oldManTan

i have a 92 SC400 that i bought not starting. The entire ignition system is new, it has fuel, and i checked the igniters they work. When i try to jump it for codes the CEL doesn't flash or do anything, it's just always solid on. i bought another rebuilt ECU and the CEL never comes on at all and seems to be even worse.
to summarize:
-cranks fine
-has fuel pressure
-igniters work
-no spark when cranking
-CEL never flashes, always solid on
-second "rebuilt" ECU does jack ****

can't be NSS because the car wouldn't crank at all then and it doesn't if i put it in D, there's a 2 wire plug that seems to be cut off right next to the firewall where the main harness comes out, anyone have any idea what that is even?

my next step will be to try to check the cam sensors and crank sensor so i'm gonna go search for write ups on that. if anyone else can chime in that'd be great.

oldManTan

checked cam and crank sensors. driver side cam was good, passenger side had some frayed wires which i resoldered with fresh wires. Crank sensor however was another story.
First off the sensor itself read 0 ohms, like it was shorted (supposed to read 900-2k or something). the wires were also hanging on by a single strand. so i cut the harness half way and soldered new wires into the plug.
my only question now is, since my wires broke off right at the plug i have no idea which color goes to which side of the plug, or if that even matters since it's just an AC signal going through? if someone could send a picture of their crank sensor that'd be great to see which color wire goes to which side. i'm gonna work on it this weekend.

oldManTan

man this forum is dead if it's not some 100 page 2jz build that never gets finished.

vipsoarer

Have you checked continuity from even he broken part of the wire to the ecu on the harness? Reason I ask is my old uz had MANY brittle wires that seemed to have either corroded and stopped working or they had a break somewhere else in the harness. Remember that a lot of the harness wraps around in multiple areas including snaking through the intake manifold. I wont be able to help much more as I no longer have a uz in the car. Fuses all good? just trying to think of the obvious stuff that are easy to test. hope that helps

LEXXIUM

iTrader: (1)

Ok my neighbor across the street had the same issue not wanting to start for a week or so, next thing I know he was driving it.
i asked him wat was the problem, he told me he replaced the crank angle sensor or some thing like that, it’s been a couple of years, he would start it and make it run for 3 seconds with a carb cleaner in the throttle body when it wouldn’t start.
the other thing I can think of is timing, other than the sensors if the spark is there and fuel gets delivered, starter engages, I’d put your old ecu back on or try another one and go from there.
Pull one of your plugs and see if there any fuel in your cylinders, just to make sure your cyl aren’t full of fuel.

oldManTan

yea i'm tyring to replace the crank sensor but the wires broke at the plug so idk which wires goes to which side now. i already soldered new wires in i just need to solder them to the harness now but don't wanna do it wrong and ruin a brand new sensor. so if someone could take a picture of their sensor that'd be great.

LEXXIUM

iTrader: (1)

I would take a pic but I don’t know if they’re the same between your 92 and my vvti.
tried googling the pic?

oldManTan

Yes i tried lol, no luck

oldManTan

big update! got the new ECU to boot up. so with the key to ON i remove the EFI fuse, wait 5 seconds, put it back in and i get CEL from the new ECU.
The car cranks, has spark for like a second and tries to sputter and then just cranks continuosly again.
i'm also able to check for codes now and i'm getting 14, ignition signal and 78 EGR failure. EGR i'm not concerned about, gonna remove it anyways, but the ignition signal i'm not sure about. Everything is tested and works. Both igniters work, both ignition coils are brand new, i'm gonna test every single spark plug wire tomorrow cz i've been at this all day basically today. Changed to brand new spark plugs today too, the old ones were covered in fuel.

oldManTan

Got the car running, it idles great, however when i give it gas it sometimes sputters and almost dies but recovers every time.

Still getting code 14, gonna do the simple stuff like check grounds, plugs, wires, and all the visual stuff. Judging from other code 14 posts, it's a pretty annoying problem and i haven't seen any resolutions.

I still have to pull EFI with the key to on, to get the car to start, so that's another issue.

oldManTan

ight i'm dumb, the stuttering was from an empty tank lol. Car runs fantastic now, revs like new everything is perfect but i'm still having the EFI issue. have to pull the EFI with the key to ON then plug it back in for the car to start. can't find any solutions online except one where a guy said he got a new ECU. i have a new ECU as well and my old ECU doesn't work at all. So keep searching i will.