to the "angle". It's linear.
the logic is a little more complex than that, and includes a load modification, rather than only direct from the TPS output
the sensor at the EOMP is also a different resistance
Originally Posted by bumpstart
the vid was using pots that we set up to emulate the TPS and the half scale OPS
( oil pump position sender )
here it is all hooked up-
( the trim being operated here is for the speed of the process loop )
that's the real TPS and OPS and motor
the chip that is running as a row of darlingtons is a little overloaded in this example
as it was a beta test of the logic, and not really for the drivers
( was a always expecting to need to bring in more than 1 amp circuit )
so the real deal will have dedicated darlingtons and heat-sink, and this chip will merely drive them under minimal load
this example is direct relationship, TPS for OPS
but final example will have output modified by rpm and load as well
05-06-08, 02:20 AM
#16
Wouldn't it be great if someone could actually make a seperate controller just for the oil metering pump and injectors. I was always thinking of something like a 5th injector controller-for those who never heard of this it's kind of like a band-aid that people use to use a long time ago for people who turbo'd their car and couldn't afford real programs and new ecu's. You may have also seen them as water injector kits like the aquamist that has it's mf2 controller. Couldn't we use this with an appropriately sized inector for oil since it's variable and sprays accordingly to fuel injectors? I'm really sick of all this **** with the damned omp as I had this same problem with my FD, that is until they came out with ecu's with oil maps. Any insights?
05-06-08, 04:37 AM
#17
talking head
the full intention of the final result for the unit pictured
is to provide control for the E-OMP
- and while we have those inputs for its load maps converted to binary words
use them to provide a pulse width output for mazda idle speed BACv control
and also for micro-fuelling with auxiliary injectors
( or load based PW suit smart WI )
and chuck in a few digital pull to earths as well
( for fans etc )
the sort of device that does everything but control the ignition and main injectors
( so all those with microtech or primitive ECU can have cake an eat it too )
other intended uses include those with s4 FC requiring s5 motor implant
- so they can use their original ECU and wiring
( mods to injector harness for early FC )
and still have E-OMP operation
-no need for silly wasteful octane and environment killing premix PITA
the original need rose from needing to convert the s5 motor to s4 timing cover and OMP
( with resultant lever / TB arm issue and also cut shut for turbo drain with s5 turbo )
for my LPG only FC
( i can't premix that ! )
so the issue would never need to be breached with subsequent later engines
nothing but that trial unit so far
though me and my crime buddy have tested its logic operation
and could quickly build some robust units with only basic EOMP operation
is to provide control for the E-OMP
- and while we have those inputs for its load maps converted to binary words
use them to provide a pulse width output for mazda idle speed BACv control
and also for micro-fuelling with auxiliary injectors
( or load based PW suit smart WI )
and chuck in a few digital pull to earths as well
( for fans etc )
the sort of device that does everything but control the ignition and main injectors
( so all those with microtech or primitive ECU can have cake an eat it too )
other intended uses include those with s4 FC requiring s5 motor implant
- so they can use their original ECU and wiring
( mods to injector harness for early FC )
and still have E-OMP operation
-no need for silly wasteful octane and environment killing premix PITA
the original need rose from needing to convert the s5 motor to s4 timing cover and OMP
( with resultant lever / TB arm issue and also cut shut for turbo drain with s5 turbo )
for my LPG only FC
( i can't premix that ! )
so the issue would never need to be breached with subsequent later engines
nothing but that trial unit so far
though me and my crime buddy have tested its logic operation
and could quickly build some robust units with only basic EOMP operation
05-06-08, 08:44 AM
#18
Engine, Not Motor
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-command it to move a set number of steps
-check via it's pot to make sure it's moved
Maybe I'm missing something here, but emulating it should not be any more difficult then having the microcontroller of your choice emulate the output of the pot based on the number of "steps" the ECU tells the controller to "move".
Is it more complex then this? In what way?
05-06-08, 10:21 AM
#19
talking head
The metering oil pump is a servo. Regardless of the resistance of the pot, the ECU can only do two things with it:
-command it to move a set number of steps
-check via it's pot to make sure it's moved
Maybe I'm missing something here, but emulating it should not be any more difficult then having the micro-controller of your choice emulate the output of the pot based on the number of "steps" the ECU tells the controller to "move".
Is it more complex then this? In what way?
-command it to move a set number of steps
-check via it's pot to make sure it's moved
Maybe I'm missing something here, but emulating it should not be any more difficult then having the micro-controller of your choice emulate the output of the pot based on the number of "steps" the ECU tells the controller to "move".
Is it more complex then this? In what way?
set point ( TPS ) for process variable ( OPS )
also thinking the stepper controls via a known number of steps per worm winding for a calculated stroke length output
( it has a feedback loop for a reason )
in the s5 it does not do so, and certainly doesn't in the example made by my friend and I
with the aid of a few small mud maps from the net, you will see that the factory, and the good ECU makers like haltech and altronic
allow you to alter the setpoint given by the TPS by some margin + / -
with the load, either MAF ( s5 ) , map and revs calculated from true 3d look up table or simple load algorithm
- its plain all this is not simple voltage trimming / resistance circuit summing of analog circuits
the half scale output ( ohms ) of the OPS will hint heavily its no simple analog relationship
ours is a 1024 byte pic based binary word algorithm calculation
to make things as simple as i can, and save a few moments
i will quote me from the magical land of oz
the basic logic is all worked out so we can classify analog inputs to a binary word
( both the sensor at pump and TPS are not same scales )
and use that word in an algorithm that has its variables as the inputs for load
( in this example they are all effectively a 1 in that algorithm as the TPS is in direct scale )
and that spits out the SP ( set point )
to this the OPS ( oil pump sender ) will send its own resistance, converted to its own
binary word PV ( process variable )
( in doing so an algorithm adjusts the value to have the appropriate word of same scale with the SP )
and these words crunched in a simple algorithm that results in a positive or negative or equal result
IE
PV - SP =
( a little more complicated than that with real logic with loop speeds and motor speeds ETC )
- motor up, down and stop
( both the sensor at pump and TPS are not same scales )
and use that word in an algorithm that has its variables as the inputs for load
( in this example they are all effectively a 1 in that algorithm as the TPS is in direct scale )
and that spits out the SP ( set point )
to this the OPS ( oil pump sender ) will send its own resistance, converted to its own
binary word PV ( process variable )
( in doing so an algorithm adjusts the value to have the appropriate word of same scale with the SP )
and these words crunched in a simple algorithm that results in a positive or negative or equal result
IE
PV - SP =
( a little more complicated than that with real logic with loop speeds and motor speeds ETC )
- motor up, down and stop
05-10-08, 10:27 AM
#22
talking head
http://www.youtube.com/v/rBl-M5lke_Q
after much mulling over the issues
the answer to a ready made display jig
was solved with aussie inspiration, a nail, a screw , bailing wire and eraser
05-10-08, 10:40 AM
#23
Rotary Freak
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I came up with an idea a while back in this thread;
https://www.rx7club.com/showthread.p...ghlight=S5+OMP
Here is the my posts quoted;
Take a look. I have no S5 to play with so I can't see if it would actually work. Seems like it should though.
Also has a position sensor on it as well.
https://www.rx7club.com/showthread.p...ghlight=S5+OMP
Here is the my posts quoted;
im going to guess that you need to hot wire the full range sensor meaning have a fixed voltage to the full range TPS input at the ECU on pin 2G for possibly idle or 1/4 throttle. Then possibly figure out what the voltage is at pin 2A (omp position sensor) at idle or 1/4 throttle and use a voltage divider or adjustable pot to get the voltage at pin 2A where it should be at the specific throttle point ?
this way the ECU always thinks the omp is in the right position at a fixed throttle point. The full range TPS is only used for the OMP.
Just a guess. I wish I had a S5 to play with cause I have been wanting to try this forever.
this way the ECU always thinks the omp is in the right position at a fixed throttle point. The full range TPS is only used for the OMP.
Just a guess. I wish I had a S5 to play with cause I have been wanting to try this forever.
Originally Posted by Aaron Cake
I'm not talking about the ECU, I'm talking about the metering oil pump itself. It's nothing more then a servo.
Last edited by RotaMan99; 05-10-08 at 10:46 AM.
05-10-08, 10:54 AM
#24
Engine, Not Motor
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Of course it does, that's what makes it a servo.
If it didn't have a pot on it, then it would simply be a stepper motor and the ECU would have no way of knowing it's position.
There is confusion because this thread is talking about two different things. I am talking about making a device to simulate the metering oil pump to fool the ECU. It seems like the other poster is talking about making a device to run the electronic metering oil pump without the ECU (which I have no idea why someone would want to do...).
If it didn't have a pot on it, then it would simply be a stepper motor and the ECU would have no way of knowing it's position.
There is confusion because this thread is talking about two different things. I am talking about making a device to simulate the metering oil pump to fool the ECU. It seems like the other poster is talking about making a device to run the electronic metering oil pump without the ECU (which I have no idea why someone would want to do...).
05-10-08, 12:07 PM
#25
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It seems like the other poster is talking about making a device to run the electronic metering oil pump without the ECU (which I have no idea why someone would want to do...).
Then your still stuck with fooling the ECU.