Here goes.....
I'm in california and as the weather got colder my truck became harder and harder to start.
What I would do is turn the key to "on" untill the "wait" light turned off and then do it again 4 times and then crank it over and it would start.
Then the other day it just would not start at all.
So I gave it a shot of either(I know ,I'm Bad) and it started and ran great all day.
Next day since it has 183,000 miles on it I got 8 motorcraft glow plugs and 2 valve cover gaskets.
I installed all of it and figured my problems were solved.
I cranked and cranked to no avail!!!!!
Maybe another shot of either(I know I'm really bad!!) but desperate!!!
It did start but sounded like it was running on 3 cylinders and when I gave it the gas it did'nt want to rev up although it did but slowly.Also the service engine soon light came on.
So turned it off, cryed a bit then checked the 9 pin plug at the valve covers.All the glow plugs measured 1.7 ohm's and the injectors measured 0.??? I thought there would be some reading. I went from the center (common) to the 3,4,6,7 pins. My truck came from washington state so it has a glow plug relay,(which I have not checked yet) but it seems now that the glow plugs are not the problem. Oil level is fine even though I'm not sure how long since I changed it(guessing 5000 miles)
Any clues on this adventure much appreciated!!!!!!!!
Rick

 

Since you had the valve covers off, it would've been a good idea to just go ahead and do an injector o-ring change and what the heck, replace glow plugs (cheap & easy like spark plugs). There's a process though, so research proper steps like purgiung oil etc. I chased down a hard start cold/no start warm problem recently and have a couple posts on it (search posts by Reckless).

But you could do a search here on removing & cleaning the IPR. Also check your IPC connector for oil in the connector. Quick test is to unplug it and see if any oil is present in the connector itself (if so it's bad). And/or unplug it and see if you notice any difference in starts. Free and easy start to pocess of elimination. If not already do a cheap change of the CPS as well. If so, change it. Oh yeah, check oil level in the HPOP reservoir. Again a search of hard start cold/warm will reveal a ton of info/steps to take to check off the basics on a set of issues that has some common denominators in the troubleshooting process.

 

I see you already did the glowplug thing with Motorcraft parts... good job. The VC gasket was a good call, but the wiring harness was not mentioned. It sounds like a bad wiring harness, or you may have accidentally undone one connector when working on it. The best/easiest place to test the connections to the injectors is throught the 42-pin connector. Other than that, click those last links in my signature for troubleshooting tips.

 

Did you check the condition of your batteries? Fully charge the batteries.
Do not cycle the key on and off several times. The glow plugs stay on for up to two minutes when you turn your key on based on oil temperature. The wait to start light is just a timer. It does not tell you that the glow plugs are energizing.
Fully charge the batteries. Turn the passenger side mirror down so you can moinitor the smoke coming out of the tail pipe while cranking. If you have a way of monitoring voltage when the glow plugs turn on and while cranking then this will help.
Turn your key to the on position and wait a full 60 seconds for your glow plugs to heat up and transfer some of that heat to the cylinders.
Now turn the key to the start position to turn over the engine. Let it turn over for at least 15-25 seconds. No longer than 30 seconds at a time.
What color smoke if any is coming out of the exhaust?
If you are getting white smoke then the injectors are firing and the fuel is not being burnt.
If you are not getting any smoke then you need to be looking at what your battery voltage is while cranking (and the glow plugs still energized). Is the voltage above 10.5 volts? If not above the 10.5 volt output then the PCM will not tell the IDM to fire the injectors.
In this case you need to fully charge the batteries independent of each other and have the batteies load tested at the auto parts store. If both batteries are load tested in good condition then you should look at your starter to see if it is turning over normal or if it seems labored and tired. That starter could be pulling your voltage down due to being weak. These are all things I would be looking at.
Do you have a way to pull codes? You have the GPCM and it might be going bad. Auto Enginuity could tell you what codes but that is another 360$ if you don't have it already.
Do the basic test and measure voltage if you can while doing those cranking test. This will tell us a lot and we can help you further.
If one battery is bad then replace both of them. Do NOT replace just one battery.
My trouble shooting technique will not cost you anything except time.
NO MORE ETHER. BAD.

 

To check the pins on your harness. The pinout is as follows:
G-G-I-I-C-I-I-G-G
G= glow plug
I= injector
C= injector common
meter on ohms/resistance on the lowest setting....Place red lead on injector common and the other lead on each I pin to check the 4 injectors on that side. You can check it from the 42 pin connector as Rich has shown above. That check the entire cable from the 42 pin connector to the injectors. I am sure your glow plugs are good. not so sure about your GPCM or any codes that are in your PCM that can help us here.

 

Check your oil level.

 

Thanks for all the input!!!! Can't get back to it untill tomorrow.What I did not metion was when I cranked it the starter would slow down after 10 seconds so I would stop and wait for the "wait" light to cycle off and crank again,also pumping acelerator pedal and getting lots of white smoke.batteries are die hard and not very old
(8 months?) Wireing under valve covers looked fine. How to test injectors useing the 42 pin connector??? Thanks again and I will let you know what happens,Rick

 

Where are you in California?

 

If your starter is slowing down, I bet you have a bad started or relay if your batteries all checked out. You can use a test light on the relay for the glow plugs to check them. One side to ground always has power, the other side only with the key on. These are the big posts. If you don't get power to the other side, the relay is bad, even if it clicks! This is on a cold engine and oil as well.

 

D+ is driver-side common. Even numbers are on the driver side. Without inserting the multimeter probes into the connector (just touch the metal edges), check from common to the injector number on that side. It should read around 3 to 4 ohms, if my memory is holding up. If you have a reading over 5 or open... bad connector somewhere. Start your test by shorting your meter leads to gether to make sure you have a good reading there.

 

I'm in Redwood city CA,which is exactly between san fransisco and
san jose

 

As I was running out today I just could'nt resist checking the glow plug relay,only take a minute right? so I connected the meter to batt ground and to thepost that had no rubber cover on it ,turned the key to on and.............nothing. so then I just poked under the rubber cover with the probe and ..........nothing also!! What?!?!,had to go so I'll be looking at that a biy closer tomorro....weather permitting

 

Thanks I get it P for passenger and D for driver.That seems like it will be easier than checking at the VC

 

Just thinking out loud here,The truck was running fine before I changed the glow plugs(even though it was having a hard time starting) it seems I must have maybe disconected some injectors in the process??? I'm going to check that first thing.someone mentioned that I should have done the injector O-rings while I was in there(did'nt know about that). Any body got the scoop on that? Also re torquing injectors and pedistools?? maybe I need to get back under those covers anyway,wernt so bad ,only about 4 hours work.

 

Backup for a minute, if neither large post on the GPR ever has power something is wrong. recheck that and I would recommend taking the time to remove the battery cables and cleaning them for the starter rpm issue first. Even if you see not corrosion, the oxidation that is there is enough to make the starter spin slower than it should as you are not getting full power.

If you recheck the gpr and still have no power, check both large terminals on the AIH relay and see if either of them has power. The battery feed for those is the same iirc.

Another question i have is are you still getting a wts light?