If you have a look on page two of the threads, I am having the same problem on my '03.

From what I have learned so far, you probably have glow plug problems. You should have resistance when the key is on.

Thats about all I know. Take a look at the responses to my post "Help me diagnose, lease"

 

You need to unplug the glow plug before you test it. You should show resistance across the glow plug, not 0 or infinity. Hope that helps.

 

When you say that I need to unplug the glow plug, do you mean that I need to remove it from the truck?? I tested it with the connector unpluged.

 

How good is your multimeter? Is it auto-ranging? Can you lock it in a range? The glow plugs should be a few ohms, so your meter needs to be set up to read a value that low. On the wrong range, a few ohms is indistinguishable from 0 ohms.

Duncan

 

I rechecked the resistance on my glow plugs today. When I first checked them the meter was set on the "2000" setting, and I got a resistance reading of 0.0. Today I set my meter on the setting of "200" and I got a resistance reading of 1.0 to 1.3 on my glow plugs (0.9 being the lowest and 1.3 the highest out of the eight glow plugs) The truck has not been started for about 3 days now, and our temps have been in the 20's of the night and mid 40's during the day. Does these reisstance readings mean the glowplugs are good?? are they bad?? I have checked about everthing that I know to check and it is still tough to start when cold. Also, I checked my battery voltage and they are both showing about 12.75 volts. Any help is greatly appreciated. Also, some back ground info (I called the guy I bought the truck from, I have had it about 20 months. He said a few months before I bought it he had glow plugs put in it due to it being hard to start in the mornings, he bought the autolights. I have read some bad things about them in this forum).

 

Can you set your meter to "20"? It sounds like the glow plugs are good though (pending anyone's experience with the Autolites.)

Here's a test you can try: when you first turn the truck key on, have your meter on the two BIG leads of the glow plug relay and measure the voltage. Should be 0 volts, because the posts are shorted together by the relay being energized. If you measure a few volts then the relay is crudded up and failing. If you measure 12V then it's not making contact at all.

Another thing to try - using one lead of a JUMPER CABLE (don't try this with some skinny wire) connect the two big leads of the relay for about a minute after you turn the key on... then try starting it. If it fires right up, there's pretty good proof your relay wasn't working but your glow plugs are.

Duncan

 

To me it sounds like your readings are good for both the glow plugs and relay. I would double check the high press. pump res. and check to see that the oil is no more than a 1/2 " below the top. Could be its leaking down over night? Also what is the weight of the oil you are using?

 

I checked the oil level in the high press. pump res., and it is near the top (within 1/2 inch) but I went ahead and toped it off to about 1/4 inch anyway since the I had removed the plug. I am running rotella 15w/40 conventional in the white jug. I bought some rotella synthetic in the blue jug the other day to switch to my next oil change due to the good things I have read about it hear on the forum.

 

I think there is something wrong with your GPR or GP's even though they seem to test okay. I agree with Frobozz, you should bypass the relay, although about ten seconds should be enough.

 

Ok, I'm gonna ask some stupid questions because I hate to see anybody start just trying parts, so bear with me:

You said you checked the battery voltage, but how old are they, and have you checked all the battery connections? These engines require a lot of their batteries, what with glow plugs, firing the injectors, and turning the engine. I have read a lot of cases here where mysterious starting problems were cured by new batteries.

You didn't say how many miles. If it is high mileage, have you ever checked for blowby? On of the first thing to go on any diesel that is getting tired is cold starting.

Have you checked the rest of the injector wiring harness? Your truck is about the right age to be having problems with it.

 

The fact you are getting white smoke while cranking indicates the injectors are firing. This rules out both low HPOP oil level and bad batteries. The engine is geting fuel, we can assume it is getting air since it runs eventually, leaving only heat (compression or glow plugs). This theory is further reinforced in that the truck starts fine after using the block heater. Try testing the voltage drop across the GPR. A good relay will show very little drop, whereas a bad one will have significant voltage loss due to the contact plates pitting and losing conductivity. You can also check for voltage at each glow plug to rule out bad under valve cover harnesses.

 

This is where I now stand. I tested the relay as sugested by Frobozz and it tesed to be good but I made a "jumper" and bypassed the relay anyway as suggested, still had the same problems with the engine not wanting to start. As for the question on the batteries, they were in the truck when I bought it, so I know that they are 2+ years old, and the month/year was not indicated/punched out on the batteries. I checked all the connections to the batteries and found no corrosion or visible damage. The batteries show 12.7 volts when the truck is off, and 11.8 volts with the key on and the wait to start light is lit up and gp relay is on showing it is sending power to the glow plugs. Is this voltage to weak?? The truck has 200K on it, but I have not noticied any oil loss when I change the oil, & I have not had to add oil to it between oil changes. How should I test for blowby?? While I was doing all this checking, a friend stopped by to lend his assitance and brought me his multimeter to use (incase mine is of poor quality or experiencing problems even though it was expensive) With his meter, the resistance I got on the glow plugs ranged from 0.4 to 0.8 ohms to ground. Thanks to all who have responded to me and thanks for all your help so far.

 

ok, did you test the batteries individually, while they are unhooked frim the cables? A common problem with these dual battery setups is that one battery sometimes goes bad, as reflected in another thread that just got started in this forum. Voltage will read ok, but they won't be able to produce the amps necessary to start the truck. I personally would take both batteries to an autoparts store and have them both load tested since you don't know how old they are.

 

i would like to ask something. are u useing diesel fuel treatment. that makes a heck of a difference with cold starts. i dont plug my diesel in. it was 22degrees the other night.
truck fired on second crank after sitting all night.
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also when was the last time the fuel filter was replaced?
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i personally would put the motorcraft glow plugs in it.
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