The glow plug gremlin that had me chasing my tail in Tulsa
Last Tuesday a Freightliner came in with a hard start and white smoke, cold engine. I swapped the intake heater relay first because that was throwing a code, but it still cranked slow for like 15 seconds before catching. Turned out two of the six glow plugs were drawing barely any amps, and my multimeter test looked fine until I actually did a current draw test at the harness. Has anyone else seen intermittent glow plug failures that pass resistance checks but still act up when it drops below 40 degrees?
Been there with the resistance test lying to my face, swore I was a genius until the cold start laughed at me. Glow plugs are sneaky like that, they'll ohm out fine at room temp and then ghost you at 35 degrees. Current draw at the harness is the only way to really catch 'em.