Hesitation and bucking at 3.5k to 4k
 

Help,

My 93 rx won't accelerate over 3.5k to 4k in any gear because as soon as it hits it bucks. Also to really doesn't want to let go at low rpms. It is definitely hesitating since it won't allow me to use full throttle.
It is also eating gas like you would not believe. I know it is running really rich. Just replaced the plugs and drove it but plugs are full of dry soot.

Single turbo
FC
hks twin power
Two additional fuel injectors in the intake elbow

Bought car modified and has run great until i ran it out of gas the other day. Replaced plugs, wires, and fuel filter.

Thanks,
C-low

have you tried disconnting the battery negative for a while? almost sounds like its stuck in limp mode. not sure if your ecu has this or not. possibly something else with the ecu also.

What ECU does this car have? Cant have the stock one with additional injectors. I suspect the additional injectors are not working right or setup correctly.

I have disconnected the battery a lot. I have an fc commander. It idles a little ruff. It will revive up but not as easy as normal. It also seems like there is no turbo lag. I have replaced all of the vacuum lines in the rats nest awhile ago which helped with other issues. It is a beast and is very fast on the autobah. I have had up to 170mph and it will go faster so I need it fixed so I can run do German cars.

It could be a bunch of stuff. I had same issue, but mine would back fire at wot and not build boost.
Does yours builds boost til 4k rpm? Back fires? The more detail you provide , the more help you will get.

Sounds like it is misfiring while idling. It does not want to die though it still idles strong. While driving there is only a sweet spot on the pedal that will allow me to accelerate. If I push to much or not enough it will start to hesitate. Not saying that the sweet spot accelerates normal either but it is the best spot to accelerate. It does boost until about 4k and then bucks and after that I always let off because it is very violent. I have gone through a half a tank in about 70 kilometers. Brand new plugs were full of soot in that just that 70 kilometers. Doesn't blow a lot of smoke but when it does it is either black which is fuel or everyonce in a while blue smoke. I did a compression test so I know that the seals are good.

Sound like secondary injectors or ignition issue. Did you check your coils? Grounds? Clean the secondary injectors. What is the fuel presure?

By two additional injectors in the elbow, does that mean you have a total of 6? If so, maybe start by removing the additional fuel from the equation given that its puking smoke and near fouling plugs in just a few miles. I totally agree with inspecting the ignition and cycling the computer. But maybe a quick test with the injectors unplugged will help you narrow down if its a fuel/computer issue or something else. Back in the day, Chrysler had a delicious problem with coolant temp sensors...when (not if) they failed they would tell the computer the engine was at -100F or something ridiculous like that. Injectors would dump in so much fuel the engine would all but stall violently after a minute or so of chugging a smokescreen across the yard. Anyone aware of problems along this particular line?