Also was I suppose to test the glow plugs with the ignition in the on position. I tested them with the car completely off. Thanks again.

 

You should test the glow-plugs with the ignition OFF. Its highly unlikely that all of the glow-plugs are exactly 1 Ohm. I don't know what kind of a multi-meter you have, but it sounds as if you are not measuring something right.

Make sure that you are measuring resistance, and not voltage. Try the smallest OHM scale first. Touch the two probes together and see if it shows 0 Ohms. Also make sure that your multi-meter's battery is in good condition. Is this an Analog or digital meter?

Phil

 

Ok here we go. I will include a picture of me testing meter. It's a digital one, Actron to be specific. With the meter set to 200 Ohm the lowest setting with a brand new battery in it I touched the positive and negative together and it gave me 00.4. Let me know what you think. Thank you again.

David



[IMG]local://upfiles/4806/135D42C4CB8F4BB78836AA6B662A1A6B.jpg[/IMG]

 

I have two digital meters, a low end one (ie: Cheap) and a high end one. I just tried it on both of my meters and they both read Zero Ohms when I touch the probes together.

I am not comfortable with the fact that yours reads 00.4 Ohms. Go to a Radio Shack store, buy a couple of resistors having known values of less than 1 Ohm (they cost only a few cents), and measure them with your meter. You should also repeat these measurements in the store using a Radio Shack meter that you can borrow from them for a few minutes. I am sure that they will oblige. I suspect that you will find that your meter is inaccurate.


Phil

 

If I remember correctly, the 85 is the legendary 3-liter engine with all the glow-plugs connected with single rail.
Checking resistance of all plugs together is not reliable. It can give you an idea, when all the plugs are burn-out, but not much more. For glow-plug testing, you need to disconnect the rail (pain on the a**) and check each plug with control light, or check the resistance.
I would start with connecting the control light to the rail and see if the plugs are getting 12V at the start-up.
The last, but suppose to be first. Did you check the light bulb on the cluster?

 

Phil,

What do you think about this fellas response. I have returned said faulty meter and the manual tells me to check the glow plugs like you said. I will do that shortly and report back the resistance numbers.

Dave

 

Ok here are the numbers.

Glow Plug #1 0.4
Glow Plug #2 0.4
Glow Plug #3 96.4
Glow Plug #4 1.092
Glow Plug #5 .6

Tell me what you guys think. Looks like #3 and #4 should be replaced I suppose.

Dave

 

#3 and #4 should definitely be replaced, and unless the other 3 were installed more recently than the two defective ones, they will very likely also fail in the not-to-distance future.

How did you end-up measuring the resistance? What was different this time?

Just curious.

Phil

 

I returned that tester to Autozone. Then I bought one from Radio Shack. It said 0 when I tested the two probes by placing them together. I was also not grounding the negative lead correctly. I grounded it this time on the engine. They are all the original glow plugs. I guess I will just replace them all. Also does the relay or the wiring need to be replaced?

Thanks again for the help Phil.

David

 

The Relay and the wiring don't need to be replaced. They should be fine. But just to make sure that the high resistance that you measured in the two glow-plugs was caused by the glow-plugs themselves and not by their associated wires, measure their resistance directly (without the wires) when they are out of the car. If it still shows a high resistance than you know its the glow-plugs. If the resistance is now much lower, than it could have been a defective wire. Chance are however that its your glow-plugs and not the wires.

It would however be a good idea to replace the glow-plug strip fuse. This fuse has a tendency and a history of developing hairline cracks. It only costs a couple of Dollars. I suppose that you can keep the old one as a spare.


Phil