My 99 250, 7.3 is having some strange issues as of lately. When I start it in the morning, when the engine has fully cooled down, it starts right up, then it throws the "wait to start light" runs real rough and just shuts off. Run the glow plugs a few times, start it up and it will do the same thing for maximum 30 minutes, then all the sudden I start it and it runs fine. I have a few videos of it but idk if I can post on here? I can definitely send through text or email if anyone can help me figure this out that would be splendid! Every shop I've been to has no idea, I've replaced the fuel pump, cleaned the fuel bowl, new fuel filter, I just don't know where my problem could be. It doesn't make sense. But once I get it running and it warms up, runs fine all day. Go to bed, wake up, has problems again.

 

Maybe a high pressure oil problem. When was the last oil change? Do you have AE or torque to monitor the HPOP and other sensors?

 

Uh oh.... From the title, one may get the impression I'm "an authority" on these engines. I'm just a schlub that does OK at reading the sensors on these trucks and I've certainly run into a wider-than-normal variety of issues... but there are many fine folk here that can offer up things I overlook or haven't experienced.

I don't suppose you're running an OBDII app when this happens, are you?

When the WTS light fires off while running, that can sometimes mean a momentary interruption in power to the PCM - but the temperature observation brings a few new questions up. These questions are incredibly hard to answer without some OBDII sensor data.

 

Burr,


How is your oil level and when was the last time you changed it and with what.


These rigs don't like a drop in temps without a full pan and fresh oil.


Denny

 

Tully says he's a rookie but has helped many on here !

 

Last oil change was at 294,000 I'm at 297,500 now. Also I don't have either of those to monitor anything, I actually have no idea what they are.

 

Here's where it gets funny,, when I hook any obdii scanner up it will not start, at all. If I start the truck then plug it in, it kills the truck. I'm soooo confused. Also, oil level is good and it has 40w in it. Rotella T6

 

If anyone feels they want to watch a few 30 second to 1 minute videos of my truck doing its shenanigans just send me a text stating who you are and I can send it over real quick and hopefully someone has seen this problem before. My cell phone number is 513-340-8156

 

Straight 40W or 15w-40w?

 

It's got 15-40

 

What scanner are you using?

The interface is OBD-I, PWM-1850. The physical plug is OBD-II compliant, but not the protocols.

The wrong protocols/settings on a scanner could prevent a start. An example is pulling DTCs. If I clear the codes while the truck is running, it stalls EVERY time.

 

So was I, when my truck did the same thing while hooked up to Torque Pro. That is precisely why I asked the question. Mine worked fine until one day when I changed a PID. After that, everything was weird - including the WTS flashing off and on and the rough run when connected. I stripped Torque Pro out, did my OS updates, re-installed TP, did those updates, then programmed my PIDs again. It's been all good since.

Now... Car Gauge Pro was loaded and I did a buzz test. Things didn't work out so well there - it was like the truck was out of time after that. I fired up my AE to do a KOEO test, and it cleared whatever the hell was going on in there.

This is all assuming you have a proper OBDII adapter (I feel I have a high-quality one for $100). There is no telling how a Chinese "clear blue" knock-off will behave for you.

 

I would recommend taking your phone number out of the post above. Have people PM you and get in contact that way. There are too many weirdo's on the internet that will do God knows what with your cell number. The guys and gals that participate here are fantastic, but there are always lurkers who are not so good intentioned. Just my opinion. Sorry I don't have more to add to the actual discussion. Stick with Rich's suggestion at this point though.

 

Well here is what a blue Chinese Knock off MIGHT get...results and mileage may (will) vary....




I agree with going and spending a bit more for a high quality connector/scanner that will read these trucks...

 

This all sounds electrical to me.

Honestly the first thought that popped in my head is the ignition switch (the electrical part of it) may have a problem. It sounds as though the ignition isn't getting a good contact.

Now this issue could be anywhere down the ignition line, down to the PCM. It could be a bad connection at a module or the ignition itself or any of the connectors in between.

One other thing that is a possibility would be the battery connections, not so much at the battery themselves but at the relay/solenoids on the passenger fender as well as all the bare wire grounds from stuff like the passenger side head to the cowl, from the frame to the body under the passenger floor board, and the like.


Another thing that would cross my mind is a faulty module itself. Like the PCM or IDM or even something like the power saver relay in the cluster.

Electrical issues suck.

I guess I would start off by simply jiggling the ignition switch and then moving on to the wire harnesses and make sure all connections are clipped tight.