so i have had a soarer when i was in japan no problems ever i bought this sc300 manual the other day knowing it had issues. its a manual as well so if im parked in neutral and rev it up it wont go past 5000ish if im driving in any gear wont go past 4000 or i dont try i can tell it doesnt like it and it feels slow and sometimes in some gears around 3000rpm it kinda jolts the whole car. any insight would be great my air filter is clean my guesses were fuel filter or injector or cats i have no idea though also i havent changed the oil yet but checked it and it looks to be a lil over filled dont know if that matters. thanx

 

Do you have a cel?

 

Yeah.. see if you have a CEL. Check sensors, vacuum lines. I think your MAF is faulty somehow..

 

no CEL weird i know im gonna swap fuel filter in the morning for kicks and maybe call a scrap yard and see how much a used maf is any pointers please post

 

changed the fuel filter black **** came out it was nasty but still same problem persists could it be that some nasty **** got past my filter and made its way down and is clogging another spot i.e. injector?

 

the rpms seem higher than the common 1jz problem, but I figured i'd ask just incase. Are you 1jz?

 

nope 2jzge one of my friends said maybe just maybe an injector is burnt out or severly clogged so 5 cylinders are hitting there redline but the 6th isnt so my engine is putting out its new 5 cylinder redline possible???

 

...they would all be rotating at the same speed. If it's severly clogged you could be getting knock maybe. Try one of those injector cleaners, they're cheap.
checking the plugs and coils is always the first thing I do when i have issues like this.

GL

 

Its probably a ignition issue causeing knock, which would account for decreased timing or the "sluggish" performance your feeling....

Start replacing cheap stuff like Spark Plugs, Rotor, Cap, and Wires....All of that can be had for less than $75.

Run some sort of fuel injector cleaner, and after about 100 miles let us know what happens.

If your still experiencing issues, It could be something like the maf sensor (doubtfully), oxygen sensors, etc.

 

pull the plugs you can get too easily 1,2,5 and 6. make sure they have proper gaps and the electrodes arent worn or cracked because it sounds like you are having a problem under heavy load.
also check your base timing (you have to jump some pins in the diganostic port to get the true timing).

you can also try the 12v fuel mod. maybe you arent getting enough fuel. the fuel pump ecu is known to go bad but usually shows up as a car not being able to start. doesnt cost anything to do and eliminates a few electrical grimlins.

 

WOW! I bought this car and the previous owner stated he didn't know anything about the acceleration problem. Looks like he couldn't figure it out and pawned it off on me. Either way I bought the car knowing it couldn't go past 4000rpm. Funny how I find a post on CL about the exact same car while I'm searching for an answer. I got the car to run a little smoother by just taking out plug 1 and 2 and reinstalling it. It now goes up to like 5000rpm but it still studders. It's too cold right now for me to take all the spark plugs out but I'll do it maybe over the weekend. I do have an extra MAF and ECU sitting around so I'm going to try to plug those up and see if it runs any different. Also the oil level light is on but the oil level is fine. Here's what I do know so far....plugs, wires, and dist. cap have been replaced and according to this thread the fuel filter also. Any help or suggestions would be appreciated. The fact that I came across this thread is out of this world. LOL!

 

Hmmm...so I switched MAF's and nothing changed so it can't be a MAF. Low RPM is fine but at high rpm it studders. I want to try the fuel ECU bypass and see if it's the fuel pump not pumping enough fuel at high rpms. Is their a way to diagnose this or any symptons to look for before I go and cut the wires? Also I read that the fuel pump doesn't shut off after you do this mod? That means it'll just constantly pump fuel? That doesn't sound safe at all. Can someone answer that for me?

 

Make sure the three hoses that lead into the throttle body, the holes are clear,not the hoses, disconnect the hoses and get some throttle body cleaner,use the extension that comes with the cleaner and spray into the 3 holes and clean. I hope this helps.

 

Well so far I redid the spark plugs and found out only 3 of them were changed and the other 3 were super old. Swapped MAF's and ECU's and the car still has no power after 4k rpm. My next step is the fuel pump ECU. Has anyone done the fuel pump bypass and are there any side effects?

 

Ok so I just did the 12v fuel pump ECU bypass and my car still bogs. So that eliminates plugs, wires, cap, ECU, fuel pump ECU, and MAF. I'm pretty stumped. I did notice some of the hoses were cracked under the hood but nothing major just small cracks at the ends. 1 is cracked from the valve cover to the intake arm and another one is cracked going to the throttle body. I'll have to pick up some replacement hoses tomorrow and see if that helps. It sucks to work outside in Minnesota winter. It's 10 degrees outside right now.