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So I'm in the middle of my rb25 into a Cefiro conversion and long story short the bloke before me had a Rb25 already in the car but it blew up. I bought the car put new Rb25 in, the car started, timing belt broke killed a piston and head fixed the engine ready to go again and now it wont fire? Car has good compression.

The car cranks fine, it has twin 044 fuel pumps and there both coming on, made sure fuel lines weren't on backwards coil packs have loads of power. It definitely is a fuel problem. Injectors have constant power when I earth them out they click. Put a noid light in and nothing. If I turn the CAS by hand they click and so does the coil packs but the weird thing is if I turn the CAS really slow the noid light comes on but fast it doesn't do anything and when cranking doesn't do anything? When I do turn it slow the light flashes I wait a second and can hear something click under the plenum (only thing under there is the aacv and the weird solenoid thing) then turn it again It flashes again If I don't wait for the click it wont flash...

I've swapped the injectors out for another set I've swapped the CAS out I've tried another injector loom, the only time the car has started is when I swapped the injectors the excess fuel in the rail seeped into the bores and the car started until it ran out of fuel.

I don't think its a f**ked ECU as the car did start before and it did try and start today, problem is I cant see any L.E.D light on the bottom that people talk about and I cant enter diagnostic mode as its a conversion the Cefiro's don't have the plug that your supposed to bridge to enter it... It is a single light rb25 ecu but it doesn't light up? Pulled the cover off cant see anything burnt in there cant see why it would be cooked as nothing has been shorted out.

The only things that are different from the first time is that I put a FFP on and haven't extended the purple plug on the aacv yet as I thought it was useless? I had to extend the AFM wiring so I could put it in the intercooler piping not the turbo intake (as apparently this is better) and the aacv air in pipe isn't hooked up yet (Australia post let me down didn't get my silicone on time) but all of these things should still let the car fire right? It'll just run like balls...

I don't know where else to look now, I'm pretty sure its not a broken wire as it would be pretty unlikely to break every single injector earth wire, the only other thing is pin43 (start signal wire) has been cut but it was cut before and still ran and apparently only helps with cold start...

any help would be appreciated!

thanks!

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its definitely something not telling the injectors to pulse but I don't know what, as all the body relays are clicking they have constant 12v and I can make them click, when I crank the engine I can hear them click as well but when I look in the bores there pretty dry cant see any spray coming out... but that's whats got me stumped as when I turn the CAS by hand everything clicks but it doesn't make the noid light come on, so is that they havnt got enough power coming to them???

they all look pretty good, the main ones are the one that's on the plenum near the water neck, then the earth strap one and the fuse box one, then they all seem to come to a brown clip next to the ECU. What actually grounds the ECU, pin number 60 or whatever? I still don't understand how the noid light doesn't come on under cranking but does come on when turning by hand? As if its coming on by hand doesn't that mean the ECU has to be connecting the earths?

I just put another hose from my fuel reg into a bottle and in two key on prime ups it filled up a large dare ice coffee bottle 3/4, does this seem like too much? maybe the regs f*ked and not holding pressure enough, still doesn't explain the injectors not pulsing properly...

If you've changed the plenum and havent pluged in the AAC then why dont you fix that and see how it goes?

Have you tried pulling out a coilpack and sitting a spark plug in it and seeing if it actually sparks when you turn the CAS?

If it will spark then you will assume there is enough spark there to at least start and idle the car.

EDIT: For some reason I thought this was about no spark. I'll leave my post here anyway as it might help

Edited by 89CAL

Yeah during this I went and plugged in all the clips on the aacv still nothing. Coil packs have heaps of spark there making an arc like 3cm long can hear them all going off as well. It really seems to have something to do with when I spin the CAS by hand, I'm talking quarter of a spin hear a click noid light comes on, makes another click spin the CAS light comes on again. As soon as I try and spin it at some kind of continuous speed the light comes on once then not again but I can hear all the jecies clicking away. It makes no sense as I haven't really changed anything.

The click is coming from under the plenum I can hear it echo through it but the only thing there is my knock sensors, aacv, that solenoid thing underneath (which isn't hooked up yet but its on some kind of timed relay, that isn't controlled by the ECU and people just delete it in general) and an oil pressure sender and starter motor. So I dkno if the click is just a start up thing of the aacv to help get the engine going and every time I stop spinning the CAS it thinks the engine is off and everything resets???

ill take a video tomorrow as its hard to explain but its too dark atm..

ok so how do I test for this besides getting another one? I cut open almost the whole engine loom today to see if there is a split wire or something but no luck...

how do I tell if the ECU is f**ked? There's no light coming on but there's power coming into the ECU and that ECCS relay. I tried twisting the screw inside to the right to see if the flashes would show up but nothing.. would be really helpful if I could get that diagnostic mode to help!

would the coil packs fire if the ECU was dead?

Edited by Franko07

so I think I found the problem when I bought my car it had already had the wiring converted from rb20 to 25 turns out someone thought they were handy and soldered my CAS wires together by putting them inside straws and Aralditing them together wtf? never seen anything like it! so that's why the noid light was only coming on sometimes as when I was turning the CAS it was just by chance me wiggling the wires they would connect.

so she starts now, thanks for the suggestions!

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