Outer Limits 4x4 Board

hey fellas ive got a 1990 turbo diesel 2.4 hilux surf and is hard to start cold. im assuming it has bad glow plugs how do i check. ive checked the power supply and there it power so would this indicate a glow plug problem? how can i be certain before replacing them. cheers

Hi mate run a wire from the positive on the battery and touch the top of the glow plug, and if it sparks they are still active if no spark they are no good.
Also l would replace all glow plugs even thou maybe one has bit the dirt, as it takes away any probs in the future.

Cheers Chris