Have I broken my ECU

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tommyboyblitz
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Joined:Sat Aug 15, 2015 9:40 pm
Location:London, UK
Have I broken my ECU

Post by tommyboyblitz » Thu Mar 16, 2017 7:22 pm

Not sure if i have a wiring fault which is very plausible or have killed the ECU while messing about with wires.

First of all i can access the ecu and go through all of the options etc with no trouble, upgraded firmware etc and that side of things seems fine.7

What i am getting at the moment:

-Turn the key onto the on position and everything starts fine and sounds normal, but my fuel pump will spin up but normally turns off after 3 seconds but now its staying on constantly, i can shut it off through the ecu by inverting the output.

-I spin the engine over and it seems the sparks are firing as normal but its hard to tell, (i have coil and sparks connected and resting on the head so i can see if they are firing)

-Once i let go of the key so the ignition stays on and its no longer turning over i get a random spark every few seconds, well a double spark then a second later another double start, i can also hear my injectors firing aswell, clicking at the same time as the sparks. This will continue until i switch the engine off.

I have had night mares with coils cracking and the last time i tried to move the car it wouldn't start so had to push it where it is now, I have pulled all the wiring out for coils etc and checked what i can see but cant see anythign obvious. I had wired up a set of sequential coils and thought i had wired them correctly but i am now unsure, speaking to some of you guys it seems i have got it correct but it just doesn't look right.

The only thing i did was have it all wired up and coils connected before i made the change on the map from coils without to with amps.

Thanks
Lexus IS200 Sport with 1JZ GTE vvti

RHD
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Joined:Tue Oct 07, 2014 4:28 pm

Re: Have I broken my ECU

Post by RHD » Sun Mar 19, 2017 12:36 pm

do you have a thermo fan?... thats near the crank sensor by chance? ... or some other electrical device?.... electric motors in particular emit a lot of magnetic interference, that can be picked up by a VR sensor.

you are getting some sort of interference on the crank angle sensor and it is picking up signals when the engine is not turning so the ecu thinks it is trying to start, hence the random injector and constant fuel pump activity

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tommyboyblitz
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Joined:Sat Aug 15, 2015 9:40 pm
Location:London, UK

Re: Have I broken my ECU

Post by tommyboyblitz » Sun Mar 19, 2017 4:34 pm

I have been running like this for a year and havn't had anything change, fans etc havn't moved.. But i will check wiring to see if its getting interference from somewhere.
Lexus IS200 Sport with 1JZ GTE vvti

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tommyboyblitz
Posts:60
Joined:Sat Aug 15, 2015 9:40 pm
Location:London, UK

Re: Have I broken my ECU

Post by tommyboyblitz » Fri Mar 24, 2017 7:54 pm

I have now fixed my EMU...

I built second loom up too eliminate the one thats on which made no difference at all.

Went back to the first loom and tried a second set of coil packs which didn't work.

Pulling hair out and getting annoyed i pulled all coils and sparks out of engine and plugged them all in to see what was firing and what wasn't. They all sort of fired except 1 and they where firing badly, jumping down the spark plug rather than on the proper gap. But they all seemed to be firing in the correct order - i put these brand new sparks in a week ago and have only done 120miles on the motorway..

Fuel pump stays on, injectors and coils fire after trying to start the engine with the ignition in on position but not on.

So i went back to my original idea, ditched the wasted spark coils and used the individual coils from the old lexus ig fe engine but running in wasted spark setup instead - new set of spark plugs just to rule them out, i set them up laying on the head so i can physically see the spark.. and they all started firing when turning it over with nice normal sparks...

Put them all into the engine on the temporary loom i made the other week and the car fired up into life, seems to be working normally although need tuning as it feels laggy, but could be down to the temporary loom.

Turned it off and shut down fine, turned ignition on and fuel pump starts and stops as normal sparks dont fire randomly and everything seems to be fine, starts as should and alot less misfiring than i have had on the old wasted coils.

So moral or the story is - dont rule anything out, not even brand new spark plugs - unsure what caused the problem, i recon my old shitty coil packs with crappy spark had coked up the sparks so they wouldnt fire correctly, maybe causing the fuel pump issue also or confusing the EMU or something else.
Lexus IS200 Sport with 1JZ GTE vvti

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