Ok so I am having a hard time figuring out what wrong with my car. I have searched the threads and thought i found some answers but still having issues. The car is a 94 and stock. here is what iis wrong with my car:

high idle (around 1500) - i have tried adjusting everything except the TPS. After my adjustments the idle will get to about 1000 and then over time end up at 1500 and hardly ever drops down.

low boost (3psi)- my boost guage reads 3psi and sometimes it wont even read any psi. it reads vacuum at 20. Today (after about 3 weeks of driving it) the guage went up to 8psi....but i didnt even feel the 2nd turbo kick in and i was almost at red line. I can feel the boost though and it feels like its pulling kinda strong, but i feel it should be stronger.

lag (weak acceleration) - i floor it but it takes FOREVER for it to respond (even without boost it feels weak. i can hear the turbos spooling too but it isnt going anywhere. sometimes it feels like maybe the clutch is slipping because after i shift it takes about 3-5 seconds before i can actually feel it grabbing and accelerating. (if that makes sense)

idle hunting - on stock ecu the car just recently started to idle hunt around 1300-2000. it was fine before hand and then one morning it just started doing that. i changed the ecu to a Mines ecu and it seems fine, except for the high idle. about a month ago i found a loose vacuum hose behind UIM and removed the UIM to find where it went. after i reinstalled everything it started idling high.

ive owned a FD in japan and it was almost stock as well.....just without all these problems he he. any info would help....PLEASE!! thanks

 

sounds like you have a vacuum leak somewhere? check all hoses and UIM gasket

 

Is your check engine light on?

 

i checked all the hoses and everything looks fine.

no check engine light.

 

bump

 

I have an idle hunting problem similar to your right now as well. I believe it to be a tuning problem or possibly my injectors are dirty/bad.

 

Where in CA are you? If you're in LA, OC or SD take it to either Tri-Point or Mazda Trix. Both excellent diag/repair shops.

 

thanks. im close to LA so ill see if i can swing by there. would anyone know what else could be the problem? (ive checked all the vacuum lines and they are good)

 

I had a similar problem so i upgraded all the hoses to silicone and found a few broken solenoids, i thought I fixed it after finding about 4 problems. It still had an issue with surging up and down very frustrating, I sprayed carb cleaner all over the upper and lower intake and then found my problem! The lower intake manifold gasket was made out of paper and was broken sticking out the sides. All the cars i worked on before that same gasket was made out of metal. Also a PINA to change on a stock sequential car.

 

thanks. well I called a guy who works on rotary engines and he helped me find a couple cracked lines......but still could not get it to idle comfortably around 700. It stays around 1000 at idle.

another issue i found is that after revving up or driving, it will take FOREVER for it to drop below 1500. whats weird is that i can turn on the headlights and then it will drop down to 1000....while the lights are on. then i turn off the lights and its all good.

we didnt mess with any electrical so i dont know why it would do that. any ideas?