when i boost sometimes my car does not pull like normal. Its like the boost gauge says 7psi but my car does not go! Normally it will go to 7psi and my head gets ripped off!

What is my problem and What causes it? thanks

 

Are you intercooled? Explain "car will not go" does it just sit there or does it pull significantly less then usual or just a little bit less? My first guess based on the lack of information is that your intake air temp gets warm enough to where your experiencing power fade, Does this problem come and go in one trip or does it come and go anytime even at night when its cool out?

 

My car will not go: it pulls significantly less. yes i am intercooled and it does not matter if it is day or night, it does it like every fifth time i give it boost when cruising(barely,half,& full throttle)

hope this helps

 

I would first check the intercooler piping couplings and the plugs.

 

ok well I have the same problem as you sometimes but its not as bad as yours and up until now i passed it off as normal, judging from my experience with my car I think whats happening is when you punch it after cruising (at more than 0" hg, no boost) your fmu (judging your using one) is relaxed at base pressure and when you punch it and it senses the raise in pressure it takes a little while to kick the pressure up to whatever it should be and whats happening is, until the fuel pressure gets to the tip of the injector your kinda starving for fuel for the 3/4 of a second it takes to force the extra fuel through the injector via significant increase in pressure. In other words the boost gets to cylinder a little bit before the extra fuel gets there, your experiencing something similar but worse So I'm going to suggest doing a fuel pressure test under boost when the car is fine and doing it again when it acts up and compare results if there is a difference greater than about 10psi (of fuel) before and after then it could be a weak pump or a defective FMU (leaking diaphragm possibly). This is all theoretical, correct me anybody.

If your system doesn't use an FMU setup then you can throw the above theory in the trash but thats all I can think of (at least now I know why mine does that). Peace

 

Im going to guess its a fuel issue. Your running super rich or maybe lean (bad). When i was running way to rich i would go into boost and it just wouldnt feel like i was going anyways. I fixed the over rich problems and wow what a difference. 5psi feels like 7 or 8psi before.

liam