I just bought a 96 F250, Ext Cab, 5spd, 2wd. It only has 95,000 km on it, so that's under 60k miles. Its been sitting so the diesel in it was old. I changed the filter, cleaned the FPR screen, changed the oil in engine and tranny. Drove about 300 miles after.

It still has a stutter sometimes at idle, even after driving and you push the clutch in, it will stutter for a couple of seconds, then idle normal. I don't think it sounds like a miss when idling normal. Tonight I was reving it up abit at a standstill, just watching the exhaust, and if I mat the pedal, it will rev up to 2500, then stop, then rev to 3k which is when I took my foot off the pedal. So I get a puff of black smoke, then white. Is this white just because I took my foot off, engine is slowing down and has unburnt fuel in the cylinder?

I checked for codes, and I have P0236, so from my reading this is pointing me to the MAP sensor. I will unplug it and see what come of it. Would that cause my 2500rpm freeze?

Any ideas on the intermittant stutter?

I used to have an 03 7.3 super duty, so I am somewhat familiar with these, but I bought this truck as my toy...hoping to get into upgrades in the next few months.

Thanks guys, looking forward to getting into a new forum.

 

a quick update, when I unplug the map sensor, and mat it in neutral, it will rev to 3k without much hesitation, but there are couple of "pops" from what sounds like passenger side, though it might just be in the exhaust.

With map plugged back in, it hesitates at 2500 rpm for a second as I described above, and then continues on. definitely feels like a miss.

Thing is, it doesn't feel like one when driving normally, just when you slow and push the clutch in, and it stutters for a second. Then it seems to normal out.

Thanks.

 

The RPM freeze sounds like injector orings

 

that would explain the smokd too?

why would o rings cause the hesitation? I'm not entirely sure where they are on the injectors...do you have a diagram or picture?

 

What you've got is an old truck with almost no miles on it. That means lot rot. If you've got codes and it acts better with the MAP sensor unplugged, replace that first since it's easy.

There are 3 o-rings on each injector. You can buy them, and see a diagram here Replacement O-rings for Ford Diesel Engines

It's much more labor intensive than changing the MAP sensor. I'd be prepared to do several different things as you get this back into shape.

 

Well I wouldn't say it ran better, frankly I think it runs OK...has less power than my 03, but I just though because it is older, smaller injectors, etc.

With the map unplugged, it would rev straight to 3000 rpm, but there were a few pops after 2500. not sure what those are.

Would the o rings make the white smoke problem? when it starts up cold, it smokes white for about 20-30 sec, not alot...I thought I maybe had a glow plug or 2 to change.

Yes, the valley is dirty, and the boots on the turbo are all covered in oily dirt. I was planning to tear into cleaning all that soon enough, and likely replacing boots, and maybe the turbo/plenum gaskets as well.

 

on a cold start DON'T watch the WTS (wait to start light) watch your volt gauge the glow plugs stay on for about 2mins. when they go off your gauge will go up and you might have a couple bad GP's or a GPR

 

the popping could be your fuel pump mine did that when the pump was on the way out the door check you fuel pressure,

 

I did check and it was at 55psi, I did the FPR mod and it went to 70. It was at 70 for all the results I listed above...

So what exactly do old or "not functioning" o rings do?

 

hey everyone, i'm new to the site as of today, i came across this post and it got me thinkin, i too have 1997 ford that didn't have many miles when i got it last year 100xxx which i consider few for a 13 year old truck, the lot rot thing got me. My truck has 127xxx on it now but for as long as i can remember it too sputters at idle when i first start it in the morning only about 30 rpms are gained quickly and then it goes back to normal and occasionally will shutter and lose 30-50 or so, it doesn't happen after the truck has been ran good. sometimes it seems like it's missing or something isn't flowing right, doesn't really sound like the other 7.3s i've heard, i got to thinking maybe it's the fuel, or the oil it has a descent leak near the water pump not sure whats leaking though because it doesn't lose oil, but the spot that's caked with dirt seems wet all the time and i never find oil on the ground that isn't from the lock nut or oil filter, i kinda live with it but i'm always thinking about it, doesn't seem like it's going to fail anytime but it would be nice to know why it's not runnin like a good 7.3 should. any help is much appreciated thank you all.

 

That does sound similar to my problem...I was pretty sure it was the old fuel, and clogged FPR screen, etc.

As I mentioned, I have oil or fuel in the valley, and it is on everything, but I know it wouldn't take much oil to attract the dirt. Hopefully I will get it cleaned soon enough.

If I do have to do orings though, it would be a good time while the turbo and fuel bowl are already taken off I'd imagine.

If you pull the valve covers, do you have to replace the gaskets? I suppose it's probably best to just change them, and the harnesses regardless.

 

sometimes it seems like its all in my head and nothings really happening, because in reality if the motor is running there are a lot of things working the way they should so in order to stop that something pretty serious has to happen, as far as i know you don't have to replace the gaskets you can if you want, it sounds like your motor might have a hpop leak in the oil gallery fuel pump leak or a leak in the oil coolant exchanger that's where i think mine is leaking at, but of course i don't know for sure if i get serious with it i'm going to take some brake cleaner and watch the motor run once it's clean, also maybe look into the cam position sensor there was a recall on those from what i've heard

 

since it had been setting I think heavy dose's of fuel additives like power service and clean or bebuild the Ipr and check the Icp too.

 

how do you clean these? where are they? do you just take them out and clean them off with degreaser? I did an oil change when I got it, drove about 500 miles, and I notice the oil is getting dark again. Maybe still some of the old stuff in the HPOP and other places, and I should do another change??

 

some one here can bring up some pictures and show how to do it better.