Error code 27 - limp mode
 

So, I was driving my S5 GXL around today and suddenly I cannot rev it above 3K RPMs. I got it home as quick as possible and just now pulled that error code. My question is... what should I do now? Is it even worth it to buy a used MOP and put it in or should I run premix? The only thing about the latter is that I have been reading that there is no current way into "fooling" the ECU into seeing a functioning MOP. Opinions/suggestions appreciated...

go standalone, lol it dont care if you got a omp or not.

Used MOP's can be had pretty cheaply used (PM me, for example)... and you can't really remove your oil injection (on an S5) without going standalone. You'll need to get another, or it will stay in limp mode. Others should back me up on this.

Yes, I know that... but then I have to worry about it breaking again. I remember reading a thread a while back about someone trying to devise a method to "fool" the ECU. I have not seen much more since then.

hell haltec e6k is about the same cost as a new OMP from mazdatrix. have you checked those prices!! yeah but a used one shouldnt be to hard to come by. throw some premix in in the mean time if you have to drive it to stay safe.

Yeah, I checked that first thing and was like, "hell no." It does not need to be driven yet which is why I am trying to get suggestions now. I was thinking of just going premix all the way, but the car will still be in limp mode...

How does the car behave in limp mode? I just dropped a rebuild in and got a code 27.

I am still dealing with my code 27 problem. I had to replaced the OMP (used $50-$75) 3 times until I finally found one that met the specs (19-23 ohms). Some one else mention that it is not uncommond for the ECU to go as well. That is my next step. As for fooling the ECU, no one yet has been able to do it because of varying voltage at different RPM's. Several have attached the OPM in the engine bay and blocked off its original place and run premix.

The car behaves like you hit a brick wall when you are driving and try to get it above 3K RPMs. At idle it just will not rev that high at all. Lack of power, etc.