Hi dear friend.
how are yo?.
Im electrical technician forklift.
I have a problem with Daewoo forklift with engine GM G424FE.dual fuel.
When I starting engine engine doesn't run.

I check all of wiring and sensor everything is ok.

Just I found when ignition switch is on or starting,all sensor dosent have GND signal from SECM.
In shop manual for this model says this forklift have Delayed shutdown system.
Do you know what I should be doing for this problem?

did you get this fixed? also was any codes showing?

The P series never used an oil pressure lock out. Had one once that had a bad wire harness between the coil and distributor that caused a long crank time. I have also seen a couple now where shade tree mechanics have removed the Woodward fuel system and install an Impco system. These can be hard to start and they stall easily as the PCM no longer has any control over mixture.

Great idea, i thought the same and asked the shop tech doing the work to watch the oil light during cranking ( since its only a tier 2 truck it has an ops, not a sensor), he says the light goes out in 2-3 seconds but still no spark Running out of ideas. Problem with this truck is its an outside truck and here in the northeast were coming into freeze season. It will surely get worse.

Could it be related to oil pressure?

One additional note: if a battery charger is connected during a cold start, spark occurs right away. Charging and starting systems test ok. Seems when battery voltage drops below 10.5 during cranking , no spark happens.