Someone does. Seemingly centuries ago, I worked for GTE ringing out huge PBX wiring harnesses. Now though, I think I have to draw on another area of experience, football, namely "Drop back ten yards and punt." ;-)
I went over ALL of the ground points on the car, disconnecting all ring lugs at each point, sanding the ring lugs with medium coarse sand paper to provide a better mechanical connection, cleaning with contact cleaner, and then after reconnecting each to their respective ground points and giving the retaining bolts a good tightening, covering each with a dielectric grease so I hopefully would never have to do that again.
The result is all ground points at the various parts of the involved circuits are no more than 0.1ohms to the engine block.
Most of the circuit involved in the Ignition ECU I could test at the connector to the ECU itself. The resistance at the connector to the Crank Position Sensor and the Engine Speed Sensor measured around 680ohms each. The Coolant Temp Sensor measured 2.2k at the ECU connector, which is about right for the ambient temperature.
The connections between the ECU and the power amps ring out as it seems they should, 0.1 - 0.2ohms as do the connections between them and the coils.
I also tested supply voltage at the amps and coils as well as the ECU itself to make sure each was getting full battery voltage with the ignition switch in the run position.
Everything tested out as it should, statically.
All bets are off though as to what may be happening when the engine it trying to crank over.
I say that because the 'B' bank circuit still stops sparking after about a second or two.
I'm not ready to give up yet though. For one thing, the Crank Position Sensor has been a problem for some time in that the connector on the ECU side which mates to the connector molded to the sensor cable is pretty well shot as is the temp sensor and the crank sensor has had to be jiggled now and again so that the car would start. Both circuits test good statically, which I've mentioned but although neither should cause only one bank's spark to fail, they need fixing anyway and I've parts on the way.
Another thing I think I should check are the connections at the various switched ignition feed points because if any of those are loose or otherwise showing a 'high' resistance, I'm thinking they could test as good statically but cause a voltage drop when the system is under load.
What do you think, worth a shot?
Worse case scenario is that I try and don't find anything and have it towed to a garage and let them deal with it but I'll have learned a LOT more about my car in any event and some of the things I've done would have cost an arm and a leg for them to do.
Tuesday, October 11th, 2011 AT 12:37 AM