ahad

heyy guys...ok this is gonna be a long one...I bought my fd 93 (N3A7) abt a yr ago...when i bought it it was running the FC single turbo with nothing at all. (crazy, yes i knw!) but yeah it was bone stock JUST a single turbo. So upon buying it i got rid of the single turbo and slapped on the 99 spec twins, avc-r, intake n downpiping. Now running stock boost, everytime the car hits 6-7k rpm the car hesitates as if it were a fuel cut or the fuel pump would give out or something its as if the car would get stick at 6-7k and then after abt 2 seconds being stuck there itd continue again normally. My first thought was am i running more boost than i should? Nope im not cuz ive got the boost controller on 10psi. I even tried less than 10psi but itd still give this prob. Next i thought the plugs so i got brand new plugs in. Didnt help. Then I figured maybe its a case of a weak fuel pump so i got a Supra TT fuel pump in. I put the fp in i start the car my first run the car became noticeably faster and almost a quarter of a second hesitation like i mentioned above n it was fine. So i figured ok it was the fp but after that one run the hesitations still there for 2-3 seconds everytime i hit 6-7k on the rpm. Now my mate has the exact same setup as mine, Intake, Downpiping, Supra TT fp and stock boost and he has no probs. Only diff is he has the 99 spec engine. Now after trying everything im wondering what else is there left to check cuz frankly im outta ideas. Questions like "was there something i was supposed to do while geting the 99 specs in that i didnt do?" but i dont know what it could be im absolutely stumped. I met a guy n hes like oh yeah i had the exact same prob! i said howd u fix it he said "i got a 1jz"...
Cheers

ahad

need of some serious help here guys...

adam c

iTrader: (2)

I had a similar problem. Turned out to be the ECU going a little too rich at high rpm. The problem seemed to go away when my engine temps got up to around 200 degrees. I think the ecu was reading engine temps lower than they were, and richening the mixture too much. Have you tested for the hesitation under higher engine temps?

I now have a pfc, and the hesitation is gone.

bewtew

iTrader: (7)

check all the vacuum hoses under the uim. sounds like a loose hose somewhere.

ahad

Wouldnt resetting my ecu rid that issue if it were? But yeah ive reset my ecu quite a few times cuz but no use. Yes i have tested it udner high engine temps its the same everytime.

will do but what makes u suggest its a loose hose cuz the hesitation comes at almost the exact same rpm every time

bewtew

iTrader: (7)

i had the same problem when i would run the car WOT. i thought it was the plugs so i changed the plugs,wires,fuel filter and i still had the same problem so i took at look at hoses under the uim and one of them was loose.. i plug it back in and made sure all the vacuum hoses were nice and tight and vualaa! problem solved. i hope you fix the problem but im 90 % sure it has to do with the vacuum hoses.

bewtew

iTrader: (7)

http://www.autosportracetech.com/RX-...leshooting.htm



http://www.autosportracetech.com/RX-7/vacuum.jpg



Good luck!

adam c

iTrader: (2)

Resetting the ecu will not change its programing. Perhaps you have a different problem than I was having.

Dudemaaanownsanrx7

iTrader: (23)

have you checked the coils, and changed the wires? check all your grounds/ clean them. It could be ignition or fuel related they both feel similar. Is your FPR vacuum hose hooked up? have you changed the fuel filter? 6000-7000 is where most rotaries make peak torque and the car requires the most fuel. if you could put a wideband on there you could see if its going lean. Or if you had a fuel pressure gauge you could see if you're losing fuel pressure.

DevilInASevin

had a similar problem---coils/ignition was going bad. replaced all my vacuum hoses too. that solved the problem.

Sideo

it seems like we have already ruled this out, but when i installed my 850's it would feel like it was hitting a rev limiter around 5k until i leaned it out more then it would rev just fine.

ahad

hmmm yeah it could be the ignition/coils havent changed those. I had the fuel filter cleaned as an attempt to fix the hesitation issue but that didnt do the trick either. So from what i can gather its either the ignition or the vacuum hoses. Im gonna need to take time out to check all the hoses sigh...ignition ill have a look at soon. I got the FP changed so that wasnt the issue although for the first run as i mentioned it almost didnt hesitate.