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Discussion Starter #1
I finished putting my motor and tranny back in the car last night after rebuilding the head with new valve seals, single install, and a few other things.

Tried starting the car and I get cranking but not starting. My ECU does not get any power and it seems to be a problem at the EFI relays. When I jumper the EFI Relays terminals 3 and 5 together with pieces of wire, the ECU gets power and car starts up fine (with fuel pressure quickly decreasing since it doesn't seem to supply power to the pump after cranking). Since I have a 2nd stock pump wired up on a separate connection, I can turn that on and the car runs fine.

Anyone have good knowledge on how the EFI Relays are triggered? I tested the relays and they work. The problem is that there is no trigger signal sent to the relay once the key is turned.

I checked to make sure all my grounds are firmly connected. Unfortunately I didn't pay too much attention while disconnecting the grounds. Are the 2 ring type connections coming off the negative battery terminal suppose to 1 go to the chassis and the other bolt to the block? I vaguely remeber this when I was doing the pull.

On a side note, I don't know if this is a related or separate issue, the alternator is not outputting any voltage when the car is running. I tested it by probing the big positive terminal while the car is running. Voltage just slowly drops once I remove the jumper cables.

Thanks for any help, suggestions, or ideas.
 

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Did you try testing the ignition switch? Power is sent to the switch then it is split into 2 circuits, 1 to the starter (which in your case is working) 2 goes to the ignition coils, igniter and the ECU. Perhaps you could try tapping on the ignitoin switch and also grab and gently wiggle the connector behind the dash then try to start the car. If this doesn't work then do a continuity test on the switch. If the problem is not in the switch check for continuity between the switch and the igniter and/or the ignition coils.
I'm leaving town for a few days, please post the outcome.

Good luck, Richard
 

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Discussion Starter #3
I did another long round of troubleshooting today and again came up empty. I'm still exactly where I had left it last night.

I found:

-- Ignition (where key goes) has power, and sends the proper 12V signals when the key is turned to ACC, ON, and crank

-- EFI and EFI 2 relays gets the constant 12V on prong "3", gets a good ground on prong "4" and when jumpered with a wire between 3 and 1, the ECU gets power, car starts. Except fuel pump ECU does now keep sending fuel and car eventually dies. All while tachometer remains at 0 rpm.

-- Even with car started with EFI and EFI 2 ports jumpered, and fuel pump hardwired, alternator does not output.

-- Alternator lead/output wire gets same voltage as battery. Regardless if the car is running or not.

-- Chassis grounds on the 2 front fender corners are good, going from the battery (-) to frame is good, then going to the block is good. Ground strap from head/hook to firewall is good. Grounding strap from fuel filter/tranny is good.

-- Alternator plug with the 3 wires. One gets constant 12V regardless of key position. Other 2 remains at 0V regardless of key position. I tested this on a friend's MKIV, and the constant 12V is normal in that one wire, but when the key is to the on position, the other 2 wires get 12V too. This does not happen on my car, which leads me to believe that the 2 12Vs I'm missing tell the alternator to actually output and charge the battery. Which is what I'm not getting.

-- Most everything seem to function properly. Such as dome light, dinging sound when key is inserted, (!) warning light, parking brake light, ABS light are all on when the key is at the on position w/o motor running. (Oil Pressure, check engine NOT lit unless EFI relay ports are jumpered)

Anybody have any other ideas? I think I've narrowed it down to the one thing that sends a 12V signal to the EFI relays to click over. This is what I believe the problem is. But I do not know what sends this signal. I would think that it's the key and the IG1 and IG2... but these wires seem fine at the ignition. Turning the key to different positions also result in normal behavior... all normal like radio turns on at ACC, then when turned to on the HVAC panel lights up/certain non-ecu controlled warning lights come on, then when turned to crank, car cranks, and I think the fuel pump primes.

I'm guessing this same wire that triggers the EFI relays to is/are also responsible to turn the 2 other wires on the alternator plug on to 12V. This I assume will "turn on" the alternator and let it output.

I'm also guessing the thing responsible for triggering the EFI relays, and alternator, is also responsible to keep the fuel pump ECU going and sending fuel.

I've studied the entire electrical manual twice over, checked the ground an infinate amount of times, checked many of the electrical connectors.... still no resolution.....

Can anyone tell me how the EFI relays get triggered to turn on? Or how the alternator gets triggered? This has got to be where my problem lies. And I'm thinking it must have to do with, or is close to the areas where I had to go to to pull the motor/tranny a week back.

Thanks,
 

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There are 2 brown wires that are supposed to attach to a ground on the front side of the intake manifold. Can you verify that they are attached? They tie into the IG2 circuit from the ignition switch pin3. With these 2 grounds the car will crank but not start. No signal to ECM or ignition coils or ignitor or alternator.
 

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Discussion Starter #6
Lonestar Dawg said:
Any luck this afternoon?
Actually, yes.

At about 1am 2 mornings ago, Lance on the MKIV list emailed something about that being a symptom of IG1 and IG2 not being in synch.

He also added that there was a large orange plug behind the TRAC ECU area that is hard to press in all the way.

Well apparently that plug I had it pressed in half way, it even made a "click" nose, but not in ALL the way.. (another click noise).

Thats all.

Feel extra dumb now. But hey.. I got really good practice at taking everything apart and putting it back on again..
 
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