Is there a way to test if the BOV is leaking? Will a regular boost leak test illustrate a problem in the BOV?

 

i changed my filter and it is not recirced back into the intake, i know, i know, i should not be running vta but i have been through many valves and other than stock my car has run best on the hks vta, including a jdm mr valve recirced, my car was vta long before i had problems too, and my bov is attached to the ic piping while the pressure is being run through the lines so i would have been able to tell if there was a leak

 

DO you have a vacuum gauge and is it steady (as can be expected with 272s) at idle?

And I wouldn't write off the dirty filter either. A semi restricted fuel filter can wreak havoc.

What plugs are you running?

 

what is your hunch as to his problem, provided his battery of tests? This is really puzzling

 

like i said i just changed the filter, i am running the ngk iridium bpr7iex or whatever is one step colder than stock, i just changed to them recently as well, and yes i have a boost/vaccum pressure gauge and it is pretty steady at idle with the 272's it bounces slightly with the sound of the cam but very slightly

 

haha, your telling me, this has been confusing me day after day i have no idea and will try anything at this point to fix it

 

I don't have a hunch yet.
The loss of power up top sounds like a lack of air since the car is running fatter then before.
Obviously the hot weather is a factor in this but it sounds like it is richening up more then it should under load. Which sounds like a lack of air or at least quality air (cooler, oxygen rich)
I am asking a lot of questions to try and narrow down what could be the cause. Generally a bad fuel filter will cause the car to lean out because the pressure is there but volume is lacking. But I have seen cars run with no light just a reduction of power with a filter you could barely blow through. I don't know what the life expectancy is on the stock filter since it's in tank.

 

Do you ever run race gas in the car?
Obvious reason I ask is if the O2 is contaminated the readings will be off but the computer won't know it.

Do you have injectors or an FPR on the car?

 

i have run race gas mutliple times, i am running stock injectors and do not have a fpr

 

know anyone with a spare O2 you can borrow?
They are freakin expensive at $250 on line but they do get killed by leaded race gas pretty easy. Most people who have replaced them have done so for the race gas reason.
Right now I would lean in that direction, of course the problem is the expense and difficulty of replacing it. Look around for O2 threads where people had to replace them for racegas reasons and see if they reported symptoms.

 

what o2 sensor are you talking about? i do have a few friends around with evos that i could borrow it from and then give back, also if it is my o2 and i replace it will it throw off my a/f?

 

also if it was my o2 wouldnt it throw a cel?

 

THe front O2 at the O2 housing off the turbo.
What happens with race gas is the sensor gets contaminated from the lead and it can not properly sense the oxygen in the exhaust gas anymore. Throwing of the A/F is exactly what it will do.

It is a real PITA to do it without an O2 socket because the heatshield has to be unbolted to get a wrench in there. The other problem is the potential for the threads to be frozen in the housing and it may not want to come out. If it doesn't turn easily once loose then it needs lots of PB blaster and a little luck and you can usually get it out. If oyu force it the threads on the sensor will be trashed.

 

so if i install a new sensor will it lean out my car? well if that is the problem, also would a bad o2 sensor make my car around 40-50hp less before i got my car retuned?

 

No because as far as the ECU is concerned it is working. It just is not providing the real feedback. All the Ecu cares is that it is connected and varies it's voltage. This is the same reason you can trick the rear o2 with a test pipe. The ecu can only detect so much.