i have a 2001 f350 7.3.
I know I have a few bad injectors, the truck hafly ran but no in cranks cold (lost of white smoke) chokes rattles a bit for the bad injectors, but will run for about 27 miles bogs down and kills out. come back 2hrs later fires up and off for another few miles. today I bypassed the fuel tank using hose from the pump to a 5 gal jug, it ran about 10 miles and died. b4 it died it blew tons of white smoke and choked out. other than the injectors what could be my problem? weak fuel pump? and why all the white smoke??? please someone help. also I changed the cps just incase that was the problem and it did not help. anyone have any ideas were I need to look next?

 

It really sounds like fuel starvation. You should check your fuel pressure before moving on with any further diagnostics.

 

This is good advice. Could be caused by a lot of things. You may want to invest in a $50 fuel pressure gauge to check your pressure pre-filter and then post-filter. You simply move the gauge from the rear driver's side upper port on the fuel bowl to the lower port on the passenger side.

What could cause it? Yes, a poor fuel pump could do it. Or, a sticky Fuel Pressure Regulator (FPR) which is about $20 to replace. Or, your fuel filter in your fuel bowl could be really clogged up if it hasn't been changed in years. Better yet, BENEATH your fuel filter in the fuel bowl could be filled with sediment, I have seen that numerous times. Or, perhaps the post inside your fuel bowl that the filter rides on has a valve in it...sometimes they have been known to stick. You can gut this valve as all it does is prevent fuel from flowing if the bowl lid isn't screwed down (it uses downward pressure from the fuel bowl lid on the fuel filter to activate).

I would usually also mention a clogged screen in your tank, but you said you ran from a bucket bypassing your tank, so it's likely something from the pump forward.

Before you check any of this, check your oil level. If the dipstick is ultra low, you could have lots of problems.

Then again...maybe it's your injectors as mentioned. If you know several are bad, well, maybe the time has come to rebuild them. Certainly, it wouldn't hurt to pull your valve covers and watch your engine running with the covers off to see which injectors are flowing right. Before you run the engine, torque the injector and rocker arm bolts to the proper specs to make sure none are too loose.

 

Check the IPR and see if the tin nut is on the back. a few years ago mine did kinda the same. turned out the IPR went bad

 

Check IPR % and ICP pressure if you can. Also check for oil in the coolant.

 

Ok thanks guys . Ill start checking all that stuff but what's up with clouds and clouds of white smoke at low rpm ? It only smoke when its stuttering and chokeing/ rite befour it kills out. Also why can I come back when its cold and it fire rite up. What scenser could cause that?

 

My truck did the same thing when my injectors went out. At first I had a misfire that would come and go. Then right in the middle of the road it died and would not start back up. After i had it towed to the dealer i got it to start and you could tell there were a couple cylinders not firing. I don't remember which one's but I had 2 bad injectors.

 

X2 on low oil being a good possibility. I don't remember having white smoke, but mine did the same thing years ago before I realized how crucial oil level was, especially in the 7.3. Extremely low oil causes low fuel pressure symptoms.

 

ok, i filled all oils and coolant to the max. engine oil and hpop. I still have the fuel tank bypassed, I swaped the icp with a known good one. also replaced the cps. now the truck turns over fast like its about to fire up but it will not run at all. BIG NO NO but I tried to start it with starting fluid and still nothing but turning over and tons of white smoke. the #8 injector does not work at all, but I drove the truck 200 miles with no problems other than rough idle and what sounds like spark knock every once and awhile. but now nothing at all. could the Ipr be causing this problem? all it does is turn over really fast almost to crank and blow smoke. you would think it would run a moment on starting fluid. anyone have any other ideas?

 

rpm tach move when cranking? No way of finding out what the icp is seeing while cranking?

 

Running while cold but not when hot is one of many possible symptoms of low fuel pressure. My previous post talked about what to check on that.

It sounds like you know what the problem is...one or more bad injectors. Sounds like it's time to rebuild your injectors, install new injector cups, and heck, while you're in there doing all of that, you might as well replace the valve springs too.

 

im getting about 150 rpm when cranking, the truck wont start at all, I know only the #8 injector is bad. it seems to me that its not getting enough high psi oil. it wants to crank but just cant get there. theirs no way the other 7 injectors went bad at the same time. it ran fine at first with a spit and sputter, till it got hot thin died, let it cool and it would crank, no it wont start at all.

 

How low was the coolant and oil ? What does the white smoke smell like unburnt fuel or coolant ? You do have the batteries charged up right ?

 

Speaking of batteries charged, Once, Mine cranked perfectly, But only at 10.2 volts. Ran both batteries up to autozone to test and i had a dead one. Replaced under warrentee.. It was weird because it cranked fine, just won't fire.

 

I highly doubt it's a low fuel pressure problem. If he wasn't getting fuel he wouldn't be getting white smoke. My fuel pump went out and I got a SES light and noticed my boost was lower then normal. 3 minutes of trouble shooting and I figured that out.