S4 TII Studder under full throttle
 

It isn't the normal secondary injector ground problem. When he gets on it it studders and makes a rev limiter type of sound but goes away and then a few seconds later it will happen again. It has dissapeared after he has cleaned his fuel filter but then comes back shortly after. Does anybody have any words of advice for me? :Wconfused
Thank You

can it go past a certain rpm like does it kinda hit a wall at like 5k rpm

Just had a similar issue. My suggestion is to borrow a CAS from a friend and swap it out and see if it cures the problem. Can he accelerate through with lightly touching the gas?

Hope that helps.

Man mine just started cutting out on me too. I can accelerate lightly but that's it.

You need to provide more info. Does the car free rev while idling or does the same problem persist.

Yes free rev while idle. When I put a load on it it hesitates with an engine light. On off key and back to normal with light throttle

You need to check for codes as perhaps you're having problems w/the OMP.

Please explain more on possible omp issues?

If you have problems related to the OMP the car will operate under a type of safe mode which prevents the car from being driven hard under load. Turning the key off and then restarting the engine gives you possibly a little time until the ECU goes back into safe mode. You have a Green check connector near the leading coil w/a single Orange wire. Ground this wire and w/key to on the error codes will be displayed.

http://www.banzai-racing.com/FD&S5_error_codes.htm

Got a 25 2 long 5short.

Buzzing? Where is the buzzing coming from? maybe the back of the cockpit? What are you using to clean the fuel filter?

Last I remember, my buzzer was nicknamed the red light of death.

So a code 25 is for the Pressure Regulator Control Valve. At pin 3M of the ECU, which is Blue/Orange wire, and w/key to on it should read less than 2 volts. When starting a warmed engine the reading is below 2 volts while cranking, and below 2 volts for the first 20 seconds of idle during a hot start. After 90 seconds of idle the voltage reading is 12 volts. This valve is used to increase fuel flow under certain situations. When the voltage is low is when the valve is increasing the fuel flow. When the voltage reading is high the valve is not adding more fuel.

I have my rats nest removed. Where is the prcv?

Then that's why you have the code although if the nest is removed then you should have more codes.

It probally does but just odd it ran fine than started hesitating within the last week.