this is a tricky search guys, help me out... seems like there are so many random sputtering issues that are slightly different than mine out there... so my Issue is the car chokes and sputters unless i have that perfect light throttle sweet spot on the gas peddle.. it boosts fine and the sputter does not seem to be boost related.. light throttle, heavy throttle doesnt matter.. the throttle has a little Delay as well when i push it down and it even sputters when the car is NOT under load.. as in if i rev it up in neutral in the driveway there is a slight delay/stutter and when the car is under load its really continuous sputter to the point the car jerks all over the place and i can barely drive it... with the perfect amount of throttle it will stop sputtering and take off like a bat out of hell...
the car is a broken in rebuild, with an rtek 1.8, 720 primaries and 1000 secondaries, whalbro pump, t4 turbo, fmic etc...

the problem slowly progressed to worse and worse sputtering over time, it started doing it randomly, now it is barely driveable... since the sputtering began, ALL emmisions have been removed, UIM has been removed and re installed, ALL Vaccum have been redone twice.. Fresh TPS sensor installed... HELP ME PLEASE!!! i have a Time attatck session in 3 weeks and have a bunch of competitors im sure to blow away assuming my **** is all working!!!
i have a different AFM and atmospheric pressure sensor to try maybe?? possible my O2 sensor is toast maybe?? i dont have a fuel pressure regulator yet, possibly to much or not enough fuel pressure??? the GAS MILEAGE was Horrendous driving to my friends shop yesterday..

 

Can you do any data logging? Also did you calibrate your new TPS with the rtek?

 

+1 on checking your TPS.

 

See if this is similar to your problem.

https://www.rx7club.com/2nd-generati...umble-1064261/

 

Everyone's issues may be slightly different, but usually the fix is the same.

 

My issue sound just like his.... I didn't do the soldering on my Rtek however... I sent it to them to have it done... Is it possible I did something to f##K up my ecu??

 

I have an extra n332.. Maybe I try installing it and taking it for a spin?? Probably gonna run like.**** with all the fuel I'll be dumping in it on the stock ecu...?

 

So after figiting with a few things, 1 new plugs changed things significantly :-o... Duuuh :$
Now the only issues I'm having are a hesitation when the secondaries come on, and the throttle still has a a wierd little delay when I engage the pedal... After unplugging and replugging in the boost/pressure sensor my factory boost gauge works again!! It's never worked!! I'm gonna assume it needs to be re ground which often cures the famous secondary injector hesitation... And maybe the sensor itself is faulty or has dirty connections??? could this sensor not functioning correctly cause the throttle delays ya think??

 

Definitely address the grounds. Also, set the TPS to make sure it's not the cause of the lag.

 

do you have a modded throttle body?

 

Yes sir I do! This could cause the pedal goofiness?

 

The downside is engine speeds under 3,000RPM will cause hesitations if aburpt throttle inputs are made; you cannot romp the throttle if the engine is revving under 3,000RPM. If you do, you will be rewarded with a slight bog, as the intake velocity is not fast enough to handle such a large transition in the throttle body due to the removal of the extra set of throttle plates. One of the purposes of the extra throttle plates was to provide progressive transition of intake velocities when romping on the throttle at such low engine RPM speeds. On a good note, if you avoid this problem by driving smoother with the throttle input, you are learning to be a better driver!

taken right from FC3S Pro's write up on the mod

 

but you also still need to test the TPS and grounds