No Start,,Yea another one

[SupraSean]

Got everything put together hooked everything up turn key, CRANKS OVER but doesnt fire, no sputter, nothing.. narrowed it down to the injectors. i have 40psi of fuel at the rail, but the injectors are not being grounded. checked ecu grounds which are all good. Exposed a small amount of wire for each of the three wires for the injectors at the ecu, individually grounded them using the ecu ground and they all fire.. so at this point im ready to consider that the circuit for the injector ground in the ecu has fried. before i buy another ecu,im just wondering one thing. Does the power go through the injector resistor first before the ecu? or visa versa? im just wondering if that could possibly be bad. Thanks in advance btw its a 92 gte

 

[SupraSean]

ok so bump on this thread,, new ecu.. still nothing. What actually commands the ecu to fire the injectors? any help with this situation would be awesome Thanks in advance

 

[hvyman]

Does it crank ok?

 

[Nick M]

Got everything put together hooked everything up turn key nothing.. narrowed it down to the injectors.

The injectors don't crank the engine. The starter does. The injectors will not pulse without an airflow meter signal from running, or the starter crank signal. I think you left a ton of information from your original post. Pull codes if your engine cranks over but doesn't start.

 

[kueves87]

check that you grounded the ignition coils, i'm pretty sure they wont fire if not grounded.

 

[SupraSean]

Ok,, i screwed up how i wrote this, let me clarify,, it does crank, and it is definately in time and i definately have spark. If you spray starting fluid it will run.going to try to do a noid light test on the injectors this weekend.Oh,, and no codes

 

[bioskyline]

bad resistor box for the injectors?

 

[Nick M]

and it is definately in time and i definately have spark.

You really need to look at the fuel pump/circuit, and make sure you have power to the injectors. The ECU supplies the ground which it seems you know. I doubt you lost all the grounds independently.

 

[SupraSean]

Ok,, ill check that out.. None of this makes anysense since i havent done anything different with the harness. lol.. Thanks for a advice so far guys ill try to do some diag this weekend if this heat lets up a little (-95), and is the resistor box for the injectors right next to the fp relay on the pass side strut tower?

 

[Nick M]

Does the fuel pump run? FP to B+ in the diagnostic box.

 

[SupraSean]

yes it runs,, like i said it builds 40 psi of fuel at the rail. but after you stop cranking the psi drops. which doesnt seem right to me i would think it should still hold pressure right? maybe bleeding through the injectors into the cyl? no idea

 

[89supracrazy]

Did you try these links.

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=59


http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=51

The E01 and E02 grounds hook to the intake maifold. Make sure you have them connected good. Follow the other link to make sure you have voltage between the NO.10,20,and 30 to E01 and E02. Also check your 7.5 fuse in the link I sent you. You said you got everything put back together, would did you actually do.

 

[Nick M]

yes it runs,, like i said it builds 40 psi of fuel at the rail. but after you stop cranking the psi drops. which doesnt seem right to me i would think it should still hold pressure right? maybe bleeding through the injectors into the cyl? no idea

When cranking the starter signal powers the fuel pump. You need rpm to run the pump after cranking as a safety measure. If you drop right after cranking, that is likely the problem. Well, the starter doesn't power the pump, it just allows it to be powered.

 

[SupraSean]

Did you try these links.

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=59


http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=FI&P=51

The E01 and E02 grounds hook to the intake maifold. Make sure you have them connected good. Follow the other link to make sure you have voltage between the NO.10,20,and 30 to E01 and E02. Also check your 7.5 fuse in the link I sent you. You said you got everything put back together, would did you actually do.

My computer is being anti helpful as of now and wont let me go to the linked pages. i assume you mean What did i do.. I put another gte in my car used the same harness that ran perfectly fine previously. nothing has really changed i was going to be setting up the map ecu 2 but i have it disconnected to eliminate one more possibility of problems... ok so i probed the injectors today(which btw are rc 550s with ev2 clips). here are my results.
Clips unplugged:
cyl 1 12volts/roughly 1.5 volts
cyl 2 12volts/-0.2(roughly)
cyl 3 12volts/0
cyl's 4,5,6 were the same for their corresponding circuit.

Plugged in and back probed i have 12 volts on both sides of all injectors, when i crank it over the voltage has the normal drop to around 10-10.5 volts, but i dont see a (Neutral) number signifying a pulse.
The next step im ready to try is one Recheck for the 3rd time the manifold ground lol,, and then check the injector resistor to see what kind of numbers its getting. Which btw i tried another injector resistor to no avail.

Side note: The diagram i have infront of me right now is from mitchell, it shows the blk-org wire which i assume is the power, it shows it going to one of the wires for the ignition coil??

Need help guys Thanks

 

[89supracrazy]

If it was me I would start at the cps and check the resistance on the coils. The ne sets the igniton and the g1 and the g2 sensor sets which injector to fire. If the ecu don't see the signals it will not start.

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=IG&P=16

 

[SupraSean]

Ok i will try that. the only problem i have with that, is that it was the same one that came off of my engine when it was running. but it could very well be possible.Thank you, ill check that tonight

 

[Nick M]

You said you lost fuel pressure when you stopped cranking. You went from what to what? After cranking and starting, you will have an input from the CPS. The computer then switches to the low speed operation of the pump. I don't know how the MAP ECU runs. I would think it only takes away the airflow meter signal and translates the map sensor for the airflow meter. What all does it do?

If you have spark, you have to have injection duration unless you lost all your grounds independently. Or the pump operation is lost after cranking which would be the two speed circuit open in some way.. Those are the only real choices. If you have spark, it can't be the CPS.

 

[SupraSean]

Map ecu is NOT connected. i think the fp issue is not interrelated. and wouldnt it be possible to only have one contact point, say g1 go bad?

 

[89supracrazy]

Ok I was in a hurry this morning. Had to go to work. That last reply I wrote was off the top of my head. I was pretty close. The fuel injectors will not work if you lose either the ne or g signals. Here is the link to prove it. Scroll down to page 15 and read. I would also check the cps connector which are brittle and the wires break right off.


http://www.cygnusx1.net/Media/Supra/Library/ToyotaTech/h22.pdf

 

[jetjock]

...If you spray starting fluid it will run...