glow plug ohm readings
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glow plug ohm readings
My glow plugs must be bad but before I go through the trouble of pulling them out, here is what my ohm meter showed.
drivers side front to back-.471,89.0,0,0
paseenger side front to back-4.6,0,205.0,0
Is this even possible?
Can there be values that high on some gp's and zeros on others? My engine light has come on and AE shows all gp's are throwing codes.
Any thoughts or just bite the bullet and change them out?
drivers side front to back-.471,89.0,0,0
paseenger side front to back-4.6,0,205.0,0
Is this even possible?
Can there be values that high on some gp's and zeros on others? My engine light has come on and AE shows all gp's are throwing codes.
Any thoughts or just bite the bullet and change them out?
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From: Catawissa, Pa
when you ohm them out, the first 2 and last 2 pins are for the GPs. the middles are for injectors...i think. they should have some resistance, if infinity, they are bad...just checked mine and they were all 3.1 - 3.5 ohms. not sure where the zeros are coming from...
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I had checked them in the spring and they ohm'ed within tolerance then. Not all of them were very good though and #7 had been throwing a code once in a while.
I did ohm only the outside pins which are a larger and flatter pin than the injector pins.
I did ohm only the outside pins which are a larger and flatter pin than the injector pins.
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From: Catawissa, Pa
maybe you didnt have a good ground. the GPs have some resistance, be it small, not zero though. i would make sure you have a good ground for the meter and recheck. also depending on the meter, make sure the settings are correct. meaning...Kohms, Mohms, etc. mines auto adjusting...so i dont worry about that.
good luck..let me know if you need anything
good luck..let me know if you need anything
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A resistance measurement of 0.1-2 ohms indicates a good glow plug. Also just ground staight to the battery.
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The negative lead of the tester was clipped to the negative battery terminal and all gp's were tested without moving the negative lead. I did them three different times and came up witht the same thing.
Why can't they be zero? It might help me figure out if I'm doing something wrong witht the tester.
The tester is set to auto and it's a digital but it's probably 15 years old so maybe thats a problem?
Why can't they be zero? It might help me figure out if I'm doing something wrong witht the tester.
The tester is set to auto and it's a digital but it's probably 15 years old so maybe thats a problem?
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From: Catawissa, Pa
it cant have zero resistance, because the GP has some resistance. resistance is the opposition to flow. there has to be some little resistance to the plug. usually if you have a bad ground or something it will come up as infinite resistance. check a piece of wire to see resistance...even copper wire will have a little resistance.
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Maybe I'm reading the tester wrong. The readout on the gp's that I listed as zero are reading as if the tester is just sitting without the leads touching anything. On the digital readout it shows "0.L" when touching the gp's that I said showed zero, which is the same as when the tester is on the bench without the leads touching anything. I don't think the "0.L" is actually an "L" but that's how it looks on the readout.
Edit: I also just drove it and got it warm and retested it. It showed slightly different numbers on the gp's that had showed something other than zero's before but the rest are the same.
Edit: I also just drove it and got it warm and retested it. It showed slightly different numbers on the gp's that had showed something other than zero's before but the rest are the same.
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From: Catawissa, Pa
if it was like when the ends were not touching, that is infinite resistance...yes those GPs would be bad. zero and infinity are opposites. if the leads on the meter touch each other without touching anything in between...that is zero resisitance. so you probably have a few GPs bad...sorry for the confusion....
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My fault. I didn't think about the difference between zero and what the tester says when it's just sitting there. On those gp's that I said was zero it was actually like the tester was at rest.
I have done the $.50 mod so it has to be bad gp's.
Thanks for the help and sorry for the confusion.
I have done the $.50 mod so it has to be bad gp's.
Thanks for the help and sorry for the confusion.
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My fault. I didn't think about the difference between zero and what the tester says when it's just sitting there. On those gp's that I said was zero it was actually like the tester was at rest.
I have done the $.50 mod so it has to be bad gp's.
Thanks for the help and sorry for the confusion.
I have done the $.50 mod so it has to be bad gp's.
Thanks for the help and sorry for the confusion.
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What torque wrench would you recommend? I don't have a good one and wanted to get one for the gp's and to retighten the everything while I'm under the vavle covers.