Hello all. I replaced 4 of the 5 glowplugs but still have a very hard time starting the car in cold weather. Would the one " not changed " glow plug make a difference? The relay looks fine but I have a replacement that I will try tomorrow. The battery was new last year but is worn from having to crank, sometimes for minutes, before it will start. I have had the car plugged in for the past 4 hrs and am trying to jump it with my 7.3 diesel but it just cranks fast for a few seconds and then slows down. It seems to me it has to be the relay but I thought I would check here for other suggestions. Also, how long does it take the heater to warm up the engine enough to start it in cold weather? I wonder if I need a new block heater as well? Thanks. Oh yeah, it is my wife's car and she said that lately she has noticed it bogging down ( not enough power ) going up hills ( wot ) when the engine is cold. Maybe fuel filter? I need to learn more about this car. I also need a garage.

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96 F350 CC, LB, 4x4. 290,000 with around 90,000 on wvo.

82 Mercedes 300d. New to me. 211,000 soon to be on wvo.