I've got a 2003 6.0 diesel. We live in Colorado. High yesterday was about 15. Went down to -8 last night. High today was -1. Tonight is -8 right now, on its way to maybe -18 to -25 later.

The car has been pretty good so far in the cold. This is our second winter with it.

It cranks pretty slow in extreme cold but starts right up.

This morning it was tough to start. It cranked slow, started and died, then started and ran rough for a while and smoothed out.

My wife was driving the car around today and said it was running rough, kind of lumpy.

I took it out around 7 tonight (-5 outside). Drove it about 1/8 mile and it lost all power (not electrical power but just power). More throttle did nothing and it just stalled in the middle of the road. It started again after a few tried and I hobbled home.

I decided to mortgage the house and buy two new batteries. Put those in and the car cranked nice and started up. Drove it down the road and back and on the way back (same 1/8 mile as before) and it started dying again. I didn't give it any extra throttle and let it sort chug along really slowly. After a few seconds it cleared up and started running ok again.

I'm not familiar with cold weather and diesels. I started reading about diesel additives for cold weather. I added some tonight that I bought when I picked up the new batteries.

I'm wondering if this stalling rough running issue is the diesel gelling up?

The car seems to stall out when I try to go past say half throttle. Did I clog up the fuel filters with gelled up fuel?

Do you guys add additive during cold weather?

Should I consider an engine block heater? Oreillys has an OEM type heater that has a heater probe that goes into a threaded freeze plug location. Any experience with these?

Thanks for any advice or help.

 

I have always run additive in my diesels for multiple reasons. This year is an unusually cold year. I had four of my diesel buddies who I have told each to run additive have fuel gelling problems. They all do additives now and no problems such as you were describing since. I would get some additive in and the drive it for awhile to get it past the fuel bowl and through the injectors. My good buddy said when he pulled his fuel filter to put diesel 911 in it the fuel on the filter looked like jelly. Good luck 9905

 

We run Howes diesel treat during the winter in our diesels, works great, no fuel gelling down to past -20F.

I would definitely install a block heater if your truck doesn't have one. I don't even like to start my diesel under 20f if it's not plugged in. Just sounds like the poor thing is clanking for dear life when it's that cold. If it's been plugged in over night it fires right up plus you don't have to wait forever for the heater to warm up the cab.

One of the few things I do love about gas engines is how fast they warm up and how toasty they get along with not having to worry about plugging them in at night.

 

Your excursion should have the block heater installed already from the factory. Look next to the starter on the block for a plug in port. You would just have to buy the cord to plug it in.

 

Wow, great advice from everyone! I will look for the factory heater. Just a cord would be awesome. If its not there, I'll definitely buy a full heater today.

Yeah I hear about the poor diesels starting in the extreme cold. Ours clanks and chugs away for a few minutes as it gets warmed up. Meanwhile, our 96 Blazer with 202,000 miles on it starts right up quietly and is happy. I am running synthetic Rotella 5/40 and Rev-X. Can't do much more on the oil side of things.

I was considering taking the cap off the fuel filter under the hood and pouring a very small amount of the additive in there. Any thoughts on that? I think we may have gelled diesel somewhere in the fuel system.

We're going to be under 20 degrees for a few days. Last night it got down to -12. Its -5 outside right now at 9:30, going up to 15. I want to try and get some of the additive all through the system. I don't think it'll make it go the gas station right now to add more fuel and additive. I was going to buy a 5 gallon gas can, put some additive in it and fill it with diesel and bring that home. That way I'd have a good mixture in the tank.

 

Do you have a tuner on this vehicle?

 

Fuel additive and block heater for sure when it's getting into the negatives. Any way of checking you FICM board voltage. Cold weather and low voltage can kill a FICM making it hard to start and hard running if the voltage on the board is under 48v's.

 

mecdec: I do not have a tuner. (the FICM has a tune though) What were you thinking?

weekendwarrior: I do have an Auto Engenuity setup. I can test FICM voltage with that. The FICM is about 6 months old and under warranty...

 

Locally a buddy called me this morning with a similar problem and I instructed him to go back to stock tune.

 

Well problem fixed. Thanks everyone for your help. Car is running good now.

I think the issue was two-fold.

1. diesel additive - I think the fuel had started to gel up after numerous days below 15, some well below 0. Day time today is 4. I put some additive in the tank, I took off the fuel filter cap under the hood and put a tiny amount in there, and once the car was running reliably, I went to the gas station and put more additive in the tank, then added 10 gallons of diesel.

2. the engine block heater. I found out that I actually have one! Thanks nmlewis! Reps sent. Its by the starter and the wires run up to the front by the passenger side tow hook. I plugged a heavy duty extension cord into. Tomorrow morning will be the big test to see if it works and helps with the cold.

So with diesel additive and the block heater and two new batteries, things should be good tomorrow morning.

The car has always started right up in the cold mornings, with a pretty slow crank mind you, but its always started and successfully warmed up. With the extreme cold we've had, I think the diesel started gelling up and the car just couldn't run right. Can't wait to see if the heater makes a difference.

 

Great news. Normal advice is always use an additive to add some lubricity that the injectors need.

In winter dieselkleen white bottle, gray bottle in summer.

Available at local parts store or walmart.

Get an odb2 port gauge, scangauge2 or apps for smartphone & adapter.
Need to ensure ficm voltages are good as well other things. Very useful devices and tons of sensors to read to help diagnose issues while they are small..

Sent from my Sprint PC36100 using IB AutoGroup

 

Thanks misky6.0. I will checkout the additive when I run out of the one I just bought.

I have an auto enginuity setup. I'll be monitoring the systems tomorrow.

 

Glad you found the block heater, bro.

Try a Grill cove also: http://www.cabelas.com/checkout/item...95&WTz_l=Chart