Ever since I blocked off the ACV my car has run like absolute garbage. I have looked through every thread, youtube video, and write up on the topic. I kept my thermowax and BAC but blocked off the ACV and EGR. I did the acv and egr on separate days and the car started running bad specifically when I deleted the ACV and air pump. I deleted the rats nest, purge valve, and all solenoids. I bypassed the FPR vac line to the intake and ran a fresh line for the primary injector air bleeds to the dynamic chamber. I ran new fuel injection-rated hose to the rails (and yes I verified 100 times, its all hooked up correct) I capped the holes on the air box for the air pump. The split air pipe is still there but runs to nothing and has already been cut by PO since the car has a straight pipe on it (no cat). My dashpot checkvalve broke so I just have a hose running to the thermowax with no valve, was planning on putting an auto zone 1 way valve on there once I got the car to run. I doubt that lack of check valve is causing the car to run like this, it has no power. In its current condition it can start with the key but has trouble doing so I've had to pull start a couple times. I've cleaned my plugs multiple times and they're new plugs.

To reiterate: the car started running like **** as soon as I pulled the ACV and blocked it off. I even had the air pump on there disconnected for a bit and the car still ran great but when I pulled the ACV and blocked it off is when it started running horribly. Any tips or new things to check would be greatly appreciated.

 

Have you apply some sort of gasket/sealant when you install the block off plates. Lack of power can be from your 5th and 6 port not opening because it runs off the back pressure of the exhaust via split air pipe, if you wire them fully open, you lose low end torque. Not sure what you meant about your fuel pressure regulator, vac line from FPR to intake.

 

i agree with TerryD ... if you pinpointed the behavior you described to when you removed the ACV, then i would hold the seal at the block-off plate suspect.

 

I vote for vacuum leak at the ACV blockoff plate.

 

All in favor of no gasket at the ACV say Aye

 

I think I found the issue ! Got some kind of fuel leak under the car, had some in my driveway today. Makes sense bc it felt like fuel and I know I did everything correctly for the delete.

Also by vac line to fpr I meant: There is a vacuum line coming off the fuel pressure regulator that when stock, runs to a solenoid before running to the dynamic chamber. In certain hot start conditions the solenoid will open and have the FPR run off atmospheric pressure instead of intake vacuum. Deleting the emissions nest and said solenoid requires you to now bypass said solenoid’s vacuum line to the dynamic chamber for the fpr. Other solenoids are all acv related. At least on an na s4.


Here’s hoping its not my pulsation damper!