Ford 7.3L Power Stroke (1999-2003) :: 2000 - Occasional Miss At Highway Speeds / Bucking And Jerking During Even Gentle Acceleration
Jul 28, 2015
165k miles 4x4 6 speed, bone stock unmolested
Slowly progressing problem over 6 months. Occasional miss at highway speeds uphill has progressed to bucking and jerking during even gentle acceleration attempts.
I hadn't got my cam sensor recall done but no change after that procedure completed yesterday. Oil recently changed as well.
I have a torque pro but it never finds any fault codes even though 'service engine' light comes on sporadically. I'm not sure I'm operating it properly but it at least reads rpm when its running.
I'm contemplating the hutch mod but I'd like to have an official diagnosis beforehand if its possible in my case.
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I have recently picked up an older F350 2WD 7.3 DRW Lariat. the price was right higher miles but hey it is a 7.3, overall in very good shape.
So the issue at hand is the truck runs great most of the time and puttering around at city speeds you would never know there is any issue;
Get the truck out on the highway set the cruse at 70 to 72 and if you hit a rise in the road or other reason to slightly accelerate the truck chugs and bucks. For lack of a better description it goes chug chug chug, if you accelerate harder to downshift it goes away or if you back off the throttle it goes away. This happens with cruse on or off, a steady foot on the pedal will cause this as well.
I have also noticed that when you let off the throttle the sound the truck makes de-fueling is just very different and "off" sounding . Not sure how to describe it but it sounds funky ... clearly not right when compared to other 7.3 or my 6.0 truck.
What I have done, :
1. Had the truck scanned with an AE and a snap-on scanner both show no codes ran injector tests no contribution errors, not even in # 8.
2. Changed fuel filter
3. Changed Oil and Filters ( tried both full synthetic Rotella and Dino oil looking for a difference )
4. Cleaned out the fuel filter housing just in case.
5. Confirmed injector O-Rings are not leaking
This feels like a fuel issue, my next thought was start looking at fuel pressure under load at speed to see if there was a drop when this is happening ?
Is there a way to test fuel pumps in this truck ? Maybe a clogged pick-up screen ? Where do I start looking next ? I have reasonable mechanical skills but don't know this motor very well, this doesn't seem like a CPS issue..
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Got a strange one here. 1995 Buick Park Avenue, supercharged 3800, 159K miles... an older car, but an unmolested one. A little over a week ago I began to notice an occasional miss when cruising along at highway speeds, along with a slightly rougher idle. Both the fuel filter and the plugs/wires predated my ownership of the car (a little more than 6 months); so seeing no obvious culprit, I replaced them and hoped for improvement.
Unfortunately, neither had any impact. The missing continued to become more noticeable. It was never present under acceleration. Most of it was like a split-second long version of "bucking" that could be observed while cruising at lower (<2000) RPMs. It was also very noticeable at idle. Eventually a code was set: P0341, camshaft sensor issue. If the story had ended there, it would have been just another night in the garage. But it didn't.
As I was noticing the aforementioned symptom increase, I also noticed my voltmeter would occasionally "twitch" in the downward direction. Eventually I had an incident where I came to a stoplight... transmission in Drive, foot on brake, gauge dropped to around 10-11v. It returned to 14v momentarily, but dropped back down, held there for several seconds, returned, etc. No particular rhyme or rhythm. Of course my first guess was that the alternator was failing; a separate problem from the other.
I checked all the relevant connections (at the battery, at the alternator, etc), and cleaned them for good measure. All were tight, relatively clean, and the cables showed no resistance on the ohmmeter. It happened that I had another correct alternator on hand (used/working pull), so I swapped it in. No change. I reinstalled the original and was back where I started.
On my most recent drive, I noticed both issues had become very noticeable. The drop in voltage was happening at nearly every stop, and the missing was happening a few times per minute while coasting along. There seemed to be some correlation between the missing and voltage fluctuating, but it wasn't absolute.
I decided to attack the voltage issue again. Re-checked all the cables; same result as before (all OK). Looked all over the car for possible bad grounds, loose connections, or other visible problems, but found none. My next thought was to run a jumper from B+ to the voltage regulator's Sense input (have seen issues there on more than a few older vehicles) - but after reading that this car uses the PCM as the voltage regulator, I didn't proceed.
Just to be certain I'm going to have the alternator tested by the local auto parts store. But I suspect it'll pass.
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2000 Ford Excursion, 7.3 PS with 210,000 miles. I am on I40 at a truckstop. I was rolling down the freeway last night when the truck started bucking. I pulled of the freeway and here came a thunderstorm. I waited til this morning to check for codes cheap scanner. I pulled a code P1211. I waited for NAPA to open so I could take it in the shorts. I bought a fuel filter and an ICP sensor. After changing them out, the truck runs then starts missing. My battery is about to die so I will finish post shortly.
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2000 F250 7.3L ZF 6spd 4x4 regular cab long bed 253k
DP F6 chip, 4" exhaust, WW2, EBV delete
I run 5w40 Rotella Synthetic. Oil was changed about 1,000 miles ago. I also added a quart of Hot Shot stiction eliminator. I use Power Service and Stanadyne lubricity in every tank. Fuel filter is new.(motorcraft)
For a month or so its been acting weird. I get a stumble/miss/stutter, at random, but mostly under hard acceleration and high rpm (specifically approx 2500-2800rpm). It will also do it on decel when I lift after accellerating . Recently, I noticed it is also idling roughly. The engine is shaking and it feels like a miss. When it does its "thing" it sounds like a single "knock". Occassionally, it sort of sounds like an injector "buzzing". I've been using the "stock" tune for the last few weeks, to minimize any chance of engine damage, as I have to drive it. Turning up the chip makes the problems more noticeable and happen at a lower rpm. The truck has plenty of power, and pulls hard, except for the "stutter". If I hold my foot in it to "push through" the initial stumble at 2500 or so, it will keep going a few hundred more rpm, and then really start bucking.
There are no meaningful codes. I DO have:
EBV related soft codes - makes sense since its deleted.
Overboost related codes- from turning the chip up - won't happen in stock setting
A soft code for the back pressure SENSOR. I have a new one and will be cleaning the tube when I get a chance. I unplugged the sensor and it made no difference in the miss issue.
I have recently done the following in pursuit of a solution to all this:
New IPR (autozone) valve and pigtail
New ICP (motorcraft) and pigtail ( sensor had oil in it)
New CMP and pigtail. (2 actually. First a standard pc139 for the obs, and currently a Napa echlin correct for '00) No change. Although it initially had the dreaded Ford small head light grey sensor and failed cct for #3 & 8. After the cps change, it passed cct.
Accellerator Pedal Position Sensor. It would not read any higher then 3.95v at wot, and only 0.50v at idle, so I installed a new one. After adjusting it a little, I have 0.76v at idle, and 4.02 at wot. Didn't affect the stumble issue, but it seemed to greatly improve/eliminate my parking lot speed "bucking".
I just did the UVCH's. The passenger side was pretty much unplugged. But they all looked good. No burnt, melted,or chafed wires anywhere. I probably could have just plugged it back in, but I changed both sides with new Motorcraft parts anyway. I did the gaskets and the uvch, but not the engine side harness/pigtail, as they looked ok. I also did the 0.50 mod as a preventative measure. After seeing the unplugged harness, I really thought this would be the end of the problem, but its not. Very frustrated.
As a side note, I was surprised to see that I have 8 AD injectors, and not an AE in cyl 8.
I have an old outdated snapon scanner. Its only good up to '99, but I am able to scan my 2000 as a '99. I think I'm missing some pids though.
I can do cct and buzz test, but no PERDEL readings.
As far as ICP, it idles at about 450psi, at approx 12% IPR dc. On a brief 2nd gear wot run, it will hit (and hold as long as I have road to stay in it) a little over 2900psi, at 41-42% IPR duty cycle. I did notice, during these near instantaneous stumble events, ICP would flutter on the scanner about 75-100psi. Its almost too quick to even see it.
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I'm a mechanic but work only on cars so I'm a little shy on diagnosing trucks. I have a 2001 7.3 f250 4x4 short bed, when I give it gas I can hear a clunk, when I let off of the gas I also hear a clunk. Also when traveling at high way speeds I can feel a strong vibration when I very lightly give it gas but the vibration goes away as I give it more gas.
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I have a 45 min drive to work every day, all highway. Lately on the way home in the afternoon I have been experiencing a surging noise that seems to just happen while I'm doing hwy speeds. It sounds to me like the fan is tuning on and off. Is that possible? It comes on for a few min. And then off again. I have new icp ipr cps. New oil and filter and fuel filter.
Also I'm still having a battery light on and off issue while I'm driving. Is possible the two issues are connected. I plane on doing extensive search for a bad wire this weekend. Batteries and alternator have checked out and are fairly new.
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I have a bucking and jerking 6.0 right now. It will buck and then won't go above 2000 rpm or it will lurch or if I hold the pedal down lose power unless I drop it below 2000rpm. If I put the pedal down the truck wont go above 2000 rpm and will go up on speed. the erg was deleted but its trowing crazy amount of white smoke from the exhaust. When the truck starts up some white smoke comes out but eventually clears up when you keep it under 2000 rpm.
When on idle you can step down the pedal and hear the truck failing on revs like an injector issue but i checked and they arent the problem. the problem got fixed for a couple of weeks when i changed the Y pipe because the other was ruptured but the problem came back and its even worse now i can use the truck for nothing.
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I have a 1999 F350 200,000 miles. Now getting an intermittent engine light. Still runs well, although once or twice I felt a momentary surge at highway speeds. The light is on intermittently about 1/2 time. I read the codes and the following codes, as in the thread title, came up:
P0280 - ICP circuit out of range - low
P0113 - intake air temp sensor circuit - high input
P0470 - Exhaust back pressure sensor circuit malfunction
P0478 - Exhaust pressure control valve - high input
What would make these all code at the same time? Would these not make a noticeable problem driving? And how do I resolve these?
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I have a strange noise that occurs at both highway and surface street speeds. On surface streets at low speeds 45 mph and under, if I let off accelerator to coast and lightly step on accelerator I get this quick sharp noise.
Everything I have read regarding a similar noise is under load and being described as a turbo fart. Clearly I am not under any load. I'm lost.
Definitely not a low woooo noise. Also not a hard accel and release and definitely no chuckle and or popping. The sound is high pitched and quick, roughly .5 to 1 second at most. The sound is more like a "zzzrrp" or "zzzoop". I can replicate the sound 50% of the time easily at speeds under 45 mph by briefly coasting (no accelerator) and lightly tapping the accelerator and releasing or holding. Occasionally this sound will occur at full stop when I step off of the brake pedal and before I step on the accelerator. This sound can also occasionally be heard at highway speeds under similar accelerator conditions though it may be more frequent and I just don't notice it.
Would this condition throw a code? Just received "Total Ford Scan Tool Package Enhanced Bundle SP03" scanner from autoengenuity. Hoping to put it through its paces tomorrow.
Additional info: 145k miles. Injectors serviced by a reputable diesel shop here in Vegas approximately 1.5 years ago. Unknown oil leak where oil is collecting in the valley on top of the engine beneath the turbo. HPOP seals were replaced roughly 1 year ago at another reputable diesel shop here in Vegas. Still have an oil leak (turbo related?) Oil is under 500 miles old and acceptable level. Fuel filter is due for a change but that does not seem to affect condition. Air filter 1000 miles. Thinking about upgrading to AIS severe duty kit soon.
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I've got a 2003 Ranger 2.3L DOHC, 5 speed, 2WD. It has a check engine light with codes :
P0316-Engine Misfire Detected On Startup
P0704-Clutch Switch Input Circuit Fault
P2195-O2 Sensor Excess Lean Signal Bank 1-Sensor 1
P0171-System Too Lean (Bank 1)
The truck runs fine when coasting or accelerating but when holding a steady light throttle to maintain speed the truck starts bucking and jerking. It's doesn't feel like a misfire, more like a fuel cut out condition. When this happens and you come to a stop, you can smell that the exhaust is very rich coming out of the tailpipe. I've already replaced the upstream O2 sensor and I did a tune up about 15k ago. I'm thinking fuel pump or fuel pressure regulator. I doubt if this is related, but on start up (more so on a cold start up) the A/C compressor clutch kicks in and out 3-5 times and makes a terrible racket.
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I have a 2000 with a six speed and through the first 2 gears while giving it only a little throttle, worse on hills and worse while towing I have a pretty decent vibration. Once you get to 3rd and up its fine. I have read about axle wrap and due to the fact my springs are pretty wore out I think this is a big part of it. Any other things to look at other than new springs? The u joints all look and feel fine so I haven't touched them.
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So, I was on my way back home driving through the middle of nowhere Utah late at night, when I had an injector tip crack. I was able to identify which one and unplug it so I could get to Grand Junction, CO (about 350 miles away) where I have family. After a power nap I started calling parts stores and found an injector from Advanced Auto Parts (I couldn't find a motorcraft reman, but I was restricted for time). Installed it and all seemed good so I hit the road again. However, nothing changed. It still had the bad miss (rough idle, jerking/bucking when the torque converter locks up) just like when I had the injector unplugged.
The truck is an early 2004 6.0. It's the number 4 injector. I finally got home and hooked up my AE scanner to discover a #4 injector circuit low P0270 code and circuit contribution/balance fault P0272. It's definitely missing because disabling it has no effect. This could be a loose connector at the injector or FICM, because I can't afford another injector right now.
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I have a new to me 2005 F150 SuperCab Lariat 4x4 with 155,000 miles on it. About a week ago I replaced the from passenger hub assembly and half shaft (torn boot). When doing that, I noticed that the IWE actuator was not working right (would not compress evenly). When taking that off, there was a bunch of rust that came out of the vacuum line ports. It started moving freely after cleaning all of that out that I could (I will be replacing it soon). I assembled everything back together and all seemed OK mechanically.
I also scanned the truck and saw the code for a bad IWE solenoid so that is being replaced tonight. I also have not checked the drivers side yet.
So...now that I have done all of that, the truck started occasionally bucking/shuddering when I slow down from highway speed to about 30mph and lightly accelerate again. It does not do it every time though. There is no grinding/whining noises either. Could this be caused by the IWE system somehow? Maybe slowing losing vacuum and having one engage and the other disengaged?
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So here's the deal: My 2000 F250 has began to have the overdrive light blink when I am traveling at low speeds <40mph and it is accompanied by strange shifting (lower gear for a longer period of time). As soon as I get up to highway speeds the blinking stops and goes back to normal operation. But as soon as I go back to low speeds it happens again. When I put the truck in to park when it has the light blinking it revs it self to about 1200rpms then goes back to normal idle. This truck has 228k miles and is on the original transmission.
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2003 f-350 6.0 4wd dual rear wheels
4 inch superlift suspension lift, dual shock steering Stabilizer
33 inch wheels.
4 inch turbo back exhaust
Other than that it's really bone stock
Here's what's going on. In 2wd, between 55mph and 62ish mph, once I hit a constant speed, a rumble beneath my feet emerges. If I either speed up or slow down, it immediately goes away.
Does the same thing in 4wd high.
I can eliminate front drive shaft and u joints seeing as they shouldn't be turning while in 2wd. I did notice that when I push up or side to side motion in the front drive shaft, there is a click and a bit of motion. Is that normal? Just a side thought.
When i take off there's a bit of vibration from the rear half of the truck, but I've isolated that to the center support bearing. With all this being said, none of these symptoms were around before I lifted it.
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Have a 03 f350 with the 6.0 have been experiencing very harsh shaking problems. This only happens at highway speeds 55-60 any other speed is smooth as can be weather it's 25-95 mph. The weird part is that it only shakes when the truck shifts into overdrive and it shakes bad and if you lay into it like you were gonna pass someone it stops then shifts back into overdrive and shakes again.
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I have been having a problem for a while now where my truck will miss/buck at WOT. This only happens at higher RPM's. From a standing start 0-60 it is fine. However when I downshift full throttle from about 50 MPH it initially goes, but then it will miss/buck consistently until I back off the throttle.
I have so far replaced the CPS, re torqued injectors, checked valve cover harnesses and fuel pressure stays in between 64-58 full throttle. No codes show up.
My truck runs great except as I described above. I would think an injector or two are bad, but the truck runs and idles great. My initial guess was that it was a fuel pressure issue, but fuel pressure holds strong. Could it be air in the fuel?
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My mechanic told me that the fuel pressure is about 5psi low. Could this cause jerking/bucking during acceleration?100,000mi SS
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If I don't keep her plugged in she starts hard, bucking etc. I'm thinking GP or GP relay but I`m not getting any thrown codes. Talking about *30-*50 outside, when its warm starts normally.
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I want test my fuel pressure. What is a good gauge or kit to buy? My truck has lost power towing and is now starting to miss a little. I'm wandering if i my problem is in the tank. Is there a good scan tool that would diagnose things too?
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