Hello all, I finally bought another Ford diesel truck. It is a 1993 F250 with a NA 7.3 liter diesel / Automatic. Only 132,000 miles and bought from the original owner who is in his 70's. Drives beautiful and strong. BUT When the truck is started when cold it puffs white smoke out the exhaust. The reason I did not worry too much about it is because my 88 F350 Dually did it when I owned it. This truck starts fine and runs clean (no smoke) when warmed up. What would cause the white smoke whe started cold??




Andy at Fort Hood, Texas

 

Welcome aboard!! Raw cold fuel. The winter seems to cause many problems that we dont see in the warmer months. Dont get excited it will change when the temps warm up. Just keep an eye on the coolant for a while to make sure there isnt any sneaking into a cylinder.

 

Yep,
Ya will get it every time you strart it cold. I have a 94 I just got an injection pumo in and it has allways done the white smoke thing when cold starting. That's all ot is. I think you will be just fine..
www.texashorse.net

 

OK, I have watched it and how it acts for a couple of days now and it smokes even warm if it is run at normal operating temp and shut off for 20-30 minutes and restarted. It is really thick sometimes. White cloud of smoke not just a little puff of smoke. Could it be worn, leaking or weak pop off pressure injectors? It seems to build up excess fuel after running and when restarted it has all that excess fuel sitting in the combustion chambers and makes a cloud of smoke. Has anyone else had this problem? What did you do to fix it? I will not just except it. Also, light puffing of white fuel smelling smoke at idle at most any temperature.

Andy at Fort Hood, Texas

 

I think you need to get your injectors pop tested. Sounds like they are not closing completely.

 

I just ordered a new set.

Thanks, Andy

 

My truck started throwing out blue/white smoke and it also has a loss of power, any ideas? I recently replaced all of the injectors and the injector pump was replaced two years ago.

 

Are you losing coolant?
Excessive white smoke may be your thermostat stuck open.

 

Veggeto08,
Welcome to FTE and the IDI forum.

What does the white smoke smell like?
Coolant would smell sweet.
Unburnt fuel would smell like fuel.

 

OK, here's yet another guy with the same white smoke on start-up issue. Based on other posts in this forum I realize that there are a number of potential causes. My 1990 sat unused for about six months before I bought it. I've had it for a month. In the first week it would choke the neighborhood with clouds of white smoke until the engine warmed up; then would blow some white smoke when I'd tromp on the accelerator. I read several posts regarding the benefits of using a fuel conditioner; I added it and after a couple of tankfuls the amount of smoke was dramatically reduced. I've kept up with the additive and the amount of smoke is maybe 25-percent of what it was when I got the truck.

A local diesel mechanic told me that if he were to replace the injection pump (for about $1000 that afternoon) I'd have a new truck; I decided to wait. Another mechanic said it was more likely to be an air leak in the fuel system. I bought the shop manuals for the truck, but I've found very little diagnostic help for this issue in those pages as yet.

The exhaust doesn't smell like coolant and the radiator level hasn't changed in a month. It smells rank and is very acrid, like unburnt fuel; even when it isn't smoking. I replaced two of the glow plugs that tested way out of spec. and they were covered with hard soot. They were the two that are a PITA to change since they're located under the injection lines.

Does anyone have recommendations on a step-by-step approach to diagnosing the cause for the white smoke?

Thanks,

Tom

 

How blue is the smoke?

If its blue it could be burning oil you may want to check and see if your turbo is passing oil.

If its white there are lots of good posts in this thread for that.

I will say that a few weeks ago my truck was blowing white smoke on mderate acceleration and some times even when I got on it hard. Started using diesel kleen in every tank and it cleared up. Why it didn't click in my brain to use an additive when I got the truck a few weeks befor I will never know.

 

Hello. This is my first post to this forum and I hope my recent experience helps... I have a 1994, factory turbo, 7.3, in an F250 with automatic transmission and 91,000 miles. I bought it in 2000 with about 70,000 miles on it, so you can see I didn't run it too much. Anyway, I developed a smoking problem that was very similar to many, many of the post I have found on this (very helpful) forum. I replaced injectors, caps and underhood return lines when I removed the engine to install a new oil pan. That was in early 2006. After putting it back together I still had the blue/white, raw-diesel-smelling smoke that was most noticeable when decelerating with slight accelerator pressure. I was convinced I had a worn out engine with low compression and, hence, unburned fuel. I didn't even put it on the road, but kept it, hoping to fix it someday. Long story longer, I found this and other forums and started to think maybe I had a bad injector pump. To confirm it, I decided to use a trick I learned on a Mercedes diesel forum (I have a 1983 240D). Here's what I did: I bought some cans of Diesel Purge (a supposedly highly concentrated cleaner/conditioner--there are probably others that would work. Maybe even DieselKleen.) I poured the cleaner/additive into a clean, 2 liter soda bottle and made a fuel supply and return line from clear plastic tubing. The supply line I connected to the lift pump and the return line I connected to the last injector cap on the rearmost, right side (removing the line that would go to tank and replacing it with my return hose). I secured the bottle on the passenger side of the engine compartment and inserted the loose ends of both fuel lines through the top so they both exteded to the bottom of the bottle. I also cut a small "X' near the top of the bottle so I could insert a funnel and add fuel as needed.This created a fuel tank that removed the possibility of air intrusion between the stock tanks and the engine. The clear lines allowed me to see if air were still getting into the system somehow. I ran the truck on 100% Diesel Purge until my "tank" was nearly empty. No smoke and the engine seemed to run smoother, but still wasn't right. The fact that there was no smoke meant I wasn't burning oil or coolant. The next step was to replace the Diesel Purge in my homemade tank with clean, fresh diesel. It went back to smoking. I went inside and ordered a reman injector pump. I installed it last week and am happy to say my truck has never run better. The only thing I wish I had done prior to ordering the pump would have been to try adjusting the timing of the original pump. But I'm not complaining...

 

Thats a good Idea. another way to check for air intrusion would be to hook up a fule presure gauge with a clear line going to a jar when you push the presure releas buton if the fule comeing out has bules you got air.

The thing with the botle is pretty ingenuitive and eliminate a lot of lines so you can isolate the problem.

Fullcircle I dont get why it wouldn't smoke with the additive do you know the reason for that? Just curious

 

George D.

My guess is that it is a more highly refined fuel and, therefore, burns "cleaner" even when conditions (injection pressure, compression, timing, etc) are not ideal. Diesel requires that minimum conditions be met or we'll get smoke.

 

That makes sens