Overboost?
 

Car: 1992 JDM FD
Known aftermarket:

HKS Intake
Unknown Cat-Back Exhaust
HKS Intercooler piping

I am so confused right now about my car.

About a week ago my Cat. Converter was becoming clogged which led to me getting only .5 kg/cm^2 of boost (7PSI). My solution was simple, order a Apex'i PFC and a resonated mid-pipe to install next week. I know I am in a danger zone with amount of airflow I am getting and risk running lean on my motor.

Last night my battery decided to die on me and then within about 3 minutes revived itself without a boost.

Now, this is the weird part. After this odd battery death and resurrection I was able to go WOT again, which earlier I could not without exhaust back-pressure. So now my car is boosting 0.9 - 0.7 - 0.9 in 3rd gear ( 12.8 - 9.95 - 12.8PSI)

Any ideas as to how my cat. converter was able to unplug itself or even why I could be boosting at almost 13-10PSI?

Thanks for any help. Back to work for me... :icon_tdow

Did it feel a lot more powerful?

If you'r enot 100% certain it was, then I would check it with another boost gauge just to be sure.

Sometimes clogged cats are caused by the main element breaking free of the holders and being loose inside the canister. If it shifts around it will clog or unclog, so to speak.

Take it easy - 12.8psi is enough to do serious damage. I suggest you unplug your wastegate solenoid for now and that should keep your boost at 8psi.

Also, are you planning to port your wastegate when you install the midpipe? Even if your PFC is tuned to handle higher boost than 13psi, your stock fuel system won't do it. Until you upgrade your fuel system, you'll need to keep your boost down at 10psi, max is 12psi if your PFC is tuned for it.

Dave

Check your grounds and the connections to the PFC also. Batteries don't normally resurrect themselves. I had a bad ground once (cable termal was larger than battery terminal) and had intermitent boost issues until I figured it out.