so my sc300 1997 has been acting up, when i’m driving, it won’t go past 4-4.5 rpm and if i keep going, it’s sputtering, can’t floor it or anything. i’ve changed fuel, air, sensors, ecu, & even the transmission. no one @ the job knows why it’s doing it, but maybe there’s someone on here that might. please let me know

Throwing parts at it, is just gonna make it more expensive and ruin your owning experience. It appears you may be experiencing fuel cut off at high RPM. I would start by testing the fuel pump and the fuel resistor/fuel ECU. Even check relay and fuse to ensure those are good to go. I don't think these 2jz have ignitors, otherwise I would say check the ignitor to ensure that's also good to go. I'm more familiar with the 1uz vs 2j. Someone with more knowledge and experience will chime in.

1992-1997 2JZ-GE engines DO have igniters. They just aren't the same as a 1JZ/2JZ-GTE igniter unit. They use a single ignition coil that feeds a traditional distributor (which has a cam position sensor built in) to provide spark to all six spark plugs.

OP, also check into whether or not your factory Fuel ECU is operating correctly. You can bypass it into "Test Mode" at a full 12V to see that the "high load" operation mode is working correctly. These Fuel ECUs are set up to run the factory fuel pumps at 9V at post-cold-startup idle (when the engine is warm enough) and at low engine speeds and/or low load conditions. However that ECU kicks into throwing 12V at the fuel pump for any high load situation.

I'm not sure that your issue is a Fuel ECU malfunction but just through I'd mention it.

You might also try swapping to another known good 92-97 SC Karman Vortex MAF unit. Just the sensor. There is no need to replace the metal housing that it bolts into.

i will get back to you guys on that thank you

Is your 4.5k limit when it's under load, or also in neutral?

both, under load and neutral

the very last thing i have not checked is the igniter, i just ordered it & i’ll replace it tomorrow. if it’s not the igniter than it has to be my ecu, we have diagnosed & replaced everything that could possibly cause that issue, even through there’s no blown capacitors in it, there’s always the chance i got a bad one. i will update you

i have changed the ingiter, the maf, the injectors, the fuel filter, ecu + reprogrammed, the fuel pump & did a fuel ecu bypass & it has not affected the rpm’s. does anyone else know what could possibly be the issue, cel finally came up & it’s temp sensor code, too rich, & egr. if im not mistaken the temp sensor code also comes with too rich or too lean, & my egr code is from the egr delete that i did. please help haha, it’s a 1997 SC300 A/T non vvti