Ok, so my engine is throwing code 30, which is the split air solenoid valve. The light only comes on under acceleration, if I let off the gas it turns off. I also intermittently get a 27: OMP. This is pretty rare though, and hasn't happened for more than a month. We know the alternator is likely on it's way out. On test it got only 13.2ish, which is well below spec. Not really a surprise the thing's likely 16 years old..

ANYWAYS...the symptoms. Response is a joke, my acceleration has taken a hit. I haven't had a chance to look under the car yet. I've added a few grounds, and that has helped slightly. Is it possible that I have some loose/faulty wires down there by my OMP that causes the rare 27? WTF is a split air solenoid valve----before you flame me I searched, not much to find. Not to mention the FSM isn't very clear about it---and would it cause this kind of problem. And lastly, is the alternator the real culprit in my lack of acceleration? Answers to any/all of these greatly appreciated!

 

So I'm guessing everyone's as stumped as I am about this...or do I not explain it well enough?

 

im sorry but wtf is an OMP. i've seen this popping up a lot lately in messages and i dont know wut it is, sorry to be a noob about it.

 

It's ok. It's the Oil Metering Pump or Metering Oil Pump (same thing but goes by both names). It injects crankcase oil into your engine to keep everything lubed. It can be removed completely on S4's without any issues in favor of premix since the OMP is mechanical. On the S5's it can't be removed w/out a standalone, since there's a sensor attatched that will cause the engine to go into limp mode. It does this because in theory if your OMP isn't functioning you aren't getting any oil into the housings, so it prevents you from seizing your engine by not letting you have any power or acceleration. If you go into limp mode, you'll know.

Most people, regardless of S4 or S5 prefer premixing 2 stroke, since it actually burns and does not leave any ash deposits in the engine, as normal oil does. I hope this answers your question and a couple more

 

Does the engine lights start blinking and feels like your leaning out when your WOT before 4k rpm?

Do you have emissions removed?? If so you shouldent even have a split air selanoid valve.

 

That's sounds very similar, if not the same thing that happens to me. Yes my cat is removed, but no, my ACV is not. I didn't want to try to mess with another way to open my 5th and 6th ports.

 

So does anyone else have any other ideas?

 

Bump...someone's gotta know somethin...

 

Anybody!!

 

try a different ecu and if the problem still occurs?

 

bump....the problem isn't the ECU...been that route

 

Ok, so I got my S5 alt rebuilt, and the car runs much much better. No check engine lights at all! I do have one issue, however....if I'm idling and rev the engine slightly, the lights get brighter. Note that I don't have a system, e-fan, or anything that should be a major drain on a healthy alt/batt. Is this likely a wiring issue? That's my first guess...but I wanna see what all you experts out there think hahaha