Cold start problems

[Enslow]

Hey guys, having some issues with my excursion. Last year it started. When it gets to 50 degrees or colder the truck has a really hard time starting. After plugging it in it will start. I’ve switched to 5w oil, new glow plugs, glow plug relay, valve cover harness and new hpop. The batteries have been checked and are good. 750 cold cranking amps.

This past weekend of course the temps dropped and truck wouldn’t start. At this point I’ve debated on taking to a shop. But would rather not. Could the starter just be weak in the cold weather? Any help would be awesome.


Sent from my iPhone using Tapatalk

 

[dmd]

Are you sure the glow plugs are really turning on? Did you check the relay is
really activating?

 

[justinlogue5_0]

I may have missed it but could you explain better the "will not start" issue it self? As in, Does it turn over fast but doesn't crank, or turns over sluggish like weak battery's would, or doesn't turn over at all?

 

[DEEZUZ]

Alot of white smoke?

Injectors cackling?

 

[Enslow]

If it does start there is some white smoke initially. The crank will start off strong then die down. The batteries aren’t but 6 months old. I’m thinking the starter could be going or weak. Harder to start when it’s cold. As far as the relay I haven’t a clue how to test the excursion style relay. It’s an inclosed box. It is brand new though.


Sent from my iPhone using Tapatalk

 

[DEEZUZ]

Glow plug control module. You'd have codes if there was an issue there.

You need cranking speed. Fix the battery issues, get a high torque starter, clean grounds at block and frame

 

[dmd]

I have that module in my 2000 CA 7.3. Have a voltage meter plugged into the lighter socket
or something, note the voltage with everything turned off. Turn the key on and if the
voltage drops about two volts you know that plugs are turned on. Now .. if all if them
are working is another thing.

Mine throws a code, but it is from the missing intake heater

 

[Arisley]

Before spending a bunch of money, you need to do a simple thing. Compression test.

 

[Enslow]

It doesn’t have any blow by. Only smokes on initial cold start then nothing after.


Sent from my iPhone using Tapatalk

 

[Enslow]

Update. Low crank turned out to be bad starter. When I swapped with high output I found half the positive post was broke. Which completely broke off when removed it. Borrowing a scanner to check both opt and Icp to be sure. I have a feeling the injectors might be the issue.


Sent from my iPhone using Tapatalk

 

[Enslow]

As you can see positive post broke off at starter


Sent from my iPhone using Tapatalk

 

[Enslow]

Wondering if anyone has come across this before. Ended up taking the excursion to a local shop. Looks like once the pcm is grounded the glow plug module sends power to glow plugs to light. Otherwise the module isnt sending power to the plugs. Has anyone come across this? Could it be a bad pcm, possibly the chip? Which is just a ts with basic tunes.


Sent from my iPhone using Tapatalk

 

[Enslow]

Bump.
Still having issues starting in the cold. My windshield was leaking which I had replaced. Thought this might have something to do with it. I sent out the pcm to a place in Florida to have checked over. They said everything was fine with it. I then checked all circuits from pcm to Glow plug module thinking there might be a broken wire, was getting 8.6ohms from connector to connect and checked all grounds as well 8.6 ohms to ground from pcm connector to negative on battery. Trying to figure which direction to go next to resolve.

 

[6.0 Tech]

Bump.
Still having issues starting in the cold. My windshield was leaking which I had replaced. Thought this might have something to do with it. I sent out the pcm to a place in Florida to have checked over. They said everything was fine with it. I then checked all circuits from pcm to Glow plug module thinking there might be a broken wire, was getting 8.6ohms from connector to connect and checked all grounds as well 8.6 ohms to ground from pcm connector to negative on battery. Trying to figure which direction to go next to resolve.

8.6 ohms is way too much for your wires. Should be under .5 typically.

Sent from my VS988 using Tapatalk

 

[Enslow]

So what could the issue be if I’m getting those readings on end to end, both from connector to connector and through wires, as well as to ground.


Sent from my iPhone using Tapatalk

 

[6.0 Tech]

Could have a corroded connector inline somewhere, pinched wires, rodent damage, corroded wires, the list goes on. Look for inline connectors, like the one on the drivers valve cover, and go from there, both directions, to isolate which side your issue is on.

Sent from my VS988 using Tapatalk

 

[Enslow]

Thanks I might just remove the engine bay harness to make life easier for testing


Sent from my iPhone using Tapatalk

 

[DEEZUZ]

This is where using a headlight works wonders I nstead of ohming out wires. Putting an actual load on each wire will tell you if the wire is at fault. Disconnect the harness at the VC, put one end to the hot side of an old sealed glass headlight, ground the light, then feed 12v at the opposite end of the wir harness. If light lights up bright, wires good and can carry a load. If dim, wire is bad.

 

[6.0 Tech]

Whs^ A wire will show good continuity with only 1 strand connected, due to the low voltage/amperage coming from your meter. But with it showing hi resistance, it should be fairly easy to find...

Sent from my VS988 using Tapatalk

 

[Enslow]

Update:
Of course winter has rolled around again. This go round we have a baby on the way so I haven’t had time to work on the excursion. Ended up taking it to the dealership to do some recalls as welll. Turns out it was my chipped key that had failed not causing it to start when it’s cold out.


Sent from my iPhone using Tapatalk