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Old 04-30-14, 12:27 AM   #91
BobSmith00
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It's more or less then solved possibly.
Lexus dealership figured it out after "3 hours" of inspection.

Will report back if it was the fix that we needed.
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Old 05-25-14, 03:32 PM   #92
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Originally Posted by BobSmith00 View Post
Further info.
I do not believe the "new" ecu is why the car ran today for 40ish seconds.
I think that was a product of the car sitting for 3 months without anyone messing with it.

The "new" ecu in the car, the car now does as it did.
It throws no codes, but it only runs for a moment. Just as it did in the old youtube video I have.
1996 Lexus LS400 Issue - YouTube

I am somewhat at a loss, its dark out now, so I likely won't be messing with it anymore tonight, and maybe none morrow.

Any thoughts?
holy crap thats what ours is doing plz update.. whats the solution.

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It ran for about 40 seconds.
It sounded like it should.
All the instrument panel lights were bright.
And then It died.
The Check light was blinking.
So I found my odbII reader.
Gave me 4 codes.
p300, p303, p304, p308

That seems to be some cylinders misfiring?

Some further googling suggests the firing order is 1-8-4-3-6-5-7-2.

The fact that I had a "random misfire' on 8,4,3. Makes me wonder if that is some sort of hint to what happened? Since those correspond to the firing order?
ours has no code but its doing what yours is doing.. haqve you found out anything? should i get another ecu? the one thats in the car is the newer 89661-50304 and it looks flawless inside.

what ours is doing is identical to yours. and i have replaced fuel pump new alternator there is pressure at the rail, there is spark, the ignitor and coils are all good, the compression is good all the plugs are good too. this sucks man! :/

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It's more or less then solved possibly.
Lexus dealership figured it out after "3 hours" of inspection.

Will report back if it was the fix that we needed.
any word on what it was?
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Old 05-29-14, 05:40 PM   #93
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guys please what was the solution or help me out so i can test more stuff. i just tried a good ecu and no change same thing. vroom. then turns off just like the video he posted.. BobSmith00 please tell me/us what the problem was so i can fix our ls400 its been down for 8 weeks man.
LScowboyLS, Yamae guys please PLEASE
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Old 05-29-14, 06:08 PM   #94
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hardly anyone reports back..which in turn wastes everyones time. so..everyone replaces or fixes their ecm's because every single thread is littered with a link to the ecm fix...tried to quell that long ago and now people are finding out first hand that its not a fix all...u don't start fixing ur car from the ecm back. I realize capacitors have a limited life..they all do including the ones in ur video card or motherboard..but unless a ripple test is done proving its bad..then ur rollin the dice.
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Old 05-29-14, 06:21 PM   #95
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There are many items that the ECU disables the fuel pump to work aiming not to damage the engine or to prevent the air pollution. The link below is one of the examples. This one was caused by the disconnected MAF sensor.
http://www.clublexus.com/forums/ls40...x-problem.html
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Old 05-29-14, 06:59 PM   #96
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thanks for responding guys!

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hardly anyone reports back..which in turn wastes everyones time. so..everyone replaces or fixes their ecm's because every single thread is littered with a link to the ecm fix...tried to quell that long ago and now people are finding out first hand that its not a fix all...u don't start fixing ur car from the ecm back. I realize capacitors have a limited life..they all do including the ones in ur video card or motherboard..but unless a ripple test is done proving its bad..then ur rollin the dice.
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There are many items that the ECU disables the fuel pump to work aiming not to damage the engine or to prevent the air pollution. The link below is one of the examples. This one was caused by the disconnected MAF sensor.
http://www.clublexus.com/forums/ls40...x-problem.html
ok so things i have done..
test fuel pump,
run 12v straight to pump
replace pump
replace alternator
tried different maf
iacv is clean
ecu is the good one 50303 also tried another 50303 same thing
there is fuel to the rail, no injector pulse
ignitors fire the coils with the bypass test

there is one thing though.. there is a 4 wire plug next to the ecu with a brown wire a yellow and green and another color wire all just connect together in that little plug. they go ino the sheilded wires going into the ecu.. those 4 wires the insulation is like bubbled so to speak.. so the wire inside is just floating in a baloon of wire insulation..

Click the image to open in full size.

im gonna test the cam sensors.. but there is NO CODES though. nothing. i tried a cheap scanner and a expensive snap-on one..
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Old 05-29-14, 08:24 PM   #97
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Similar symptoms in this video. An air leak threw off the mixture leading to immediate stall.

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Old 05-29-14, 09:36 PM   #98
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Similar symptoms in this video. An air leak threw off the mixture leading to immediate stall.

http://www.youtube.com/watch?v=w2tLU...share&index=32
its not an air leak i check that already.. this is frekkin crazzy man. only thing is the injector wiring left pretty much..

cam and crank sensors are good..
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Old 05-29-14, 09:55 PM   #99
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Quote:
Originally Posted by Cleanshots View Post
there is fuel to the rail, no injector pulse
ignitors fire the coils with the bypass test

there is one thing though.. there is a 4 wire plug next to the ecu with a brown wire a yellow and green and another color wire all just connect together in that little plug. they go ino the sheilded wires going into the ecu.. those 4 wires the insulation is like bubbled so to speak.. so the wire inside is just floating in a baloon of wire insulation..
So you found the "no injector pulse". That's a big problem. Then your next step is to find out why so.
How did you check injector pulses?
Did you observe the actual waveform?

Regarding the shield wires, they just surround the center wires to avoid the electromagnetic interferences. As long as all 4 are connected to the ground line of the ECU with a low resistance, you don't need to worry about.
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Old 06-01-14, 09:19 AM   #100
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just pulse i checked for the injectors.
its not the cam sensors or the crank sensor. there are no codes in the ecu and wont throw one either but any time i unplug something it throws a code so its working properly.. it has to be something simple and stupid that's causing the problem i just don't know what it is..
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Old 06-01-14, 08:54 PM   #101
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just pulse i checked for the injectors.
Let me confirm. Do you mean that you felt the pulse by your ears as sounds or some mechanical vibrations by your hand touching it?

The ECU is checking the continuity of the coil for injectors but it can't check clogged injectors.
It would be best if you could use an oscilloscope and check pulses at injectors and ignitors.
Clogged injectors can't be checked directory by the ECU but that will cause other problems such as a too big air to fuel ratio.
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Old 06-01-14, 08:54 PM
 
 
 
 
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