redforeva

iTrader: (2)

got a question for you guys

my car just stalled out a few days ago for no reason, power steering turned off and car just came to a stop

went to the shop, cleaned out the iacv and replaced sparks and wires (spark #3 was cracked, wires were 20 years old), worked again

recently my sc300 has been idling very roughly (2,000 at park...) and dips into the low rpm's while driving and then slingshots back up (kinda like stuttering), very rough idle sometimes when i come to a complete stop almost to the point of shaking

anyone ever have this kinda situation? i'm not so sure on what to do

i was thinking it might be my MAF or throttle body..but...i'm really not too sure

LEXZ400

use Bosch fusion plugs ( un-gapped )
replaces fuel filter
bypass fuel ECU or buy a new one

ihiryu

iTrader: (7)

Sounds like you're on the right track. I think you have a vacuum leak considering you have a 2000 RPM idle in park.

You also might wanna check the TPS

Arkansas

been having the same kind of problem with my 92 SC400. mine will idle at 1500 rpm then almost stall out with i press on the gas. a friend of mine said something about the fuel pump fixing to go out. it took forever to crank over last time i started it, and when i did have it in drive, i couldnt get it to move my pressing on the gas. all it would do was creep along just from the rpms at idle. i cant figure it out

LEXZ400

it could be IACV bearing is the problem or fuel ECU
http://planetsoarer.com/IAC/iac.htm

SCFlex

Thanks guys this info. is great. I haven't checked or noticed the rpm's but I do periodically get the chocking and turning off. Then some days (for days) it's runs perfectly. It has not passed smog due to the timing. Smog guy said it would pass if I could just get adjust timing. Was just told to have timing adjusted to 10 degrees, but best guy could get it was 13 w/out taking more time and getting in there to completely turn it. He also said if he got it to 10, I would lose power and that I do need to have the TPS checked. Don't quite understand, but was also told that maybe Toyota/Lexus may fix/replace TPS for free as this is a recurring problem w/this car. 93 sc300. Think I can find a TPS used, jk yard maybe? With these issues, wondering if car is on last leg..256000miles, not sure how much $ needs to be spent to get it healthy and passing smog. Any thoughts, on cost..will check out/replace sparks today.

Arkansas

How much do those cost to replace? And ur also the first person thats given much advice over fuel pump/filter or cats clogging up. Thinkin of replacin the filter and swapping to a walbro 255 with my stock motor.

LEXZ400

It's a expensive parts plus labour 80 bucks.

[http://www.theautopartsshop.com/auto...alve+1993.html

LEXZ400

http://www.drivewire.com/vehicle/199...control-valve/

Arkansas

that thing almost cost as much as i paid for my car!!

LEXZ400

Owning SC is freaking serious, it drain your wallet for parts.haha

Arkansas

Will an IACV from an ls400 work since its the same motor?

redforeva

iTrader: (2)

yeah, the IACV should be fine for your car

anyways guys, thanks for the input

i brought it back to the mechanic, they said it was the fuel injectors stuck open, they replaced 2 of them, and now my car is a goner blowing white smoke throughout the neighborhood feeling like a lawnmower

im gonna guess that the old fuel injectors were crap and were clogged so that not much fuel was being pulsated even if they were wide open the whole time but now with new ones, it's a nightmare

so, i'm gonna replace the ecu and tell you guys what happens

Arkansas

do believe this man might be right on the vacuum leak. been reading stuff on the net and thats what sounds like is happening to our rides. the fun part will be tracking down where exactly the leak is. gonna have to get me some carb cleaner and spray along the intake manifold and a few other spots to find where its coming from. the net also said it could be a bad EGR (or ERG...can remember the correct way it is....been working for about 16 hours today.)

ihiryu

iTrader: (7)

EGR.

Soapy water works too, but I do recommend carb cleaner, just make sure you get more than one can lol.