dizzyroc

just throwing this out there cuz the question has not been asked .... has the car sat for an extended period of time? or did this just happen one day to the next?

Roel2377

Nope its my daily driver one day it was good and he nxt day bamm it will turn but won't crank

SCereal

iTrader: (4)

That is frustrating. Still not firing those 4 cylinders with the new ECU? Does it pop or sputter at all or just crank and crank?

Roel2377

Yeah it just turns and turns and it's dumping alot of fuel to the four that are working... Spark plugs come out wet

Roel2377

I finally had to take my car to the shop well after a day or so they called and said it was my ecu and it's fried but it's crazy I just got it rebuilt and it's fried up again fml... Does anyone have a 98 sc 400 ECU and it needs to have the key that goes with it I heard or it won't work

fourstars

there is NO system to test a ECU unless you installed it on another working running 98 sc400. and rebuilding an ECU is not worth it these days. just buy a new one on ebay for $100 or so. if you borrow one and that still does not solve your issue, then you never had an ecu problem. if 1 side of the head is shooting sparks and other is not, then you got your self a wiring issue buddy.

put your igntion on and test the power coming out from your igniters. there should be power on IGF 5v i think and when you crank theres should be about 1 - 1.5v on IGT. if there is voltages then you need to get a test light and connect it to + terminal of your battery and backprobe that IGT wire on both igniter, you may have to use a pin or splice a wire. once you do that you should hear sparks from the coils. if you DO hear sparks on both sides then there is no mechanical issues with, coils, igniters, leads, distributer, etc.. your issue is with cam and crank sensor or wiring. if you DONT then there is something wrong with igniter, coils, leads, rotors, etc...

Roel2377

You see I can't just use another ecu 98 lexus and up Ifguess I use another ecu I have to take it to lexus and reflash it to work with mine which also cost and my ecu is expensive I saw one only on eBay for almost $300 I'm not sure if your read all the post but I check all the coils and there good and I can't even use a code reader it wwon't connect which leads me it's a ECU problem