My truck is starting hard. Usually takes multiple tries. It almost catches and fires up but won't until the third or fourth try.

It's not throwing any codes, so I assume that all of the glow plugs are working. The glow plug relay is a month old so it can't be bad, I hope. It's belching black/gray smoke so I assume its getting fuel. I already changed the fuel filter so it is new.

Could I possibly have some rotten fuel. I also added a healthy amount of anti-gel (maybe the stations switched to non-blended, it has been chilly) So I am trying to see if plugging it in helps. Could the other fuel filter be bad, the one underneath the truck?

I'm stumped.

 

Try jumping the relay for the glow plugs just to make sure that's not the problem.

How many miles does it have?

Bad fuel will make it run rough, but the fact it's putting out smoke tells me the injectors are firing. Glow plugs would be my first guess. Under Valve Cover Harness is another possibility.

How cold is it?

Are you running bio-diesel? Bio-diesel has a higher cloud point than regular diesel. Even if it's cloudy, it should at least fire up. If the fuel has gelled, that will keep it from starting.

 

I'd guess its the glow plugs or under valve cover wire harness too! When its below 30 degrees F my truck [99' 7.3L] likes 10w-30 oil instead of 15w-40.Plugging it in should solve the problem it always worked on mine.

 

When it starts, it runs fine. The temps are ranging from the 20-40s. Not running bio-diesel.

When the valve cover harness failed the truck lurched, died and wouldn't start. Wouldn't the glow plugs throw a code?

If they are bad how do I know which ones aren't working right? I'm getting sick of throwing money at this g*ddamn truck every other month. It's just annoying little stuff but it adds up quick. I have 140k in miles

Jumping the relay??

 

If the glow plugs are bad, you replace all of them at the same time. As for jumping the relay, do what I said above first. If the light does not dim like I said, then you have either a glow plug relay not working, or the glow plugs are bad. If the light does not dim, find the glow plug relay. Take a screwdriver (an old one that you don't care if it gets burn marks on it) and cross the main terminals with it. What you are doing is completing the circuit and bypassing the glow plug relay. Keep the terminals crossed with the screwdriver for about 30 seconds or so, (the screwdriver will get very hot) then go start your truck. If it fires right up, you've found your problem. When you change the glow plug relay, you need to make sure it has good contact where it bolts up to the bracket.

 

Well. the light dimmed. so glow plugs ok. so...?

 

I'm going to ask for a mod to put this thread in the 99-03 7.3 forum. There are guys there with a lot more knowledge than me.

 

How does it crank? I had a simular issue and it ended up being the batteries. They both tested fine at AutoZone but I have been told that even though they test good it doesnt mean they have enough amps to turn over most diesels.

 

I forgot about that. However it's not the amps, it's the volts. When voltage drops below 11.6 I think, the IDM won't send any signal to the injectors. But he is getting smoke out the tailpipe so it must be doing something.

BTW, I sent a notice to a moderator about moving this thread to the 99-03PSD Forum. There are guys there that know a lot more about these engines than many mechanics. It will get a lot more attention.

 

PJ, don't get disgruntled with your truck. The folks in the 7.3 forums know a lot about these trucks, and they can talk you through most any repair.

 

I stand corrected. I knew it was something along those lines. Also if it is the batteries dont cheap out on them. Get the absolute best you can afford. These 7.3s eat batteries and alternators alive.

 

With low voltage, they will still crank like nothings wrong except they don't fire. But if smoke is coming out the tailpipe as PJ's truck is, it might not be the batteries. Of course putting a battery changer on them ain't hard to do to see if that does the trick.

 

I thought I was in the 7.3l forum. Crap. I love having kids that distract me.

Anyways, batteries are less than a year old and I didn't skimp. I bought Interstates. I wanted the Optimas but I couldn't afford them so I got the next best thing.

I have it plugged in now and it fires right up. I went and got some of that BG244 stuff, maybe it's just filthy injectors.

But it's still confusing the hell outta me.

 

Dirty injectors will make them hard to start. I think you have an issue with the glow plugs though. If plugging it in lets it start up, leaves me to think you have a glow plug issue.

 

But the lights dimmed like you had mentioned. I'm gonna use the injector cleaner and add fresh fuel, then drive the heck out of it.