ashes2wake

Here's the quick story...

Put a low mileage motor and rebuilt transmission in my 96 sc400. Everything is installed as of this past Friday night. Go to fire it up and engine cranks great but wont fire. So I checked the basics; I have spark and fuel, triple checked all electrical connections on engine and ECU, found a loose connection. Engine cranks, fires and somewhat runs now. Has a good misfire/idle hesitation. Next i checked was ignition system components although coils/spark plugs/wires are all brand new. Everything is good including cam and crank sensors. So I pulled plugs and cleaned the fuel off from cranking it. Also bypassed fuel pump ECU. It runs but smells like fuel from the exhaust and when you push accelerator pedal it seems to bog down and will die out. I'm thinking of tracking down another IACV now. I used the one that came with my replacement motor and the old one has appeared to have grown legs and has disappeared. On a good note the engine sounds healthy otherwise with no troubling noises. So what do you guys think? Get another IACV? I tested the resistance on it so far which was about 15 ohms too high from what specifications online I found said. Probably remove it and apply voltage next.

cali108

iTrader: (1)

did you figure this out? having the same problem wont rev past 4K, smell like gas, horrible gas mileage, can barley drive it!

ashes2wake

Not yet. Still eliminating possible causes. I just wanna drive it dammit!

1JZPWRD

iTrader: (59)

I also would check both igniters that are mounted on the driver strut tower.

GroHZ30

have to checked your fuel pump? maybe it failing at some point, my sc400's was working but it was the factory fuel pump so it was deteriorating... had to clean the gas tank good thing its an easy job not like the mr2's.
also check for the EFI relay it causes idle and fuel issues.

ashes2wake

Thanks for the advice! I'll check those tonight

I havent checked the fuel pump itself yet, but the exhaust smells like its dumping fuel and there is pressure when loosening the banjo on the rail

GroHZ30

ok might as well check the fuel filter. Also if not replaced do the rotors and caps and clean your current IACV and EGR. The worse thing in here would be a failing ECU, try to reset it if not done and leave this to the last thing in the list unless you can get one fast and cheap or access to one just to make sure yours good.

Ali SC3

iTrader: (10)

any check engine light?

Its not your iacv, that would improve as soon as you give it some throttle.
I know it sounds a bit out there, but I think its your new coil. one of your new coils could be bad and this has happened to members before so I would suggest checking them and not relying on the fact that they are "new", check them by unplugging the connector to one and then try and start it and see if there is a difference. no difference = bad coil. Unless they are oem, there have been many times people have just gotten new coils and they just don't work out of the box. I would start there.

ashes2wake

No check engine light. Spark at all cylinders on left bank but i will check the coils, quick test to be sure. Took a fuel sample and it looks like moisture in the tank. Removing that tomorrow

ashes2wake

I think I've found the problem. Fired it up and pulled injector clips one at a time down the left bank. 1 and 7 did not make any difference as to how it ran once pulled while 3 and 5 created a hesitation. Did it again but put a noid light on 1 and 7 and found the circuit was working just fine so I'm thinking the injectors are stuck.

V8drummer

iTrader: (5)

Is the noid light flashing or giving a solid light on the 1 and 7 injector clips?

I'm pretty sure 1 and 7 run on the same injector driver in the ECU (you can find a schematic to verify). When my ECU went out the 2 and 8 injectors were stuck wide open.

Ali SC3

iTrader: (10)

sometimes if you tap them they will clear up if they are stuck.

ashes2wake

Noid was flashing for 1, 3, 5, and 7

ashes2wake

Put new injectors in and the firing problem is now solved. Upon first startup it went to about 2k rpm for a bit, then started surging from 1-2k. When put in gear it drops to 13ish. Is this the ecu relearning itself? It has been sitting for about 10 months with no battery. Also the TRAC light is on which may have something to do with it, don't have a scan tool to check the codes yet. On a good note the engine sounds very healthy and strong.

1JZPWRD

iTrader: (59)

Thats good you figured out the problem. Thats a first that I have an injector is bad on the big bad 1UZFE. I tried to sale a set for like two years, I finally threw them away. I think the ECU will relearn itself after the first 50 or so miles. The trac light might be the 02 sensors. There are four of them, two upstream and two downstream. Is your check engine light on also?