OK, I just installed a new PMD and relocated it behind the front bumper. I Thought the hard start was from the PMD but It is still doing it. It has gotten worse and worse in the past month. Now it is taking 10 sec of cranking before starting. This is both hot and cold. Ill test the glow plugs but I dont get much of any white smoke on start up. Ideas? thanks, matt
passes the lift pump test by the way.

Check the fuel filter. How old are the batteries and condition of the cables? The engine has to spin fast enough for the fuel solenoid to build pressure to open the injectors. The GP's are really important when cold. An old trick which works also is to unplug the coolant temperature switch. This puts this circuit into default to -54* coolant temp. The GP's will burn longer. Do you have any stored codes for the IP ?

OK, I just installed a new PMD and relocated it behind the front bumper. I Thought the hard start was from the PMD but It is still doing it. It has gotten worse and worse in the past month. Now it is taking 10 sec of cranking before starting. This is both hot and cold. Ill test the glow plugs but I dont get much of any white smoke on start up. Ideas? thanks, matt
passes the lift pump test by the way.

how old are the injectors?, the pintles are very soft on the original gm injectors, and they tend to wear out in about 50k or so, ive even seen them dead after 20k.
step 1, check to make sure its cranking well (good battery, good starter)
step 2, check the glows
step 3, got fuel? lift pump, filter...
step 4, check the injectors (pop test, 100% replacement if more than 2 fail)
step 5, compression test (i usually do this when testing injectors)
step 6, injection pump, replace/test these pumps do actualy fail mechanicly, although usually the electronics die far before the mechanics do


vin

I cant check the glow plugs and other things until Fri evening but I can tell you...
The engine cranks well. When the no start problems began I cleaned the bat terminals and it improved charging and cranking speed. I did a vin check when I bought the truck (1GCHK34FOSE179434) and no sign of glow plug or injector replacement. Will injectors cause no/hard start?
The lift pump seems to be working but Ill check it again this weekend. Ill have more after Fri. Thanks, Matt
PS. Does anyone have a link to the pop test for the injectors?

I cant check the glow plugs and other things until Fri evening but I can tell you...
The engine cranks well. When the no start problems began I cleaned the bat terminals and it improved charging and cranking speed. I did a vin check when I bought the truck (1GCHK34FOSE179434) and no sign of glow plug or injector replacement. Will injectors cause no/hard start?
The lift pump seems to be working but Ill check it again this weekend. Ill have more after Fri. Thanks, Matt
PS. Does anyone have a link to the pop test for the injectors?


Injectors can cause all kinds of hard start problems..
check you yellow pages for a diesel engine shop, most shops sould be able to do this for you...

vin

I just got off the phone with my brother who was nice enough to check some things out for me 2hrs away at my truck.
The glow plugs are reading 1.4-1.7 Ohms except one that is reading ~200KOhms. Is this F'ed up? The bateries were replaced in '04. I would think they are still good. In the mean time Im trying to get ahold of a local diesel mechanic. Any help still appreciated. matt

I just got off the phone with my brother who was nice enough to check some things out for me 2hrs away at my truck.
The glow plugs are reading 1.4-1.7 Ohms except one that is reading ~200KOhms. Is this F'ed up? The bateries were replaced in '04. I would think they are still good. In the mean time Im trying to get ahold of a local diesel mechanic. Any help still appreciated. matt
it should be between 1.5 and 2 ohms.. 200k.. defenatly hooped..
however.. i doubt that 1 bad glow is causing hard start.. best way is to drop the exaust, and pull them all and test on the bench. hook them up to a 12v battery for 10 sec and they should be all nice and cherry red at the tip.
Dont do this for more than 15 sec, because they will melt down if you leave them on too long. also watch you fingers and skin.. needless to say.. burning flesh is a BAD smell..

if you have an ammeter even better, the draw should be between 8-10A depending on how well charged the battery is.

if more than 4 fail, replace them all.. dont bother with the gimmick stuff like fast heat etc.. it wont make much of a difference unless you are running lowered compression etc (IMHO).

another check you could do, is to make sure you have voltage present at the glow plugs when the glow light is on. but this takes two people to do, unless you have a scan tool

also while the glow plugs are out you might want to do a compression test.. just make sure you do it with all the glow plugs out to get the best results.

next if its still hard starting once you get the glows back in, (dont bother with the downpipe until you have the problem licked) and the compression is good. then you have a choice.. injection pump, or injectors (my beer money goes on injectors)..

pull them, pop them and rebuild any failed ones.. if more than 2 or so fail, rebuild them all, no sence taking any chances...

just make sure that when you put them back in, that you dont remove the caps until you are about to connect the fuel line.. its amazing how tiny a spec of dirt can cause all kinds of new problems (cost me $1200 to find that one out)

all this (less the rebuilding of injectors) should be able to be done in a weekend worth of time..

good luck..

vin

Matt I just changed my glowplugs and injectors this past weekend. It wasn't to bad of a job, took 2.5hrs to do the drivers side and 3.5-4hrs to do the pass side. I have the injector socket if you should need to use it. just pm me or give me a call.