Volvo Repair: 88 Volvo 740 GLE ECU, volvo 740 gle, negative battery cable

Question
Hello James,
My question to you is with my 88 GLE Volvo's ECU.  Several weeks back my Volvo started & ran fine for several days however a couple of days later the battery was dead, so I put on a full charge on the battery which is new.  After a days worth of trickle charge the charger was removed the car did not fire.  I removed the spark plugs put some gasoline in the combustion chambers & it fired right up but shut right down.  I know that this is a fuel problem.  The puel pumps are new & are in working order all fuel related compnonets have been replaced except the ECU.  After figuring this out I removed the battery cable for several days & with the cable placed back on the car started fine & ran fine.  Could the ECU be the problem with discharging the battery when not in use & not allowing fuel to be distributed into the chambers?
Any help is very much appreciated.

Douglas PANNEBAKER

Answer
Well if the battery charge is too low it could possibly not start because of that.  It isn't uncommon.  As far as what is discharging the battery, you'll need to do a parasitic drain test after you've determined the battery and altenator are both good.  To do a parasitic drain test, you'll need to have an ammeter.  Hook one lead up to the negative battery cable, and one to the battery terminal (battery terminal must be disconnected first).  After a period of time (usually a couple hours) it should not be consuming more than 250 milliamps.  If its more than that, you have some elctronic device staying alive when you shouldn't and you'll have to find it.   Possibly the ECU.  If none of those options pan out then I'd get a shop to look at it.  Could be a much deeper problem.Hope this helps.

James