4age Silvertop wiring issue Options

[lagos]

I've been helping blackscarlet get her swap running at it seems we ran into a wiring related issue and the car will not start. The harness was original done by DrTweak many years ago but the swap was never completed and the car sat for a while. Maybe a few 4age gurus on here can point us in the right direction.

Here are the issues.
1. the car will not crank
2. the srs warning light is behaving oddly and staying on even after the key is out of the ignition.

I feel like there is a grounding issue going on here. On the 3sgte there is normally a ground wire from the main harness to the back of the intake manifold that provides a ground for the injectors and a few other things in the EFI circuit. I had blacscarlet take a look under the car but she couldn't find any grounding wires on the back of the 4age intake manifold ... is it located elsewhere or handled differently on this engine? I don't have a proper wiring diagram for this motor, just the ones for the car.

The cranking issue could be caused by an alarm that is installed. Figuring this, I bypassed the starter relay and supplied my own 12v to engage the starter. The engine cranked without problems but would not fire.
Next I tested to see if we had spark, and it seems that we do not.
I went on to test the injector harness clips for power, and they did indeed have it, along with the main power wire that feeds power to the coil.

I still feel like this is a grounding issue due to the odd srs behavior, or in the worst case, a problem with the wiring harness conversion.

Anyone got an idea as to what could be going on?

[lagos]

As for the lack of spark. What igniter are you running? If you don't have the original Silvertop igniter, you can run a 201 igniter from a 4Runner.

I'm not sure and will have to check (its not my car, just someones that I'm helping), but from my personal experience an incorrect igniter wouldn't prevent the car from starting. The car would still start but have trouble reving over 5k or so.

Grounds. make sure the engine is also properly grounded to the chassis.

There is one main ground on the engine harness that provides the ground for the ECU

, and the necessary sensors that need it...injectors are not one of them. Injectors have a power source, and a signal wire. No ground wires.

Where is this ecu ground located? On the 3s this ground is at the back of the intake manifold but it doesn't seem to be the case on the silvertop.

SRS light....have you removed your steering wheel at all, with the clock spring? typically, the SRS light will stay on if the clockspring in the steering wheel is bad, or if one of the sensors on the front of the car used to indicate an impact and blow the airbag has been tampered with.

The factory wheel and clock spring are all in place. The srs light behaves strangely, staying on even when the ignition is off. I have seen this on a few swaps before and its always been related to a wiring or grounding issue.

Lack of starting. remove, or disable your car alarm completely and see if that changes anything. This is a very common problem on Supras and SC's with their factory alarms when a swap is done.

The alarm could very well be the cause of lack of cranking, but it shouldn't affect the actual starting of the vehicle if the starter is engaged manually. I did remove the alarm and bypassed the starter relay but still had no spark.