Daddy0

Looking for knowledgeable advice. I'm fairly new here so please forgive my ignorance in advance:

My son and I have swapped a 2JZ-GE from a 1996 SC300 into a 1990 Mazda RX7 (drift car), and had the car running for a few weeks but after installing a fan controller we heated the car up to see if the fan would come on at the right temp, the radiator hose blew off and after we shut it down and put the rad hose back on it will crank, has spark and fuel but will not fire. I think it is flooded, but even disconnecting the fuel pump and cranking I can't get combustion. It has been suggested to me that the injector driver in my ECU may be bad, and that I may need to replace my ECU. If so, what ECU can I use? The ECU I have is not the original motor ECU, and the motor always ran rich and did not idle well. Is my motor OBD1 or OBD2? does this matter for selecting an ECU? I was told any 2JZ ECU would work as long as it wasn't vvti. Any help/advice would be appreciated.

thanks,
Daddy0

Ali SC3

iTrader: (10)

you have one of the odd years of ecu, 1996 was ob2 but not vvti. so maybe you can use one from a 97 as vvti was not introduced until 98.

easiest way to tell, is to look at your maf sensor.
If you have a boxy metal maf, its a karman maf and its odb1.
If you have a round black plastic maf, its a hotwire maf and you are odb2

Try taking out a few of the plugs and inspecting them, if they are soaked in fuel, you may want to take them out and dry them off.

Daddy0

Thanks for the info sir!

Ali SC3

iTrader: (10)

the mafs on odb1 and odb2 are very different, and most of the ecu's floating around are odb1, which would not work very well with your setup. You should still be able to find a 96 or 97 ecu, is it an automatic and what is the part number on the ecu you are using right now?

vangb2

iTrader: (2)

If you have that much pressure, maybe your head gasket went out.

Ali SC3

iTrader: (10)

it is possible depending on how hot you got it, you may want to compression test it.

Daddy0

A little update:

I changed plugs which were pretty fouled from running rich, and the car started up fine but is still clearly running rich. I have another ECU on the way from a 96 automatic. I did not get the original ECU when I bought the motor. The ECU I have been using is from a 94. I am told that the auto and MT ECU are different slightly but will both work, is this true? I used an auto motor but put a W58 on it, and jumpered the NSS. I have been told that my ECU is probably bad, possibly a bad injector driver. I am sure of this; the fuel mix has never been right since I got it running, it has always run rich and blown some pretty foul exhaust fumes. When I had the throttle body off to change the plugs, I saw that there is a lot of black carbon build up in the intake from the throttle body back. I don't think that the head gasket is blown because the oil looks to be un-contaminated.
I guess I'll know more when I put the different ECU in it.

Thoughts?

Oh, by the way the MAF is OBD2 style, I tried an older MAF and the electrical connectors were not compatible.

Ali SC3

iTrader: (10)

yeah you are using the wrong ecu. you have an odb2 maf and an odb2 engine harness it seems.
Im surprised the car starts at all, does it throw any check engine light?

you need to change the ecu, or change the harness and maf. the new ecu should help out alot.
the odb2 maf's output a voltage to the ecu to measure, the odb1's output frequency.
an odb1 ecu with an odb2 maf will read never run properly.
the new ecu should take care of the problem. good luck.

99SC42

iTrader: (44)

LOl i went through the same BS, when i was selling my red SC.
The car itself is 93 SC400, i put a 9SC300 engine and harness on it, first it wouldnt run then i got it to run, no it' running rich i have gas coming out of the tailpipe.

I then realise the 96-97 SC300 have (3) O2 sensor (2) on the manifold and 1 after the cat, installed that sensor and replace the cat to the 96-96 cat problem fix.

Now it stalls and fall right on the face once you rev the engine up once the rpms drops the idle is all over the place, i replace tps 3 times i went through the whole thing, replace the maf sensor, ecus i had 5different 2jzge ecu from different years, and maf sensor still ran like crap.

Finally pulled the exhaust manifolds off and replaced them with 92-93 manifolds which is the one with bolt on style o2 sensors, replaced the maf with a 92sc300 maf , engine harness and ECU .
Problem Solved , I spent over 3months working on it trying to figure the things out, so when i hear people say *oh it's the same * no it's not the same If you have a 96 engine get a 96 ecu and harness , maf sensor and exhaust manifold with midpipe (secondary cat with bolt on sensor)

And the problem is on the 96-97 ecu you can just jump E1 with t1 to pull the code, because it will not work i tried it .
So for me to pull the codes through the obd2 port i will need to replace the dash harness to a 96-97 and i didn't fell like doing that.

Ali it will start but will run like *****

gl

Ali SC3

iTrader: (10)

wow, is that what the issue was, thats some complicated stuff going on.
But yeah, interchanging years too much is never good, match the ecu, engine harness, engine, and sensors to avoid all these issues. Sounds like the OP will not be able to pull codes either unless you install a 96 sc3 dash harness, or have an odb2 rx7 dash harness and somehow integrate them, which sounds like a pain.
If you have an odb1 rx7, you shouldn't need to get the cel working anyways, so its not a big deal to leave it.

Daddy0

Yeah, no CEL for me, RX7 dash is pretty much an empty shell. I don't have the harness for the 3rd o2 sensor either, but understand that only the 2 on the exhaust will suffice. *fingers crossed*
This swap was my first real major swap and I did my own harness, mounts, etc. Learned a LOT and so did my son. I'll post here after the ECU swap and let ya know if it helped. Otherwise I guess it's a stand-alone aftermarket ECU. i hope not, that's a lot of money and a lot more to learn.

99SC42

iTrader: (44)

You need the 3rd sensor that's under the car with that cat converter if you wanna use the obd2 stuff.Trust me i have been there i finally got everything scared away 4weeks ago!

You are not getting a cell because it's not wired into your cluster..or whatever the case maybe.

It's a pita man, i will never do it again lol, I spend over 100 hours on this car 12-13hours on saturdays /and sundays.

I just hope you get it working.

Daddy0

Yeah, i didn't even know that there was a 3rd o2 sensor until I got the header and pipe and there was a bung in the pipe. I'll look at the diagram and see what I can do for the 3rd sensor. Cats are gone, using header and mid pipe.

Daddy0

ok, correct ecu=running well now, just inconsistent idle a bit but not a major problem. maybe IACV?

Daddy0

running good now. Thanks for the help guys