Rad1

I've got a lexus ls400 that a month ago driving it died.... I replaced the fuel pump, it wouldn't start after that.....I removed a bolt from the injector rail gas came out...... all over, I replaced the ECU with a rebuilt one it still won't start.... I tried checking for codes but there were none..... I had to disconnect the battery for the fuel pump... any idea's if I can find out from jumping wires to get a code to find out what/if there are any codes ??? thanks

CLLEXUSS

you getting spark?

Rad1

I replaced the Crankshaft sensor today, I checked both Coils and am not getting anything from either of them...I just replaced the ECU also... any advice on where to go from here ???

JohnAndic

Scotty Kilmer car channel. Don't replace things just hoping its gonna fix it. That is how you end up spending mucho $$ for no reason.

jaaa

Even worse, you screw something else up in the process.

Sin1UZFE

If it just cranks and cranks check the battery in the key. I don't know if replacement ecus would come with new chips

Rad1

I agree on not randomly replacing things, I was told in one of my previous posts that one of the 2 things I replaced could be the cause

bradland

+1 on not throwing parts at the problem, you can go broke doing that.
If you're getting fuel there there aren't many things that can disable everything on the spark side. Crank sensor is one but don't forget the cam sensor will do it as well...

CLLEXUSS

i was wondering the same thing if maybe it's something to do somewhere with security of the vehicle, op mentioned it happened "driving it died" seems vehicle was in motion and it just died so he tackled the main usual culprits, the ecu and the crank sensor.
it's almost behaved like a fuse went ~ was working then all sudden not

Rad1

CLLEXUSS
That is EXACTLY what happened to me... it started fine, drove fine for about 3 miles then died..... I was able to get it started got 1/2 home it died again, was able to get it started again it died just as I was pulling in my driveway.... the gas gauge is not working so I thought I ran out of gas, put 5 gallons in still would not start, opened to gas flap unable to hear the fuel pump so put one of those in, still would not start, I came here and was told it could be my ECU, Crankshaft sensor, or cam shaft sensor.... I replace the ECU and crankshaft sensor still no start... MY ABS light will flash once when I jump the diagnostic connector.... check engine light does not, none of the others do either.... I was wondering about the gear shift is there a kill switch for that if you try to start it out of park ??? or would the ABS light flashing once the stay on be the problem...with the connectors unhooked is there a way to see if the ignition coils are getting any voltage ??? how can the ignition coils be checked....I think I had a care several years ago that would not start due to a bad switch in the gear shift.....

CLLEXUSS

Let me ask you this, is the replacement ecm, did it do anything different at all? Or is the car pretty much exactly the same with the new ecm?
I am guessing you have not been able to check it for spark yet then if I am reading it correctly.
How many miles on the car?
Your problem was intermittent for a short time now nothing presently. You have a pre-existing inoperable fuel gauge probably ran it plenty low many times, timing certainly isn't intermittent, either its on or off not intermittent.
I'm just trying to weed through what your stating without getting too complicated in different directions because that's easy to do.
If it were me I'd probably want to test it for spark, you can research test for spark and decide which way is the best for you, or you can research testing the coils and do that too, it's a google search. Also I might want to test the fuel pressure, verify I am getting the right pressure to the injectors, and that's a google search too there are fuel pressure testers. I mean is your gas filter severely clogged yet a a little is still getting through to the injectors not enough to start it? But anyways all these things you can test first.
There's a few main things that an engine needs to start or at least show some life, that is fuel, (proper pressure), timing (timing has to be right but timing is not intermittent, its on or off), then there's spark. Spark is pretty easy to test.
For me I would not bother thinking about the gear shift or anything like that, I'd test for spark, then I'd put a pressure gauge on the fuel line to make sure I'm getting adequate pressure. Because if you're getting the right fuel pressure, and its sparking on all cylinders when your cranking it over, that **** should be showing some kind of life Because I don't think there is an issue with your timing as the symptom was intermittent before it failed.

Rad1

It's doing the same thing before replacing the ECUcranking but not starting.... I unhooked the lead from the ignition coil at the top front of the engine put a tester between and cranked the engine, I saw nothing, no light, with that I assumed the other coil down lower would in the front would do the same thing.....As far as fuel pressure.. I can smell gas after cranking it... I also removed the front bolt off the injector rail on the passengers side, cranked a few times.... came out to see there there was gas.... it was all over... that's with just loosening it.....I think I'm not getting spark.... but am unsure where else to go, other than have it towed to the garage.....

Rad1

I checked both ignition modules @ 28 degree weather both with my Ohm meter were .99 & 1.75... are these normal ???

Mauser

What year is your car? Does it have an immobilizer? You replaced the ecu, was it virginized or did you get a master key with it?

If your car does have an immobilizer:

What does your security light do when you insert the key into the ignition? If it continues to blink your ecu does not recognize the key and you will not have spark.




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