brad11140

iTrader: (3)

OK help me out with this because maybe I am thinking in old world terms here as far as the way distributors work, if your timing is off than your going to spark to early or to late but your still going to spark. Now I don't know this for absolute sure, now you have me thinking, but does the ECU signal a spark based on something else other than rotor position.

brad11140

iTrader: (3)

JJust looked at the FSM and by golly BartleDoo I think you got me. ECU takes inputs from both cam position sensors and the engine speed sensor and outputs directly to the coil. My apologies.

1WILLY1

iTrader: (9)

i will be perfectly honest with you---im not 100% sure.

I can tell you this------my car sc400 1uz once was not working ----wouldnt start sometimes and would randomly stall-----turned out to be a loose cam sensor plug.


these sc's are quite advanced---and if the ecu detects some problem---maybe it doesnt send spark at all

hopefully someone more knowledgable than me chimes in to confirm


good luck

1jzchris

if you can try your ECU in another SC and see if it works........

TSleid

Well we hooked up all the spark plugs and two had spark. The ones that had spark were the ones that are at the top of the distributor caps. We took the caps off and seen that the contact points in the cap are corroded and the only reason the the two were getting spark is that the center contact point is direct contact with the rotating arm in the middle of the caps.

So we ordered up two new caps for $100 and hopefully that will be the solution.

BartleDoo

iTrader: (1)

You aren't talking about the top-center one on each cap are you?

TSleid

Yes it's the top-centre one on each cap that is sparking. Replaced both cap and rotors and still nothing. Fuses are all good, a few of them were corroded but now replaced.

BartleDoo

iTrader: (1)

That's where the coil power output goes. The other four are the leads to each cylinder. That would be a problem lol. I think you are running power backwards through the dist and every time it's supposed to output spark at the cylinder's lead where you have the coil power running to, you are actually inputting power to the lead and outputting power from the coil power lead thus producing a spark from the plug you have connected there.

1jzchris

Open up you ECU and look if anything looks burnt or broken in there. Might be hard to see,so you better off putting it in another SC and see is it works.