Got a strange new issue - when the truck has been sitting for more than 6-8 hrs, it becomes hard to start. Starts rigt up when warm. Runs ok normally, with no smoke or anything, knock on wood. If its only been an hour or two, I just glow for 10 sec and start right up. If its been longer than a couple of hours, I glow 3 to 5 times, 10 sec on 5 sec off. When its been longer than 6-8 hrs, no matter how I glow, its unpredictably hard to start.

It may fire right up, and die, and then it just turns and turns and turns, while pumping out white smoke. After 30-45 sec I either give up and wait for the starter to cool off, or it may fire up, and then if I throttle up just right, then it keeps going... For the first few seconds it feels like the idle is going up and down, as if I was still pumping the gas pedal...

I have fairly new 60G glow plugs that are manual via a 150A solenoid and 15A toggle switch; and fast idle + cold advance are wired through another 15A toggle switch. I think, it may be easier to start without fi/ca on - I start, throttle up, then flip the fi/ca switch on - but that may be just a perception...

So what is happenning? I've had a fuel filter sitting in my glovebox for the last year or so waiting to change it, this wouldnt be it, would it? what are the symptoms of a bad fuel filter on a 6.2? otherwise I am kinda worried about the injection pump, but why only when cold??? any ideas???

I've also heard something regarding never giving diesel throttle when starting or braking or something, I ve never followed that rule, any truth to it and why?

might be more inj. issue. make sure your lift pump is working . leave gas cap loose after parking to see if that helps. i never had the 60g glow plugs to know how long is to long. maybe old diesel add alittle diesel fuel conditioner. tee a pressure gauge between lift pump and ip to see if it has to do with holding fuel pressure.

sounds like air getting in fuel lines when it sits. had same problem till i changed factory filter setup to a screw on style

Somehow, you are glowing too much. Unless it's close to freezing, it shouldn't take more than 10 seconds of glowing with 60Gs to get the engine started almost immediately on the first try.

It sounds like you have an air leak, but it could also be bad batteries, bad battery connections, a weak starter turning too slow or the IP going bad. I'd check for an air leak first and eventually change the fuel filter.

First... As lee noted, don't bother with cycling the glows that much. Just hold them for ~10 seconds and start it.

Second, change your fuel filter. You're going to do it eventually, I would get it out of the way now as it sounds like it has been a while.

Third, sounds like you have an air leak or perhaps a lift pump that isn't the best. I would test for fuel system leaks (see the section in the FAQs for information on testing for leaks).

might be more inj. issue. make sure your lift pump is working . leave gas cap loose after parking to see if that helps. i never had the 60g glow plugs to know how long is to long. maybe old diesel add alittle diesel fuel conditioner. tee a pressure gauge between lift pump and ip to see if it has to do with holding fuel pressure.

how can I test the lift pump? <-does leaving gas cap off test that? or fitting the fuel gauge? <- I will try that, good idea... will I need to bleed off the system after I install the T connector? <- I dont have a compressor available :(

the diesel gets circulated through pretty fast, in fact much faster than I prefer... and at $3.99 per gallon it all adds up...

sounds like air getting in fuel lines when it sits. had same problem till i changed factory filter setup to a screw on style

I think I should change my filter this weekend, man, I hate giving up... and I will check for air leaks once I figure out my lack-of-compressor issue...

Somehow, you are glowing too much. Unless it's close to freezing, it shouldn't take more than 10 seconds of glowing with 60Gs to get the engine started almost immediately on the first try.

It sounds like you have an air leak, but it could also be bad batteries, bad battery connections, a weak starter turning too slow or the IP going bad. I'd check for an air leak first and eventually change the fuel filter.

interesting, I did not think I could "glow too much" - can anyone elaborate? I figured the more I warm up the engine, the better? I'll try only glowing once for 10-15 sec and see whats up...

could be bad connectors, but why only when cold??? bad batteries could very well be, because I had a short recently that was draining batteries, which are way old and mismatched, but tested good at autozone last week... btw, how many CCA's do these need with a stock starter? I remember reading something about changing to a 6.5 gear reduction starters, would that make a difference? and still, why only when cold? maybe cuz the oil is thinker and harder to spin? I gotta change that too sometime soon its way old...

...Third, sounds like you have an air leak or perhaps a lift pump that isn't the best. I would test for fuel system leaks (see the section in the FAQs for information on testing for leaks).

any way that can be done without an air compressor?

also, does "lift pump" refer to some sort of a mechanical fuel pump? where is it located? how can it be tested and can it be replaced with electric?

btw, this morning I plugged the block warmer for almost 2 hrs and it started fine, but after sitting 10 hrs at work it gave me some temper... it does turn kinda slowish... so I wouldnt eliminate the baterries or the starter just yet,maybe I have a slow drain that gets them low? will check the voltage overnight... hmmm... sounds like I have a few things to play with, any more ideas are welcomed

how can I test the lift pump?


You can test them with a pressure gauge in the fuel line going to the IP. You should get between 5 and 9 PSI fuel pressure to the IP.


interesting, I did not think I could "glow too much" - can anyone elaborate? I figured the more I warm up the engine, the better? I'll try only glowing once for 10-15 sec and see whats up...


What I meant to say was that you are glowing too much ... meaning that you should be able to start the engine after powering the glow plugs for about 10 seconds. If it's cold (like freezing), it can help a little to glow for 10 seconds, wait for 6 seconds and then glow for another 6 seconds or so. It can also help to keep the plugs powered while cranking.

If you have to glow 3--5 times and/or it is still hard to start the engine, then there seems to be something wrong. Since your glow plugs are fairly new, it's probably something else than glow plugs.


bad batteries could very well be, because I had a short recently that was draining batteries, which are way old and mismatched, but tested good at autozone last week...


They can be bad even when tested and found to be good. I have had a set that tested ok and was still useable for starting, but they would drain itself within a week or two if not charged (by driving).

Things can be worse when the batteries get cold. The chemical reaction inside the batteries slows down in the cold.

Also, as you suspect, the oil is thicker when cold and makes it harder to turn the crankshaft.


btw, how many CCA's do these need with a stock starter?


A while ago someone posted here that the starter can draw 750amps when cranking and twice that when blocked.

Since the batteries are wired in parallel, they should be the same as much as possible: same voltage (of course:), same capacity, same manufacturer, same model.

The starter needs to get to about 300 RPM to start the engine. If it's turning too slow, it won't start.


also, does "lift pump" refer to some sort of a mechanical fuel pump? where is it located? how can it be tested and can it be replaced with electric?


Yes, the lift pump is a fuel pump which is supposed to pump fuel from the tank through the filters to the injection pump. It is bolted to the block on the passenger side. You can test it with a pressure gauge as described above, and you can replace it with an electrical pump. But it's important that the electrical pump supplies the correct fuel pressure and provides sufficient fuel flow.


will check the voltage overnight... hmmm... sounds like I have

That's a good idea. Let us know what you find ...

^^^ wow, that prety much covered it all, thanx a lot man!!!
I will be dinking around with it this weekend, we'll see what happens

another q: when it turns and turns and tries to start, it pumps white smoke - does that indicate anything? no smoke when running...

also, sometimes when I drive around, it feels like it throttles up by itself, like if someone was freeing up some sort of restriction or adding air/fuel, fells like it gains power...

oh yeah, leaving the gas cap off for 10 hrs during the day today did not help with the start - had to crank it for good 30 sec... and also, i am still wondering if putting a T in the line will introduce air to it ? oh, and is there a way to bleed the lines without an aircompressor? I guess that was more than one question... thanx in advance, everyone!

Far as I know you dont need a air compessor to bleed the fuel system.

My truck is the same way. But Only first start of the day. If i go out 14 hours later and start it it's hard. but anything before 14 hours she fires right up. When I do have trouble starting it she "smokes" the street out. As in thick WHITE smoke that is thick enough to make it look like fog...

If you're getting white smoke when cranking you should be looking at your glow plug system. White smoke is unburnt fuel, indicating that it's probably getting fuel... Combine that with the fact that it only causes problems when it cools down all the way and I bet you're looking at a glow plug issue.

Check the plugs themselves and check to make sure they are getting power. These tests can be done with nothing more than a test light.

To check the plugs, disconnect the wire to the plug you want to test, connect your test light to the + battery terminal, and touch the probe to the spade terminal on the top of the plug. The test light should light up, if it doesn't the plug is no good. Test all the plugs, if one or two are bad it shouldn't cause any real problems, but it may run a little rough when you start it.

To test for power, connect your test light to a ground, probe the wire to the glow plug and then turn the key on. The light should light for ~8-10 seconds and go out.

also, sometimes when I drive around, it feels like it throttles up by itself, like if someone was freeing up some sort of restriction or adding air/fuel, fells like it gains power...


Take a look into the valley on the engine where the IP sits in: Does it look wet, like from fuel leaking out somewhere?


and also, i am still wondering if putting a T in the line will introduce air to it ? oh, and is there a way to bleed the lines without an aircompressor?

A T for a pressure gauge? Yes, that will introduce air, and you should bleed it out very much like when changing a fuel filter[1]. If you put a gauge in front of the IP, it can take some cranking to start the engine since some air will be left in the line going to the IP.


[1]: see http://www.dieselplace.com/forum/showthread.php?t=128587