Hello, I have a problem with my 1995 f250 4x4 auto 7.3.

I bought the truck with this issue (previous owner never told me) so I'm not sure when the problem first started.

The issue I'm having is a random no start problem with white smoke while cranking also sometimes the truck will randomly shut off when driving, like I turned the key off. Dosnt bog out. Also appears there's a fuel leak from the valley but only when the truck is running.

So far I've replaced the cps with no affect and the tahc reads while it's cranking, tried unplugging Icp with no affect, checked harness by the bottom of air box, cleaned fuel bowl, new fuel filter and finally replaced under valve cover harness and connecter, also with no affect.

I don't think it has to do with glow plugs, when it will start, it will no problem even when cold. What makes me really believe it isn't the glow plugs is last time this issue happened I was driving around in the truck for about 45 minutes with no problems, truck was at operating temperature. I shut the truck off for about 5 minutes to talk to my friend and when I tried to restart it just cranked and cranked blowing white smoke. Wouldn't even try to fire. Had to get it towed.

Whats really strange is that when the truck is running it doesn't smoke, has lots of power, and overall runs perfect. I also don't have a cel but im going to try scanning the truck tonight for the hell of it.

Any help would be much appreciated as I am not driving the truck now because I'm to affaid it will leave me stranded. Thanks for looking.

 

Your no start with white smoke could be the glow plug relay. The contacts in the relay get burned spots on in, and when the burned spot aligns rite you get no contact to allow juice to get threw to the glow plugs. Some high mileage engines/injectors need just a little more heat to get them to fire off. This might be the case with a no start when warm. When the no start happens next time, you can bridge the 2 large bolts on the top of the relay with a screwdriver, or some other metal, for 30 seconds. Take care not to touch any thing metal other than the 2 large bolts. If the truck fires up, the relay is bad.

 

Thanks for the reply. I will try that next time it won't start. That still wouldn't explain the random shutting off problem that I'm having though, I think the random no start and shut off are caused by the same problem but I could be wrong. Also I should have mentioned my truck has 200,000 kilometers (125,000 miles) on it.

 

Did you use a ford cps or a parts house off brand? Check wiring to cps and wiring to ipr for wear or bare places. Make sure the nut on the ipr is tight.

 

I think I used a Dorman brand cps if I remember correctly. I'll check those things tonight and report back.

 

Parts house sensors have been known to not play well with our trucks. Ford sensors are the normal go to.If you get one from ford parts house it is only about $ 28 IIRC

 

Yes after I check what was mentioned above I will replace it again with a motorcraft or international one.

Another thing I forgot to mention was the truck came with a edge evolution tuner. The old style that looks like a game boy. From reading other threads, people were saying that these tuners don't work well with the obs trucks. I don't know what they mean by that. I haven't seen anybody list the specific problems that one of those tuners could cause. Could this be part of my issue?

 

From what I have read a chip can cause problems like you describe. I do not know from experience , I have a program on my pcm. If someone will confirm my thought, I would pull the chip and see if the problem goes away. May be someone else will chime in with more knowledge on that chip.

 

So tonight i got around to messing with the truck again. checked the tin nut it was tight, also checked cps wiring, all looked good, checked fuel pressure at the tire valve thing 15 psi when cranking (forgot to check when it was running) I scanned the truck tonight also and I had these codes:

P1280: ICP CIRC OUT OF RANGE LOW

P0603: INTERNAL CTRL MOD KAM ERROR

P3044: CAMSHAFT POS SENS CIRC INTERM. (BANK1/1 SENS)

P0340: CAMSHAFT POS SENS CIRC ERROR (BANK1/1 SENS)

Now correct me if Im wrong but im pretty sure I have the icp sensor code from when I tried running the truck with it unplugged. And the Internal control module code is from when the computer reset after unhooking the battery cables a few days ago? To me this is pointing to a new, but faulty aftermarket CPS like somebody mentioned above.

The weird thing is that when the truck is running there is no check engine on. I had the CEL when the icp was unplugged but after I plugged it back in the CEL went away.

I really appreciate the replies, this is my first diesel and this is all new to me. Nobody I know seems to know anything about these trucks either so this is the first help I've had with this problem.

 

aftermarket cps are not good on these motors. A new motor craft would be the next step

 

Yes Tomorrow I am going to the stealership to get a new cps. I will install it tomorrow if they have one in stock and report back.

 

Well my motorcraft cps came in today at the dealership. Installed it tonight and once again, nothing changed. I'm stumped. This truck is really testing my patience lol. Do you guys have any other suggestions for me?

 

15 psi is way to low and the pressure should hold when the truck is off, for a long time (over night)
you also mentioned that fuel leaks in the valley while running it sounds like you issue with restarting is from low fuel pressure and or air intrusion. You will have to see where your fuel is leaking from and go from there.

 

Better off just replacing that glow plug relay amyway. Most of us use that big ******* Stancore or Western Plow unit. Fresh GPs too if unknown age and brand. ZD11 Ford only.

Hard starts can be from weak or undersize batteries along with a beat starter. Been there and done that. Clean the battery terminals too, corrosion on lead cannot be seen. Good thread on here for that.

Mechanical fuel sucks. E-fuel it and never look back.

Basically baselining the truck is what you need to focus upon too.

 

Fuel pressure does not hold when the truck is off. What should the pressure be when cranking? I thought I read 15-20 psi somewhere. I never tested the pressure while running yet.