I replaced two glow plugs on the passenger side this fall. As the temps were dropping, the truck didn't smoke nearly as much as it used to on startup. Almost no smoke at start. When the temp was still above freezing (30s-40s), the smoke would disapear by about 2-3 blocks of driving. Now that the temps have dropped into the single digits and teens, it smokes about halfway to work (about 15 miles). Is it possible that the GPR was marginal and is now not able to handle all 8 GPs?

Now that the temps are starting to approach 0, the truck is getting harder to keep running after sitting for the day or overnightt. I usually wait 15-30 seconds after the WTS light goes off before I attempt to start it. After about 5-10 seconds, it fires off and starts without issue. Depending on the day, it might stay running or it might not. Somewhere between 10 and 30 seconds after the engine starts, the engine dies. I can restart it. I may have to repeat the process 2 or 3 times before I can give it enough on the pedal to keep it running (I don't hit the pedal unless it's running). It doesn't seem to matter whether I plug it in or not, though it's better behaved if it's plugged into a timer in the garage.

I was running Kwik Trip winterized Diesel. As of tonight, I switched to BP Premium which is 30% #1 with PowerService added by the station. The temps dropped pretty rapidly. About 3-4 weeks ago, we were still in the 40s - 50s. Now, tomorrow's HIGH is supposed to be 3.

I replaced both batteries and starter last year. One of the batteries was toast. I had alot of trouble just getting it to crank in the cold weather last year.

I have 5W-40 Rotella Synthetic for oil Probably about 5K or less on this change.

After some reading here, I'm thinking GPR, Fuel Filter, clean FPR screen for a start.

Any other ideas of what to look for?

96 F250 Crew Cab 7.3L

 

TEST the GPR, esp. voltage drop. If it's more than spec (0.3V, IIRC), consider an upgrade such as the Stancor. Are you plugging the block heater in?

 

Yep.. block heater is plugged in at night. I tested the GPR voltage before I put the new GPs in. Voltage was good then, which is why I was asking if the GPR could be borderline and then go bad. It seems to work, but doesn't seem to stay on as long as I remember it staying on before I changed the GPs (based on the voltmeter in the truck)

 

try jumping the two big post on GPR it with a screwdriver for 15 to 20 sec. and see what happens. watch it the screwdriver will get hot

 

if it is firing up in 0 degree weather then i am sure teh relay is working. 0 degrees is pretty dam cold, how many miles are on the truck? do you have access to a scan tool? it usually on hits the low teens in my area and very occasionally we get near 0, either wya, when it gets in the teens i let my truck sit for 45-60 seconds with the glow plugs on before attempting to start. that extra 30 seconds makes a huge difference

 

Yep, cycle the plugs longer. Why did you only replace two GP's?

It should start without a hiccup if it's plugged in at night.

 

220K miles.

It fired up this morning without a hitch. It sounded like it was almost going to die, but didn't. I had it parked in the garage (not insulated) like I normally do, but turned the timer on before I went to bed. Temp was -6 when I woke up.

I replaced only two GPs cuz the other two were fine. I needed to save money. I measured their resistance with an ohm meter and they were both right around one ohm. The two I replaced weren't even registering a connection. This was the passenger side, so if the other two do go bad, it isn't a big chore to do. If it would have been the drivers side, I definitely would have done all four.

I might be able to get a friend to scan it for me.

 

How long did it smoke after starting it this morning?

What does the temp gauge read? How good is the heat in the cab? I'm wondering if, since you're getting prolonged white smoke, maybe the engine's taking too long to warm up - stuck open thermostat.

Dang, I was b!+c#ing at it being +7* this morning. Guess I'm glad I'm not in Frostbite Falls.

 

It smokes most of the way to work. It's about 15 miles highway, but short jaunts. I can't go more than about 3-4 miles without having to turn, stop or go up a big hill.

I don't think the thermostat is stuck open. Heat in the cab was a furnace two weeks ago when it was around freezing. The temp gauge SLOWLY (about 8-10 miles) rises to R, then drops pretty rapidly to N before rising back and sitting in the middle of O.

 

The water temperature readings sound pretty good to me. It's cold out... These engines having amazing cooling systems. In reality they are too efficient in cooler temperatures unless your working the engine.

Your smoke should clear up once your egt's hit about 300-400 (aka once the engine is under slight load).

What's your engine temp when you take off on the highway? Is it up to operating temp before you leave?

 

It's probably about 1/2 mile from my house to the highway. It is parked in the garage at night (not insulated). It is plugged and the timer is set to come on about 4am. I usually leave between 7:30am and 8:00am.

I don't usually let it warm up too much in the driveway. Never seems to really help much. Most days I have to drop my daughter off at school or drop the boys off at daycare before I hit the highway.

Before it started to get frigid, the smoke would pretty much clear itself up by the end of the block. Right now, once the engine warms up a bit, the smoke clears up at idle or while crusing. Accelerating or putting a load on it brings on the hoard of smoke. It seems that the engine is just barely getting up to a temp where it can burn off enough diesel not to smoke.

I went out to start it at lunch time (after sitting about 7 hours in the below 0 temps). It took about 4 or 5 tries to get it to run on it's own. When I first turn it over, it starts up just fine and acts like it's going to run .About 5-10 seconds later, it stalled. I let the GPs cycle for about a minute or so before I cranked it over. Tonight after work, as soon as it fired on it's own, I gave it a little on the pedal. It didn't stall at all after that.

I figure the two GPs that I replaced have been bad since I bought the truck last year. I had no issues with starting it last year (even at -15*). The only starting issues I had last year were with bad batteries and a bad starter. Absolutely no issues after those were replaced.

The fuel pump was replaced this summer along with the HPOP, RMS and Oil Pan gasket. Assuming those are good, I'm inclined to think my GP relay is bad or going bad? The relay doesn't seems to kick off earlier than I remember.

 

Are your filters clean (air , fuel)? The gp's will cycle for about 90 secs regardless of what the wait to start light says . I dont think the gp's are the problem they wouldnt cause it die or spudder after it starts running . Once the cylinders are warm enough to get combustion then the gp's jobs are done . Gp's dont continue to cycle or fire after the 90 secs is up . That sounds like a timing issue or fuel .

 

X2

Sounds oil related.

Bill

 

Oil related in what way? The oil and filter were changed about 5000 miles ago. Rotella Syntheic 5w-40. I didn't realize I was that far on the oil already.

Probably about time for a fuel filter and air filter. The air filter is probably really dirty. It's a K&N and I don't remember when the last time I cleaned it was. I am going to look into a 6637 mod instead of keeping the K&N.

The power steering pump has a tendency to whine ALOT when it's colder out. Could that be putting enough resistance on it to stop it?

 

Now that it has truly gotten cold here (-28* F this morning), I'm resurrecting this.

I replaced my air filter (old one was really dirty). That seemed to have helped, but it warmed back up into the 20s after I did that.

Now that it is truly cold here, the truck has started dying again at startup. It is not GP or GPR related. The truck turns over and fires GREAT. On first startup, it will actually run for about 10-20 seconds before it dies like the fuel has been choked off.

It may take 2 -4 times cranking it to actually get it to run. Each time, it fires, but will die almost immediately. I've noticed that the oil pressure gauge doesn't move until the 4th or 5th crank (when it finally stays running). When the gague does come up, then the truck will stay running.

When it does finally stay running, I get a horrible low pitched whine. It sounds like a power steering pump, but the steering wheel moves freely and it does not whine when I first start it up. The whine comes into play about the 3rd or 4th crank. As the engine warms up, the whine does go away.

I had the HPOP replaced this summer. I'm thinking the HPOP may be bad or is it simply that I need to change my oil (it does leak a bit).

So far, I haven't had the truck die completely on me. I just sold my 3rd vehicle, so I'd like to keep this one running.

96 7.3L all stock.