you need to put the $5 multi-meter on the ECU power / EGI relay output
and have the meter ready for when the engine shuts off
to verify the power is gone or not
if not, continue to use the meter to complete diagnosis by checking each circuit until isolated the problem
"shutting off" suddenly is likely:
1. 1 or more relays failing (replace relay indiscriminately)
2. fuel pump failing or sudden fuel filter clogging (check fuel pressure during issue)
3. fuses can be 'bad' suggest also changing fuses at 'random' (change the ones you think might be associated just for the heck of it)
4. loose wires, plugs, loose ECU connection, (check ECU plug, check ALL wires, pull on them while testing CONTINUITY with $5 meter
For #4 study factory service manual diagrams, follow the power from battery to the computer/injectors/distributor/etc... so you know instinctively which circuit gets power from where, when that power should be there, etc...
for example I believe the injectors receive a 12V constant supply (always even when car is shut off)
this and other simple 'intuitive' knowledge will aid diagnostics
make sure you
A. learn how to perform continuity tests using $5 meter
B. learn how to test for ground and voltage using $5 meter
|