hey guys...
have been having a little white smoke at start up. the mornings have been down to about 42 on and off here in NEPA...so i checked glow plugs with ohm meter. NO HARD START at all. i got some crazy readings though...we replaced them in may when i did new orings and valve springs. spoke to Clay about them and he said reverse the leads and the numbers were even more weird...hoping someone with more electronics experience can help...

here are the readings with the black lead from my fluke meter hooked to the ground terminal on battery and the red lead on each GP pin....
Pass side from rear to front - -.7, 5.5, -.06, -.07
Drivers side from rear to front - -.5, -.5, -.4, -.5
YES THEY WERE NEGATIVE unsure about negative resistance

here are the readings when i reversed the leads, red lead attached to ground on battery and the black used to pin out the GPs
pass side from rear to front - 1.6, 12.8 to 16.4(kept climbing everytime i checked it), 1.6, 1.6
drivers side from rear to front 2.0, 2.0, 2.1, 2.0

i cant understand the negatives when i know that is the way the meter is to be connected. but when i reversed them, the numbers grew to almost out of specs. im also concerned with the 2nd from rear pin...its positive when all others are negative and its also very large in reverse when others are small...any ideas?

the truck blows white smoke at start up in the am...temp doesnt seem to matter. in the am always wait till WTS light goes out. after work, never smokes and i also wait for WTS lite to go out. sits over nite for about 12 hrs and i drive about 15 miles and it sits for another 8 hrs.
Clay even seemed stumped...any help would be greatly appreciated as i know it will start to get incredible cold here in NEPA soon...if the rain ever stops

 

My meter will do that sometimes if I have it set to auto...even the negative terminal has some current passing through it, it is a small amount but more than the GP pin so the meter gets confused and reverses polarity. Completely normal. If you ground the black probe to the engine it should show positive resistance.

I agree. #5 has an issue. The plug may not be seated all the way on the gp...

 

thanks for the reply...
if the plug isnt seated, would the reading grow steadily as i check? also would one glow plug cause white smoke at start-up in 50+ degree weather? the smoke clears very quickly after driving for less than a minute. just trying to make sure im not struggling with cold starts in the winter and changing them out in the snow...thanks again

 

Possibly. If the plug is full of oil the readings will be weird. I would think even one non functioning glow plug would cause some smoke but it would likely be very low amounts and go away as soon as that cylinder warmed up...shouldn't take very long in those temps. Altitude has an effect as well.

 

guess i need to tear into the pass side...does the pin corrilate to the GP? like the bad one is 2nd from back, so is it the 2nd from back GP too or do the wires switch around?
thanks again...looks like a good project for tech day next weekend

 

Yes they are relative to their position in the head. At least it is the pass side...IMO that one is the easiest side to get to.