1JZPWRD

iTrader: (59)

I have recently tried to swap a 1JZ in my 92 SC400. After extending the harness 18 inches, I need to check on what I have done to assure this is right, before I pull my hair out. I cant get my car to stay running. I have heard it run for only about 5-6 seconds, then die. I did notice the number 4 and number 1 cylinder has been flooding with fuel. I had to drain the crankcase three times now with fresh oil. This is how I have all of my wiring ran. Someone please chime in and explain in detail if this is right, wrong, or dont know.

I realized the SC400 gets power to the injectors, coils, and igniter different than the 300. I couldn't figure out the relay that supplies these with 12 volt power during the cranking process. This is the 3 pin plug by the black fuse box under the hood. I ran a separate relay to trigger these three items on. I triggered the relay from the IGN fuse in the driver side kick panel. It does turn on and off as it should. I pulled the factory relay for now.

The second item up is the relay for the TT fuel pump. I ran another one and triggered this one from the AEM V2 standalone as a ground source. Works as it should.

The third item up is the third relay for the standalone and IACV. I noticed the IACV was getting real warm after sitting for about an hour or so. Stayed warm until disconnected the battery. The main relay that triggered the coils, injectors, and igniter was also real hot to touch even sitting over night. This is how I bypassed it. I realized this factory relay runs the stock 02, which I dont have, the IACV, and 2 more items, which I dont use.

The fourth item is running a jumper wire form the starter relay to the black/white wire under the dash to get the car to crank. Works as it should.

All relays have a good ground, operate normal, and I am wondering if the AEM V2 modified by DM cant be used in the 400 only the 300?

With the above relays bypassing several things and such, does the factory black plug by the fuse box need to stay connected or disconnected? That might be my problem.

With me triggering the relays from the IGN fuse in the kick panel, does this lose the current during the cranking process? That is a possibility. Thus not creating the power for the coils, igniter and injectors?

How are the 1JZ injectors fired? sequential? If so, can the AEM V2 be changed to run this setup?



If anyone could chime in and give me some explanations in lamin terms that would be nice. I talked to Aaron at DM, and he says there is no way the cylinders will be filing up with gas with this unit. He told me to call AEM and see if they can email me or supply me a different base map than his unit.


If anyone would like to come here and get this troubleshooted, please PM me for further details about the cost and labor. I am willing to pay someone now, if I cant get any help on this thread. Cartmill thanks for all your help and phone calls. Post if you have thought of something else.

stockhatch

iTrader: (12)

The 1jz injectors are batch fire. Your AEM should be capable of firing them sequentially, but you would have to add 3 injector signal wires to the harness to make that happen. How many injector drivers are configured in the AEM?

Pull each injector plug and test for voltage at each pin on the connector. With the key on, you should have 12v at each pin to ground and 0v across them. Get a test light and plug it into each injector plug and make sure you get pulsing while cranking and not a steady light.

If you have a steady light or voltage ACROSS an injector plug with the key turned to RUN, you will have an injector stuck open dumping fuel.

Regarding the relays, I don't like that so much of the core harness is bypassed. I would encourage getting someone out there to look at the harness and get the factory circuits and relays working. Running a separate circuit for the fuel pump would be the one exception to this since it pulls so much power.

You should really trace out the stock relay circuits and determine what is triggering them with the key off.

1JZPWRD

iTrader: (59)

Stock hatch can I call you?

1JZPWRD

iTrader: (59)

I forgot to mention also, the way I tested the injectors was this method. Everything wired up as stated above. I turned the key to on. Left the coils and the plugs out after I used compressed air to blow the excess fuel out. I was afraid to keep using the cylinder compression to make this happen. Let dry. The only cylinder that had any fuel was the number one at this time. I left this method for about five to six minutes before I turned the key off. It had very little fuel in this cylinder. I haven't touched it since then. Does the number 1cylinder need fuel to initially crank the car? Two people say no. But it might be doing this just because the way the wiring is setup by my method or the way the AEM is currently setup.


The fuel pressure regulator is set at around 42.5 currently.

spoolxexo

iTrader: (4)

This seem to be an AEM configuration question, are you a member of aempower?

If you are not, simply joining the AEM forum will surely fix any issue you have, those guys are seriously smart over there.

stockhatch

iTrader: (12)

With the key on, engine off, you should have zero fuel dumping. If you do, you have problems. I would pull the injector plug and test it as I outlined above. If you have voltage across it, you need to find out why. I also agree that you should join the AEM forums and have someone look at your cal to see if its a configuration issue.

1JZPWRD

iTrader: (59)

I just retested the method as stated above with the fuel pump and cylinder number 1 is still loading a small amount of fuel. I also check the injectors on the wiring harness side. With the key on, they read approx 9.78 volts on each of them. The battery is reading 12.32 volts. I cant check the polarity while trying to crank. I dont have anyone here to help me.

I also joined the AEM forum, but awaiting forum to approve me to post up.

stockhatch

iTrader: (12)

They read 9.78 volts across the two pins, or each of the two pins reads 9.78 to ground?

1JZPWRD

iTrader: (59)

Each of the pins reads 11.64 to ground with the voltmeter on the injector side of the harness. The coil wiring from the black/orange wire is reading 11.85 only. The volts is slightly higher do to the battery being on trickle charge for about three hours now.

DoomLight

iTrader: (3)

i have a question. i just got this AEM last week. i decided to plug it in. the fuel pump relay wire isn't plugged in into any of the connectors. some advisement would be appreciated. i wanna plug it in and see how my car runs with it hooked up.