Limp mode with no OMP
 

CAn anyone confirm, as in actually tested if ECU goes into limp mode with NO OMP attached? More specifically, will the TB butterfly stop opening with key in ON position?

I'm using the 20b omp attached to aftermarket ECU, so I don't have the rx8 omp attached, but I'm positive I had butterfly movement up till about a week ago.

It's a 20b conversion, obviously btw.

With the stock ECU you will be in limp mode. It will work for about 6 sec after a reset..and then stop responding more than a small amount

What ECU are you using?

Personally..save yourself the grief and run a proper throttle cable ;)

Cool man thanks. I hooked it up and still no joy! FK me!

TB is def getting power, can hear it but no movement. Grrrr. I don't have rear O2 sensor hooked up but pretty sure that won't do it.

Using a dedicated LPG ECU called profire, I don't recommend it as the business owner is a total dick. Never gave the relevant diagrams, just generic shiz for other applications. Wishing I had used adapt or haltech now. She's booked in with my local LPG guy on Monday for the certification and hopefully for starting and tuning, but not unless I get the TB working. Grrr

Yeh thinking bout wacking on the 20b TB, STILL GONNA BE A MISSION TO complete BEFORE Monday THO, ITs Sunday here now.

After Doing the RX-8 DBW TB..and going to the REW manual throttle I would never go back

Did u ever get the dbw working?

It worked fine....but it has some issues. Especially when you remove the MAF and try and push 4x the air through it. It would seem to partly close sometimes and even adjusting the scale for the pedal it always felt laggy. Not sure how to explain it.

Do you have the ECT sensor hooked up? I think you need that one too 😊

Yeh temp sensor is plugged in and working. Got me stumped, u got me worried now bout the dbw. Better change it I think. What's the easiest pedal - cable combo u have seen/discovered/used?

Actually, just for now I think I'll convert the dbw TB to cable, just so I don't have to make an adaptor pipe to suit my layout, ain't got time for that. Just need to get it working before tomoz.

I used Lokar stuff and made a bracket to hold the pedal. Wasn't super easy.

I have seen the stock pedal modified to use a cable too. Not sure the specifics on that though.

I wonder if it's possible to use the pedal to control the dbw without the ECU, like bypass ECU somehow. A bit like a servo in remote control cars

Better make sure you write good code...I'd hate to have a runaway throttle...or one that decides not to work at the wrong time 😕

Horry shrit!!!

I just tested my running car, each wires power while running and making pedal changes, omg! I'm even more clueless than before.

I need a pedal with a resister type contact set up to adjust the voltage. Not sure if the TB motor can be variable voltage tho. Ie 1v opens a touch, 2v more 3v etc.
I tested it with 5v and it still opens fully, tho it takes longer to do than at 12v. Damn, where am I gonna find 1v

So need to bypass this ecu

It's more complicated than that. ...there are 2 circuits that have different voltage profiles. I think they are inverted if I remember correctly. ( might just be different scales...?? ) The ECU interprets them and looks at the position tables and then opens the throttle plate.

Ask Brettus....he will know a lot more than I remember. It has been 3 or 4 years since I ditched the DBW

Hey danobre, do u know what the vac nipple under Tb is for? Vac ref for idle sol?

Sin, Are you talking about the VAC nipple on the UIM behind the TB?


Travis

https://cimg0.ibsrv.net/gimg/www.rx8...353e4a9cff.jpg

It goes to the VFAD valve on the intake. A lot remove the VFAD assembly and then cap off the Vac nipple

Sorry guys, I meant on the 20b TB