Ford F-150 - 1997-2003 :: Bad Miss Under Acceleration Below 2500 RPM
Dec 17, 2015
I have a 97 f150 with 4.2 4x4 auto. I have a bad miss under acceleration. if i ease on the gas no problems. stomp it and it chugs and pops back thru airbox til it gets to 2500 rpm then clears up. If I shift it manually and keep rpms up its fine till it gets below 2500. I have replaced spark plugs, plug wires, fuel filter, upper and lower intake gaskets, cleaned injectors, new air filter and cleaned o2 and mas sensors. Had vacuum system checked and was told all good.
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97 f150 4.6 4x4, no check engine light, no missing or sputtering, however when I try to get going I can't get passed 2500 rpm and when it finally does its still kind of sluggish and can't pass as easy. Changed fuel filter. It idles fine and when I put it in neutral it will go up to 5000 rpm if I want.
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2003 F150 5.4 72852 miles
I have a Rough Idle & sometimes a hesitation or stumble on acceleration. I cleaned the MAF & IAC motor & Air & Fuel Filters are new. I got a 20890 scanner & ran test 6 53 as suggested in many posts by BlueGrass. Here are My results & what They Convert to.
1 00F5 .3675
2 0051 .1215
3 0000
4 0000
5 00A3 .2445
6 0000
7 0000
8 0000
I'm guessing the cop's are ok & probably need plugs? I was hoping to just swap a coil. Too cold to do plugs & truck won't fit in my garage.
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My dad has a 2000 F-150 with the 4.6L with 90,000 miles. He just had the transmission rebuilt 5,000 miles ago if that. It seems to miss between 45-55 mph when you have a little hill and give it some gas. Once its shifts out of over drive, it seems to be better. With over drive off, it does not miss as much. I know we put new plugs in it but don't remember how long ago it was. He bought the truck brand new.
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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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My 01 Super Crew 5.4l is missing at light throttle. Cruise control on flat hwy, no miss, slight incline, starts missing. Put my foot into it and either it stops missing or it covers it up where I don't notice it. No codes set at this point. It's got about 135k on it and for all I know it may have had the original plugs in it so I figured I'd change them. Changed the plugs, still misses. Shortly a code set, something about the EGR sensor (it's got another name but I forget what it is at 1:30am). I found I had broken a hose while changing plugs, fixed it, no more code, still misses.
When I sent my GF up to get the non-existent codes checked the parts guy sold her some Lucas fuel system cleaner. I'm figuring a COP going out but the cleaner pretty much completely fixed the miss, till that tank of gas was gone. Few tanks later and it's back again as bad as ever. I bought some seafoam as I've had good luck with that in the past. It almost completely fixes the miss but I get a rare 'bump'. What do I need to look at next? Can it be the fuel filter? I'd think no because I'd figure it'd be even worse at greater throttle opening. Injector? How do I check them?
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I recently inherited a 99 Expedition 5.4 with 90k miles. I'm trying to fix it up so I can sell it. Like the title states, the truck runs rough but there's no check engine light on. I did some research and ended up replacing the PCV elbow and that made it run better for a while but now it's back like it was. It won't die, just a really rough idle and a miss while driving. I imagine it's probably a (or a few) coil pack(s), but I have no way of knowing which one(s) to replace. I would think that would illuminate a CEL though. I'm also having problems with the AC. Upon inspection, I found that the compressor clutch assembly was completely gone from the front of the compressor. I replaced the whole clutch assembly, then voided the system of Freon and refilled it to spec, still no cold air. The compressor clicks on and off like it's low on Freon but it can't be. I'd just sell it as is but in south Louisiana a working AC is a huge selling point!
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I bought a 99 f150 lariat 4x4 with the 5.4 from a guy who said that it needed an oil pump. He said it lost pressure coming into work, he turned it off and coasted in. I towed it home and replaced the battery and bought a new oil pressure sending unit just to be sure it wasn't that.
Those things are so hard to get to. Finally I got an oxygen sensor tool on it and it was only hand tight. Rather than take it off I just tightened it up and started the truck. The dash guage read normal but the truck was idling so badly. Steady at about 1000 rpm and tooth rattling. 1500 with the foot on the pedal it evens out but still rough. Not sure if this was a good idea but I took it around the block. No power under 2500 rpm. Barely moving even. Just felt like there was no throttle response at all and again very rough.
Got it home and parked it. Now I'm wondering what to do to fix the Idle and power problem. Where to start would be great. And input on the oil pressure sending unit too. I suppose I'll have to get under there and replace it at some point anyways.
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Alright so I have an 03 5.4 with 144000 miles. once it warms up to temperature it has a miss and low end power is low and no fuel mileage gets 12 to 13 if I'm lucky. From idle to 3000 rpm its doggy get it over 3000 rpm it runs great. All new plugs and coil packs. What it could be. When the motor is cold it runs great has most its power.
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I have a 97 f 150 with the 4.2 bad miss on # 6 changed plugs and wires still missing. Also have a bad tick and exhaust smells like fuel. Check engine light is blinking.
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My father's 2000 F150 5.4L has developed an issue. But the issue only surfaces in it's last gear. As it shifts into overdrive it begins to miss and hesitate and bog. If you disable overdrive you never feel it.
I'm thinking an exhaust restriction. There are no trouble codes, no check engine light. I notice that the note of his exhaust changes as the vehicle warms up, sounds like it's being smothered. And the flow out of the pipe lessens.
My only issue is whether the EGR is causing it or the converters. Haven't seen them go bright red yet, but this has been going on for a good while.
I wanted to get a few opinions before I tear into it today. I'll do a vacuum test on the EGR valve and rescan the codes but don't wanna drive it and heat up the exhaust when i gotta disassemble it.
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I have an 03 Camry LE with 80,000 miles I do all the maintenance myself it has had the alternator replaced once at around 40,000 miles. The problem that just started is a whistling sound that ONLY is audible after 2500 rpm at acceleration. When the car is in park no matter how much I revive the engine I can not get it to make the whistle sound it ONLY can be heard at acceleration after 2500 rpms.
Also once I cease to accelerate it goes away while I'm driving there is NO Whistling. I've read that it could be the alternator so I had it checked twice on the car and it checked out good it passed all tests. I've removed the belt and spun the pulley to listen for bad bearing but to me sounded fine. I've removed the throttle body boot and checked for cracks an found nothing also cleaned throttle body (not that it needed it) while I had it off.
Also checked air box and nothing. The only thing I've done recently was take out cabin air filter to clean and replaced it but there was no problem with that. What's puzzling is that it ONLY occurs at acceleration after 2500 rpms then stops after acceleration.
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Engine will start and run but will miss in a pull and die sometimes but will start back, we hooked it to a scanner and it said (intake wiring) it wasn't a dealer hook up just a gas station garage, we have already done plugs and wires.
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-My pickup was parked and hit in the rear axle in January. I had to have the whole axle replaced as well as the leaf spring to frame mounts.
-I finally received the pickup back and now when the trans is in Drive it will not up-shift until the rpms reach 2500 and it is a hard shift.
-Also the speedo does not work now.
-Check engine light also came on with code P0500- vehicle speed sensor.
-I replaced the VSS at the transfercase and the ABS sensor in the rear differential with no change.
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I have a new to me 98 F250LD with the 4.6/4R70W. I have maintained this truck fro my FIL as best as I could get him to spend (neglected). Filter and fluid replace with Mercon VI last year due to 2-3 shift slip.
He gave me the truck after it would not climb a hill, just hit stall speed and would not move up a steep hill, as I understand it. I put Seafoam trans tune in hoping it would free up sticky solenoids or valves in the VB.
I finally got it registered in my name and drove it to work and back today. After about 25 miles highway driving it shudders pretty bad trying to climb a hill at low speed.
It seems to me that at this low speed, torque converter lockup should not even be a possibility. I do not have COP, but rather a single coil pack. I replaced the wires and plugs for Dad a few years ago, but some shady shop later told him that I didn't replace the left rear (to make an upsale I suppose). Not sure what they may have done in there.
I have scanned with my ELM 327 and Droid using Torque Pro, and the only Fault is EGR flow.
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So my 98 f150 xlt 4.6 is having a issue where the truck is jumping from 1500 rpm to about 2500 - 2600 rpm. You know sitting there trying to get up to speed. then all the sudden i look down and its at 1500 rpm. but still not really going anywhere. So i give it a little more throttle or gas and it jumps from 1500 to about 2500. Its been like this for a month but i thought it was crap fuel. What is the cause or maybe a solution?
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1997 F150 4X4 4.6 engine with 285,000 miles
Truck was running perfect down the road, then suddenly it lost power and started missing at all RPM ranges. So i keep driving another 6 miles and then POOF the miss is gone and truck runs perfect. Couple hours later i hop back in it and its running good and then suddenly it starts missing and loosing power again except this time it never started running good again. Never did throw a CEL.
I hooked up my SCT Tuner (for my F250) to check for codes and came up with P0171 which indicated one of the banks was running lean, but no missfire codes. Did a search on here and learned the common problems(vacum leak) of that code.
Found the vacum leak at the PVC elbow, so i replaced both ends of the plastic tube.
Pulled the throttle body elbow and cleaned out the clogged up EGR ports.
Put a new air filter in and took the MAF out and cleaned it with MAF cleaner.
Put it back together and it idled way better but still ran like crap with the bad miss/sputter. Ran it down the road a few miles and came back thinking of the catalytic converter, i crawled underneath and it was glowing red. It does run and feel like the converter is stopped up but if i have a dead miss and dumping fuel wouldnt that make it glow red to or no? Still no CEL and now no codes.
Also i held the engine at about 1000 rpms where i could here the miss good and unplugged the fuel injectors one at a time to see if that made a difference. Each one i unplugged made it miss worse, so wouldnt that tell me that all 8 cylinders are firing?
And i changed the spark plugs (motorcraft) 250 miles ago.
So it still cranks and runs smooth after a cold soak overnight and then after a mile of driving or less it starts the dead miss/sputter and loss of power.
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My F150 with 175,000 miles on gave me a the ol' P0305 code indicating misfiring in cylinder #5. I changed the plugs and wires using Motorcraft wires and Motorcraft AGS34FM plugs.
Now the truck idles fine, does not give a OBD code but runs rough at 2,000-2,500 rpm. Tried it out on the highway and it started "bucking" a bit. Not sure what to try next.
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Noise on acceleration, sounds like a miss but engine feels good and no check engine light, eventually goes away, not there under a load either, idk totally stumped.
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My truck is developing a hesitation or a miss when accelerating. It only does it in the beginning of accelerating like when just starting off from a stop. Seems like its more noticeable with the more I get on it. If that makes any sense. When just lightly accelerating it doesn't do it, like going slow through town from light to light. But when I give it more is when I feel it. It seems like it only does it before the turbo kicks in and it puts out a little smoke too only before turbo kick in. After that it runs good with no noticeable miss or anything. WOT runs feel good after it clears up. Its just when first starting out with anymore that 1/4 throttle I can feel it.
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I posted a while back about my 04 5.4 having an issue at idle. I did all the normal things like replace coil, spark plug, etc etc. No change to the issue. It still acts as though it's misfiring on a cylinder and I get codes P0306 and P0316. Finally took it to ford and had a diagnostic check ran. Everything on the top end was in working order. The tech even put a known working coil on 6 and nothing changed. I was told that it's either an intake or valve issue on that cylinder. But no definite answer to problem.
Fast forward to yesterday. I got a wild hair at lunch and went out and started truck. Pulled injector plug off of 6. No change to the way it was running. I did the same for 5, 7, 8, 1, and 2. All of which made a big difference in the way it ran. It was obviously misfiring with no fuel to cylinder. This gave me the idea to swap 5 and 6 when I got home to see if the issue followed the injector from 6. I did NOT. I pulled the plug on 5 and got the obvious change in the way it ran. So there is definitely something going on at cylinder 6 that I cannot figure out.
PCM, bad intake, bad valve? I'm not rich so a trip to ford for repair is gonna have to wait. Truck seems to run fine when driving except for slight hesitation during acceleration.
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