BoostFrenzy

I've searched yadda yadda and I don't even know if I can intelligently describe my situation on a computer, but here goes...

First of all, vacuum is in the ~14 inches range, car runs/drives beautifully with a good boost pattern, starts with no smoke easily warm or cold, shows NO signs of engine failure, gets great mileage on the highway, doesn't stutter or otherwise do anything that would make me think the engine has issues.

No check engine light or stored codes (light turns off when TEN/GND are connected), engine runs good at whatever idle rpm and airpump is functioning, i do notice at cold start if not started in gear and AWS activates it doesn't shoot instantly to 3000, it kinda works it's way over to 2500-2800ish over a few seconds like it's laggy

Problem is firstly, the vacuum, seems to be indicative of a leak somewhere, also when the engine is running there's is a tick that increases if you rev the engine (the pitch doesn't change but the tick speeds up as you rev up) coming from the center/rear of the UIM underneath it sounds like, could be a vacuum leak, could be a solenoid, could be just the injectors, but i don't think it's supposed to be there

Also, the idle also suggests a vacuum leak, when it's warmed up with the lights/accessories off, it'll idle normal around 750ish, but as you drive around some more and come to a light again, it'll start sticking @ 1100ish instead, this can be solved by turning on the parking lights which drops it to 900, then again turning off the parking lights at this point brings it back to the normal 750 for awhile

Car seems to run excessively rich under boost, again suggesting a vacuum leak, while hearing no "leaks" under boost and having a good boost pattern, this leads me to believe no boost leaks are present, once again seeming like a vac leak

I've had things somewhat apart fixing other issues, replaced some check valves etc, checked to make sure nothing is leaking up front on the UIM, however I have not removed the UIM (kinda scared to), but since everything else is working normally and the turbos are working properly that leads me to believe the rats nest is ok

The car has 63k on it and only mods are chopped airbox w/ K&N dropin and a downpipe

I guess i'm looking for someone who's seen the above or has had a small vacuum leak with a low vacuum reading and what their solution was

thanks guys, i'm getting VERY close to having a perfect fd!

RX7Wishing

First thing to do is the obvious. Check under the pressure chamber for vaccum lines that may be cracked or popped off. Second i would reccomend pulling off the UIM (ALOT easier then it sounds) and inspecting the rats nets. Have you done the vaccum hose replacement mod yet? If not, now is the perfect time to do it.even at 60K on the clock the car is still 11/12 years old and **** gets brittle. Vaccum leaks can be anywhere. IF it is an obvious leak then spray a little bit of starter fluid around the edges of your UIM and if you can your LIM. see if your idle changes at all.. if it does, then you found the leak. Tracking down vaccum leaks on the FD is no fun job. As you can already tell

1QWIK7

iTrader: (33)

i noticed i had a leak when i would only boost 4psi and found out that one of my IC couplings was coming off the pipe, like there was an 1/8 of an inch of opening between the coupling and the pipe..so i put the coupling back on securely and tightened it and i got my 8 back (yes its only on 8 for now)

now im having the same problem..i am only getting 4-5psi and even when im not boosting, when the car is fully warmed up, i could be revving in any gear, 2nd or 3rd and when i let off, the vaccum would go to 21-23..but then when i put it to neutral, it would go back to normal which is 18..i start to drive, be in gear, let off in gear and it will go back to 21-23 until i go back to neutral or back on the throttle..

i have yet discovered whats wrong..ill look more into that..