hornbm

Well, I was having problems with my S5 wiring in my GS and I couldn't figure out what the deal was. I was talking about this in the second gen section but the problem now relates to the first gen wiring rather than the second gen.

My inital problem was that when cranking over the engine I wasnt getting any spark. I originally thought that this might be because I didnt have some of the fuel components hooked up to the ECU and it was spazing out. Well I wiried taht all up and no luck.

For everybody who knows how FC ignition works just skip the next paragraph.

Also for all of you who dont know how FC ignition works, the ignition system is far different than ours. The way it works is that instead of the distruibutor, in its place is something called a crank angle sensor, which sends a signal to the ECU which then in turn sends a signal to the proper ignitor to fire.

Anyway, I pulled out the crank angle sensor and put a screw driver in one of the plug wires then turned the gear on the crank angle sensor and suprisingly I got spark. Confused, I put the CAS back in the engine but I forgot to turn the ignition switch off, I was pulling to the pulley so I could align the timing and a spark flew and the motor kicked and I almost got my hand caught in a pulley.

So I went to check the EGI voltage when the enigne was cranking, and while it was at 12volts when the ignition was in the on position, when I turned it to start, the voltage droped below 1 volt. And the same voltage registered everywhere, at the coils at the relay, everywhere.

So theres my problem, How can I get more voltage to the EGI circuit while I'm cranking?

fatboy7

hmm...... sounds like the wire from the battery to the starter could be bad. The fact that you are essentialy losing all power when you put the car in start may mean otherwise.... Did you do anything with the ignition switch in your re-wiring?

Remember also that batteries don't like to just sit. I don't know how long your battery has been disconected, but if its sat more than a month or two it may be low. If you have a battery charger, charge the battery. Of course even if the battery is low, it should still be able to produce 6V-8V when cranking.

rotor vs. piston

Look for a bad battery cable and very importantly a very good ground. Your problem sounds like a ground problem. See if your battery voltage drops when you turn on the lights or other misc. stuff and if the voltage does drop you have a bad (one or more of the following listed from cheapest to fix and the most likely problem)ground, cable, battery. Good Luck.

hornbm

Well, when I was cranking the thing over, I had a battery charger connected to it to give it that extra kick.

As far as modifying the ignition switch during my wiring, I did. But I dont think it should be enough to make a difference.

What I did was, connect a wire to the on terminal of the ignition switch to the main relay to activate the relay when the key is in the on position.

I also moved the starter terminal wire from the old ecu plug to the new one.

And lastly I connected a wire from the allways on terminal to my ecu for the battery backup terminal.

Rotor VS Piston, what type of grounds are we talking about here? Where should they be added? My negative cable on my car is fairly old and could use replaceing if that makes any difference. But my voltameter in the dash only drops like 2 volts at the most when I'm cranking. Where would I need to add grounds to?

There are 5 grounds on my ECU harness 2 possibly three of them are questionable. The first questionable one is just grounded to the metal frame of the dash, the next it grounded next to the flasher cpu and the last questionable one is grounded on my intake manifold. The other two are on my radiator housing and on the engine block itself.

Now that I think about it these probably arent the best grounds in the world, but what should be, and how do I know? I not really familiar with exactly how grounding works, just I know it has to be there. Could someone explain this to me so I know where would be best to put the grounds?

How would bad grounds cause low voltage while cranking yet it works fine when its in the on position? Again I really dont understand how grounding works.

hornbm

someone in the second gen forum mentioned that I might have the trigger for the main relay wired to IG2 instead of IG1 on my ignition switch, how do I tell which terminal is which?

(I'll check the wiring tomorrow, but if someone could just tell me which color wire it is, that would save me a bunch of headaches before I can get to my car tomorrow.)

fatboy7

Yea, the IGN2 thing would do that as well.

hornbm

THAT WAS IT!!!

I just tried it and my moptor fired up but then dies immediately, and I have coolant leaks to figure out and timing, but otherwise thanks guys!