shlounek

iTrader: (1)

OK,

I am not sure if i submitted this thread in the right forumn but here goes. I have a 92 SC300 5 speed, I recently changed the clutch. And the car feels slower :'(.

I took it to several mechanics to get a second opinion on wether the cluth install was bad and thats maybee why the car feels slower. But it turns out that the clutch has no issues. But two or three mechanics suggested not enough fuel is comming in and therefore the timing on teh car changes cuz there is alot of knock in the engine so teh computer electronically changes timing to avoid knock.

I took it to Lexus, but unfortunetely it seems like I am the few people who own SC300 5 speed in Canada. So the Lex tech had fun with teh car whne he took it for a test drive but quite honestly he has never driven an SC300, and a stik one to add to that matter, and said he sees nothing wrong with the car. But thats not enough for me, I have a 5th sense when it comes to Lexus underperforming.

Here are the issues:
1. Problems starting the car on hot days
2. Lag on power on rpm lower than 4000 RPM.
3. when filled with 93 octane instead of 91 considerable power is felt but not liek how it was.
4. Oh yeah the car was parked in my garage all winter I brought it out a month ago from hibernation.

I was told that maybee the fuel filter needs changing, or the fuel system cleaned but i am in confusion.
Please help anyone, BTW i will get it Dyno'd tomm to see the fuel/air ratio and HP output.

Thank you.
Ali

gadgetSC

Might I suggest you try taking a look at the spark plugs, wires and air filter. Any one of these could hurt your performance. When was your last tune-up?




gadgetSC-t

mrshabo

i have the same problem as you but i have a dying clutch. when i pound on my car on 4th gear you see the rpm needle raising then it stays at the same and then drops a bit and then go back up... weird huh? i had this problem in my maxima too. i changed the sparks and the problem went away. i'm gonna change my sparks and wires on sat. i would tell you if it fixed the problem but i'm installing my clutch too so i gotta break it in... tell me how everything turns out

legendary

how many miles are on the car?

I would also suggest in addition to changing the fuel filter, a full induction service. These cars also run very good on 93 octane, so you might want to stick with that as well.

93 LS4

What kind of clutch did you install? Hopefully not a rebuilt kit, those pressure plates are usually weaker then factory spec and will cause your disk to slip.



HP
SC300 5speed

shlounek

iTrader: (1)

Thanks for the help guys,

sorry for the late replies, it has gotten WORSE now, i hear a hissing sound from the near teh gas tank, maybee its teh pump.

The mileage on the car is 104,000 miles but i doubt any tune up was performed on the car when i purchased it. as for the clutch i am not sure of its rebuilt but i must ask. Purchasing a clutch from ebay maybee was the PROBLEM :'(

Yo spruce what type of clutch did you install, and was there any throw out bearing noise when you first installed the clutch when shifting from 1st to second 2nd at slow speeds. (slow meaning 25 miles and hour)

I might do the spark plugs and wires (Bosh +4 platinum plugs) but i do not know if different kind of wires actually matter. If anyone also have suggestions in what works best in the car please advise.

LEGENDARY: is a full induction service were they somewhat clean the gas lines and fuel injecters, and how much does that usually cost at lexus.

ALSO if anyone knows a good mechanic within the detroit MI area, please give me there numbers, i almost strangled my mechanic teh other day for teh clutch job, cuz i have feeling he didnt grease the throwout bearing also.

Sorry for the tons of questions.
Ali

mrshabo

throw in some fuel injector cleaner. and clean out your throttle body. I didn't think that the fuel injector cleaner would do anything but i noticed a little difference. Also clean out your throttle body the real way.. not with those cans. You might as well do that while your changing the sparks and wires. try doing 2 treatments of the fuel injector cleaner see if that helps.

O. L. T.

iTrader: (17)

Sounds like when the tranny was dropped, something didn't get hooked back up.

Edit: or was twisted or pinched.

legendary

Induction service that I am referring to is something like what you said. It impacts the injectors, throttle body, fuel lines etc. I think it will ocst in the neighborhood of 69 - 89 dollars. If it has gotten worse, you should have them reinspect their work. I am sure you got at LEAST a 3 month/3,000 mile warranty minimum. MAKE them fix it.......ouch....wait, if you got hte clutch from ebay, did you inspect it? Was it generic? I just realized something...if you brought the parts for them to put on, there is probably no warranty. Let us know man. You may still have a point in reagrds to the TO bearing

shlounek

iTrader: (1)

wuzz up,

For sure i know its a fuel problem, I tried that fuel injector cleaneer crap but it was worthless, So i really dont want to bother with that crap. Does anyone know what that hissing sound means comming fom the back, it sounds like a motor or something, that is why i thought it was teh fuel pump, or maybee something is blocking the fuel flow creating that sound. Cuz if it was teh fuel pump then quite honestly the car would not work since the pump would not work.

Is the fuel filter, and cleaning the throttle body hard to do, i have a lil mechanical know how, cuz i wanna do one thing at a time since i really want to pin point exactly what was wrong with the car.

I inspected teh clutch it seemed fine, it was a SECO clutch and an NSK throw out bearing that i bought from AIMCO on ebay, the guy had pos feedback from ppl who had supras who installed his clutch. Yeah you guys are right its like he didnt install teh gear right or something. >>>> When i want to move teh car from a dead stop, to get teh gear into 1st, i have to shift to 2nd first and tehn to 1st, it never used to be like that. Quite honestly even my clutch was bad for any reason it wouldn't create problems like that.

BTW, yesterday night my friend with a 97 BMW 528i auto was dying for a race, and i didnt want to, cuz my car is still not up to its performance, so we raced, and raced and raced, 12 times to be exact beat him all the times, one time i gave him a headstart cuz i did a bad start, onnce i misshifted, and one time my gear just didnt want to go into 3rd, but the road ended hehe. I was pissed at teh end of teh night cuz i should have beat him with car lengths but my car is very ill and many races were close, but the SC300 pulls hard. The 5 speed on these cars make them crazy.

Ali

mrshabo

hrm... so let me see. you bought new clutch installed it and car has problems. then you raced with a new clutch that isn't broken in yet? hope you didn't launch it too hard..

shlounek

iTrader: (1)

thats wierd,

quite honestly this is the first time i heard u have to break in a clutch, maybee my mechanic is just dumb, he told me no need for break in. And also many of my friends think the same that there is no break in period. Dont worry my car isnt giving good power so i doubt that the clutch is working its *** off.

BTW tomm i will order fuel filter, and my fuel pump looks like its reaching its life. So i might need a new pump. I will do everything step by step to see any performance increase. Is the fuel filter difficult to change, i know its under the car somewhere.

ali

mrshabo

i dunno man. all my friends had to break in their clutches. even in the box there is a paper that says that there is a break in period..

93 LS4

I just installed a new Toyota factory clutch and all my problems are gone. No more bouncy launches, no more pilot bearing noises. The owner before me installed an E-bay $99.00 kit special. It was a (DK) Dainking, which are usually ok, but the pressure plate was soft. I think it may have been a rebuilt kit. Anyhow the car feels much better now, smooth shift without the Notchy shifting I had with the $99.00 clutch.


Change your fuel filter! I had power loss too, and when I removed my old fuel filter all I got was dirt. It’s located on the drivers side rear near the rear wheel, and easy to replace! It made a noticeable difference for me when I replaced it.


Good luck,

HP