aeromotive fpr vacum line leave attach or detach?

[Drift King]

I have just recently installed my aeromotive fpr into my car, my maine concern is that whether i should keep the vacum line plug back into the fpr or not, if i do not put the vacum line back in, my car however will hold boost pressure more and gain my power, if i pluged the vacum line back in, my car will not hold alot of boost pressure, it will infact i believe spike, because every time i try going WOT on it, i only make it about 25% of WOT and never really fully reach 100% WOT and my boost gauge will go up so fast that i hit fuel cut. So i debating whether I should keep the vacum line that attached to my fpr in or leave it off.

Before installing the aeromotive fpr, i still could never be able to hold boost steadily, even if i tinker with the boost controller, it still wont hold constant boost pressure. Any suggestion on that as well as the vac question.

 

[TunaTalon]

The vacuum line to the AFPR is absolutely necessary. Without the vacuum/boost line the fuel pressure will not increase with boost. The 1:1 fuel pressure increase keeps a constant differential pressure across the injectors so that the length of the pulse to the injector reliably controls the amount of fuel delivered.

Without the vacuum line the mixture will be lean at boost leading to knock and possibly detonation.

Leave the line on.

 

[NB4G63T]

Check for boost leaks. Thats proly why you can't hold boost and as already said, do NOT unplug the vacuum\boost line to the afpr.

 

[snowborder714]

The only time the vacuum line should be disconnected is when you're setting fuel pressure.

I would also recommend getting rid of the iridium spark plugs and getting some NGK BRP6ES (or BPR7ES if you're running 18+ psi).