im also going to check my fpr thats the only part of the fuel system i havent replaced

 

Yeah, I read once that our cars run rich from the factory so you shouldn't need a tune when installing long tubes, I didn't. Strange Problem!!

 

easiest way to check the fpr is to remove the vacuum line and smell for a gas scent. this will indicate the fpr diaphragm is leaking, another more accurate test is to attach a fuel pressure gauge to the schrader valve on the fuel rail. look for 40~ psi with the vacuum line on and 43~psi (simulates WOT) with the vacuum line off.

 

thanks everyone for there input, it is a very strange problem.

 

LT's can be installed without tune, If I am not mistaken, the hypertech makes the timing curve fixed, and only uses the input of the knock sensor (instead of constantly changing like the knock module is supposed to do), it's possible you have a bad knock module, or the wrong one, and the hypertech is just masking that. just a thought off of the top of my head.

 

last night i took out the LT4 knock mod i put in last weekend and it made no difference so i put the LT4 back in again

 

my Jet Hots have a leak also. from the driver side, where is your leak coming from?

 

passenger side, thought it was the EGR but redone the block off plate and its still leaking so i going to replace the gasket

 

probably, the header bolts will back out after a few heat cycles so within the first few weeks or so you have to keep checking them

 

i have the stage 8's so they cant back out, two of the ports were leaking

 

my car ran GREAT without a tune with LT's.. Went .3-.4 faster..