Now the car runs like **** when it tries to build up boost.

Pulled into the gas station, turned it off, filled up gas, then started the car and now it won't hit an boost ... otherwise it backfires like crazy.

Limp mode maybe? Vaccum leak?

The vacuum the car is pulling is still the same as it was before the problem, exhaust smells like gas and not coolant, no problem starting the car up.

What am I looking at here ?

 

check your map sensor.

 

check boost gauge.. whats it doing? if its hitting 0 when you step on it its probably a boost leak.. it could also be a vacum leak or sensor

 

Yep. Sounds like you may have popped of a hose.

 

Is this an FC or FD? Everything in your sig says FC.

S4's can't go into limp mode. What do you have for engine managment? If anything.

 

May not be relevant but this happened to me in my truck and it ended up being my FPR going bad.

 

My guess its a intercooler hose either torn or blown off. If it was the map sensor vacuum hose blown off clean it would read 0 psi all the time and not the correct vaccum. The map sensor hose could also torn

 

Its limp mode if it back fires right as it comes out of vacuum and falls on its face. Pull the codes and find what the stock ecu doesnt like, fix the problem, reset the battery and enjoy.

 

I posted in the 3rd gen section right lol

Have a pettit unlimited

 

dj i think we talked about and solved this earlier. i ran the resistors for hte nonsequential which fixed it the first time.

guess ill jump the diagnostic box and pull codes again .. blah

 

All the resistors underneath the manifold look to be in good shape.
Well checked the hoses and all seem to be connected fine. I'm running nonsequential and no emmissions.

Pulled the following codes:

30 Split Air Bypass Solenoid open or short circuit

33 Port Air Bypass Solenoid open or short circuit

34 Idle Speed Control Solenoid open or short circuit

38 Accelerated Warmup System Solenoid open or short circuit

39 Releif 2 Solenoid open or short circuit

45 Charge control Solenoid open or short circuit

46 Charge Releif Solenoid open or short circuit

Probably something to do with code 39 ?

 

I would double check that all the resistors are still connected correctly. I had a car about 6 months back that would go into limp mode and wouldnt pull any codes that would cause limp mode. It had me stumped so I plugged in another OMP and that didnt fix the problem. Double checked all the resistors, that didnt fix it. Turned out being a faulty knock sensor but when I pulled the codes it didnt pull the code for the knock sensor.

 

i think it could definately be a knock sensor problem. having a freind come over to help diagnose it later