UZZ31 1UZ won't fire. What have I missed?

[cjsupra90]

Sideshow, I agree with you 100% but the test proved it for one plus a good friend of mine works for a lexus dealership here as a tech and he never heard of this either but he ask his head master tech at the dealership about it, and he instantly said yeah the whole problem is the 92 ecu needs the cold start to run.. We tried this on the 93 SC that we check the ECU in and sure enough when the car was cold it would not start with the cold start un hooked, but when it was cold and we jumped the CTS leads (THW and E2) with the resistor, it started right up...

I dont know if this is only a US thing maybe or a SC thing or what... But the head master tech at the local Lexus dealership seemed to know about it.... Im actually going to try to get him to actually explain the system function in more detail if he can and see if he knows why toyota did this, cause like you, I have not seen another toyota set up that acts this way...

 

[cjsupra90]

cuh8er just for the heck of it, try what i did with jumping the coolant temp leads with a resistor in place of the sensor. What your describing sounds almost identical to what the car that I was dealing with about a month ago as doing. It would fire over like you said "a couple RPM's and thats it... The only difference that Im seeing is you have the cold start pluged in where as the setup that I was dealing with didn't have a cold start injector to begin with... Again, just for the heck of it, try the resistor test and see if it will fire and run...

 

[sideshow]

i think he doesnt really know how to test things

u can also try getting long screw driver

put pointy end on injecotr body

put handle end on yr ear

get someone to crank it and u should hear clicks
so basically use screwdriver like a stethoscope

anyway check the basics first like i said

anyway ill ive helped enough
off to the nats
ill come back in 2 months see how u went

if u get stuck i have a help desk over the phone
2 bucks a minute


heheheh

 

[cuh8er]

Lads,
ALL injectors were gummed up.
I drove the injectors from the ECU plug and after a while they came good.
Idles nice, and throws no codes so I think it's good to go, although I wont be able to drive it for a month or so as there is other stuff to sort. Time will tell if there is no other issues.

Sideshow, one more thing before you go, I should be able to leave the auto stuff alone shouldn't I? No need to 'trick' the ECU at all? Going by your other posts there is no need to play with it at all?

Thanks guys for the help, nothing compares to the feeling when you're scratching your head trying to figure something out, and then bang, it's all sorted.

Cheers

 

[sideshow]

yes u can cut the auto stuff off just make sure the wires dont touch

just cut the nsw wire right at the ecu so make sure no signal goes to the nsw wire
just have 12vs when cranking to the sta wire

 

[Cobra]

Might be worth it to have the injectors properly serviced.

 

[smokey13]

Ok, this is what I have done so far.
* +12V wired to pin E9-33 (BATT)
* Pin E9-24 (M-REL) drives the Main EFI Relay.
* E9-31 (+B) and E9-32 (+B1) both get 12volts when the Main EFI Relay is switched.
* Main EFI Relay appears to be working fine.
* Pin E10-4 (E11) is grounded.
* Pin E10-65 (E2) is grounded.
* Pin E10-79 (E02) is grounded.
* Pin E10-80 (E01) is grounded.
* Pin E10-77 (STA) gets a 12volt input from starter relay when the engine is cranking.
* Pin E9-1 (IGSW) gets a switched 12volts from the ignition switch.

i have followed this to the letter and it works. the problem i have is when i turn the key off it stays running until i pull Pin E9-24 out. this is what im using as a guide.

i know this isnt for my ECU but i used it to wire up my relays

 

[madmont]

Does your alternator warning light come on when you turn off the ignition?
If so it will supply enough power to run the ecu and all you have to do to fix it is fit a diode in the circuit.

 

[sideshow]

you should not have to do that on 1uz alternators
as they have an ign wire which turns them on
one the ign wire looses power it should turn alt off
the diode trick is usually only on older alternators with only 2 wires not 3

anyway its either ecu wired up wrong igsw wire
or efi relay not wired right
or bad earth as this will cause feedback

remove alt belt and if it still doesnt turn off then its not yr alt

 

[madmont]

I have a three wire alternator in an older vehicle and it needs a diode.
To test you could also take out the warning light.

 

[sideshow]

strange
ive never had any prob in over 60 or 70 vehicles
u must have feedback thru a relay or the charge globe might not be enough
but even then the alt should still turn car off even with globe was no there
i would make sure the black wire is ign not batt
could be also a faulty alternator

but 99% of the time its the wiring

 

[smokey13]

no belt on the motor so alt not turning, no waring light hooked up.
do i even need E9-24?
(M-REL) drives the Main EFI Relay, i have this hooked to the ignition switch and everything works fine

 

[smokey13]

ok just relooked my stuff over this might be it, the relay i have running my igniters and injector is running off pin 24 too is this the problem

 

[smokey13]

any help on this

 

[sideshow]

i never run injectors or ignitors of a relay

the ecu has 2 power systems
one is efi relay
other is power to inj/coils/ignitors all one wire never connect this to a relay
toyotas mostly run this power direct from the key
if u have all powers running thru a relay then if the rest fo yr wiring is not up to spec then this can happen

run the blakc/orange direct to ign 12v directly on yr key
or find the power that powered up yr orig coil and connect it to that wire