Sounds as though the PO installed a Msource kit with monark glowplugs...bad one should use bosch 80035's.....

There should be an odd switch somewhere in the car you hold on to preglow the glow plugs....

If the car still starts with out holding that switch in....then that means the PO didn't unhook the factory glowplug relay....

With out photos of the wiring, engine compartment etc.....I can't state if it was or not....

A 79 usually means it was built in 78 thus has the glow plug relay under the dash but if it was built in 79 it may have the three legged plug under the car...

This might help..


Homemade: Loop to pencil style glow plug conversion

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