Ford F-150 - 1997-2003 :: Rough Idle / Engine RPMs Go Up To 2k Before Dropping Down
Mar 23, 2014
1999 F250 LD with 5.4 w/ 225k miles... Was running perfect yesterday when I shut the engine off. Started back up about 20 minutes later and Idles was up and down and rough.( 400 - 900 rpms) Drove and ran fine except Idle. I know that those codes are for the o2 sensors but don't believe they're bad. I hear what sounds like a vacuum leak somewhere behind throttle body. Either IAC or EGR or it could be coming from the line that runs in beside the IAC valve to the air intake in front of the throttle body. Tried spraying water in those areas with no results. Could it be a bad EGR valve or a stuck IAC valve? I have also noticed that lately when I start the engine the engine rpms go up to 2k before dropping down. Would a bad IAC valve cause such rough idling along with the codes that I described?
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I have a 2000 F-150 5.4 L. I was driving from home and seconds after the engine went into a rough idle that wouldn't let me accelerate. I scanned it and gave me multiple transmission trouble codes, about 15. I checked the wiring, the transmission fluid and it all looked good. So, what could be the problem?
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Bought the truck knowing it needed a little work because it sounded like a diesel when running. So I had the timing chain, tensioners, water pump, etc. replaced and that fixed that problem. Then, a couple days later, a spark plug blew out of the engine. So, I go to do a full tune-up to find out that 3 of the 8 cylinders already had heli-coils in them.
I pulled those three and bored out and re-tapped the cylinders using the Cal-Van inserts. This has worked beautifully so far. I also replaced all of the other plugs as well with double platinum plugs. I also replaced all COPs. This got the truck running again and it drives great. No loss of power whatsoever. It just runs like a dog at idle. As soon as I give it throttle it smooths out completely.
It seems like the problem gets worse as the engine starts to get up to normal operating temp. Basically, if I am idling, in gear or in park, the truck shakes pretty bad. It kind of feels like it's starved for fuel or barely missing. I do not have any codes though and if it is a miss, it is completely gone under throttle.
Other things I have replaced within the past couple of weeks:
EGR
EGR vacuum solenoid
DPFE
Both PCV elbows
PCV valve
Air filter
Harmonic balancer
Other things I have done:
Cleaned IAC
Cleaned throttle body butterfly (including EGR ports)
Checked TPS voltage
I'm sure there are other things that I am forgetting.
The idle seems low to me but I'm not sure what is considered standard for the 5.4l. Mine idles around 600 in park once engine is warm and the needle doesn't move despite the roughness felt. Just going by the tach, you would think that the idle was smooth as silk.
Truck info:
2000 Ford F-150 XLT
5.4L V8 2V
150k miles
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I am having a problem with my 1997 f150 4.2 v6. The engine is running rough at idle and while driving. It's running so rough that it vibrates the entire cab of the truck. I found water in the oil when I was trying to fix the problem. I have since had the heads redone and replaced all of the gaskets thinking this was the reason for the rough idling and rough driving. It wasn't; doing this fixed the water in the oil but still I have the rough running engine at idle and driving.
I have replaced the EGR valve, plugs and wires, pcv valve, replaced the coil pack, fuel filter and air filter (everything has been replaced with ford recommended parts because I have read that the engine I have doesn't like after market parts). While driving the engine vibrates and sound as if it's going in a cycle in a rhythmic sort of way (like a washing machine goes in a cycle), best way I can explain it. I have come to the end of what I think it is?
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2001 5.4L 4x4...Engine bought from reputable junkyard with 140K has new manifold studs, motorcraft spark plugs, and 8 coils (bought on Amazon).
No check engine codes...checked for vacuum leaks...And has rough idle.
Is there a reason it might have rough idle aside from blown motor? The mechanic was going to take it to get computer reflashed but not trying to throw money down the drain...
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I started out with my 2000 F150 with a 5.4 V8 running rough at idle. It would idle way down slow and then rev up a little over and over. On a couple of occasions it would even die when in drive or reverse. I did finally get a Check Engine light so i put it on my diagnostic program to see what was up. Here is what I got:
P1151 Lack of HO2S21 Indicates Lean
P0171 System Too Lean Bank 1
p0174 System Too Lean Bank 2
After doing some reading up I checked all my vacuum hoses and cleaned my mass air flow sensor. I then got the same codes again after a few minutes of running. So I went to the next thing that was recommended, the upstream bank 2 O2 sensor. After changing it the truck ran fine for a couple of days, no issues. Then all of the sudden it idled a little funny again and I got a Check Engine Light again. This time:
P0171 Bank 1 Lean
P0174 Bank 2 Lean
P0300 Random/Multiple Misfire
I reset the light to see if I would get the same again later. Before the light came on again I filled my truck up with gas and it seemed to be running pretty good again. Then a day or so later it set the light again. This time:
P0171 Bank 1 Lean
P0174 Bank 2 Lean
P0136 O2 Circuit Malfunction Bank 1 Sensor 2
P0156 O2 Circuit Malfunction Bank 2 Sensor 2
P1131 Lack of Switches HO2S11 Lean
P1151 Lack of Switches HO2S21 Lean
I went ahead and drove for a few days as it had gotten really cold here and I didn't feel like messing around in my shop since it isn't heated. A couple days ago I needed gas so i filled up again. Suddenly the problem was gone again. Truck ran fine idled fine no missing or odd idling at all. That lasted a day or two before it started acting a little weird again. At that point i was down about 1/8 of a tank from full. I have read that there can be issues with the fuel pump.. I am kind of wondering if that may be it now. But I haven't had to deal with this sort of issue before so I am unsure what to check next. The truck always runs fine off idle, it only seems to have the issue when it is idling. I had reset the codes the last time and i have the light on again now. I haven't checked it yet but I am sure it is going be some combination of what i have had in the past.
I have read that the IAC valve can be an issue as well. I had a problem with mine sticking a couple years ago and when it would do it you could just tap it with a wrench and it would idle up. But it never died like it does now and it would also idle a lot slower than it does. Back then I cleaned the valve and had no more issues with it. The truck has always had times when it would act weird at idle usually after slowing down after being at highway speed. The current issue happens at all temps cold or hot.
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My trucks symptoms include a illuminated service engine soon light, sometimes a high rpm idle, and sometimes a rough erratic idle. When a scan was done it indicated the oxygen sensor was defective. The issue is: which specific one (there are multiple oxygen sensors) or how could I check or determine the faulty one for sure. I am trying to economize and replace only the bad one myself if possible. I own a good multimeter, can it determine the bad one? 1999 F-150 4.2 Litre V6 oxygen sensor dillemna....
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Twice now this has happened to me and I'm concerned it will become worse if I don't fix it. Driving down the road my engine has disengaged. By this I mean the vehicle both times has been at 55 MPH, my foot on the throttle rpms riding around 1300 revolutions, and the engine disengages rpms drop below idle and my "wait to start" light comes on. This both times lasts approximately 2 seconds and throttle reengages while still traveling 55 MPH, "wait to start" light goes off and its like it never happened. What's going on with my truck? Ford diesel 97 250 7.3 ...
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So my "farm truck" is idling very rough, to the point that sometimes that it stalls out. At high idle it runs fine but when its at a idle its very rough. Its been running fine until probably a month ago or so and its just getting worse. What it could be? I am thinking it might be that something is dirty but i just dont know where to start with figuring out what the problem is.
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2010 F150 ... So I have the tick noise at rpm's 800-1000 at drive through, stops, etc. So I did research on it a few months ago and saw that it might be VCT's but should be able to drive. so I drove it waiting to save money and have it go to a shop. well this past weekend while coming home from work my oil light came on the pressure dropped to zero, I was on the highway so I drove about another mile to get off highway and once I got off my truck died. I had it towed to my house and I thought I blew my motor. So I started doing research here and found that the VCT's AND cam Phaser could be bad. so I replaced my VCT on driver side put it all back together it started and loud knock was gone. then after 5 mins it was back very loud knock!
So I shut it down and took apart the passenger side once I got the valve cover off I found the problem.... The bolt that holds the cam phaser in place snapped off and was riding along the camshaft. So I took that out and extracted remaining part of bolt. inspected my camshaft and it was really messed up. so I bought new Phaser and Camshaft. the camshaft just came in today and I am trying to put it back in. but the hole for the pin in the phaser doesn't line up and I cant spin the shaft to make it line up. should I spin the cam phaser? I marked the chain and the phaser is where it should be on chain, but with that bolt snapping off could that have thrown the timing off so my mark is no good? when I lay the camshaft in place it sits perfect and if I just move the phase over 2-3 links it will all fit together. Should I do that?
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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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RPM's are dropping way off when coasting downhill while towing (as if the motor shut down), CC is on and maintaining desired speed. When at the bottom of the hill, all of a sudden, with a big bang(in the motor) the rpm's have came back up and you drive on down the road as normal. This seems to happen only when towing. "99 F250 7.3 I haven't pulled any codes as of yet. Whats happening?
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I recently started noticing that when I am coming to a stop(usually a quick stop), the trucks rpms drop to low. hard to tell how low but looks like around 450-500 rpms. I can feel the truck struggle just for a second then the rpms bounce back to 650-700. i was sitting in my truck while in park and was revving up to about 1200 and then let off the pedal and it died. My positive battery terminals are getting pretty bad and am going to replace them soon(waiting on parts). Could this be the cause?
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1997 Subaru SVX (Alcyone) LSi, 3.3L H6 engine.
My SVX was driven from Denver to Las Vegas, NV and it developed an odd habit where the RPMs would start to oscillate while on cruise control. I had to disengage the cruise control to get the oscillations to stop. Three days later I was driving the SVX to work and the RPMs started oscillating at idle and the car started running rough and it died.
These things have all been replaced with OEM grade parts: Spark plugs, electric fuel pump & strainer & fuel filter, Mass Air Flow sensor, new air filter and fuses.
The car starts up fine but after a few seconds the RPMs begin to oscillate. Then the car tries to recover, the idle becomes rough, and the the RPMs drop very low and the engine shuts off.
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Random rough idle about every 30 seconds at low 700s (rpms) and it'll bounce up and down a little. The code was p1515 (No CEL or other lights have come on yet) which is something about the intake manifold valve and there is an air-shooting noise that is pretty loud but just sounds like air that's being lost somewhere like maybe a leak and that happens when i rev right before you can hear the engine rev the air/shooting noise occurs. I don't really think I'm losing power but I got the car recently so maybe I am and don't notice it. If this is a common leak or something with the intake manifold valve let me know,
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I just acquired a 2003 with 5.4 L. Did all new plugs and coils, cleaned MAF sensor, changed air filter, oil, transfluid and filter (obviously not related).
Upon start up and idle the truck has is rough, enough that it will vibrate the whole truck SLIGHTLY. Once in gear and warm, it smooths out and is fine. Unit the next stop and start.
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I got a 97 f150 4.2l from my neighbor. he takes good care of his vehicles. he sold it to me cuz it started to idle very rough like a misfire. it is hard to start when cold spits sputters and pops. once started idles like it wants to stall, then will idle normally then back to rough. back and forth like that. runs like a champ when going down the road . check engine light was on took it to auto store they checked codes . said bad o2 sensors so i changed them. still same issue. neighbor changed coil packs checked spark plugs and wire. every thing fires good. i changed iac. still didn't fix problem. could this be a bad egr valve or sensor? if so how can i diagnose this? he also thought was a clogged cat and bored it out. tight budget can't afford to take it to a mechanic. Was told spray carb cleaner spray around engine to check for leaks that did nothing at all...
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I bought this truck used and when it's in drive the engine idles rough and seems about to stall when the ac is on at a stop sign or red light.. I've tried it w/o the ac on and it seems a little better but not as smooth. Idle in park is fine.
When I should start looking? Spark-plugs? spark plugs wires, disturber cap, fuel filter etc...
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2000 Ford F150 1/2 ton 2x 5.4L... Last year, I started having a problem where when the temp dropped below 50 degrees outside, my F150 would idle really rough and sometimes stall out. The CEL came on and reported some codes that I don't remember but pointed to bad air/fuel mix. I consulted a friend and he suggested changing out the IAC. I did that just towards the end of the cold weather spell we were having and the engine ran great so I assumed it was fixed.
Well, the temps have been below 50 for 8 days now and ever since the temps dropped the problem has come back. I took it to AutoZone to have the codes read and they gave me the following:
P1151 - Lack of O2 switches -bank 2 sensor 1 : ECM could not adjust fuel trim because of a lean or rich condition
AND
P0171 - Fuel trim bank one condition : The powertrain control module uses the oxygen sensor to calculate the Air/Fuel ratio of the engine. The computer recognized a rich or lean condition on one engine bank only.
Both printouts that they gave me mentioned the following:
Poor fuel pressure
Bad or Malfunctioning MAF sensor - Dirty/defective
Oxygen sensor defective
Fuel injector problem - Leaking or fuel pressure high/low
Vacuum leak on engine
I again called my mechanic friend and he suggested cleaning the MAF and if that didn't work replacing the MAF. I cleaned it and the problem was better but still not fixed.
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I recently picked up a 2wd 2002 F-150 with a 4.2l V6 that has just over 300k miles. The CEL is on and I'm getting P1131, P1151, P0316, P0305 and an occasional P0301. It has a very distinct misfire from around 1,000 rpm and smooths out between 1,500 & 2,000 rpm, the idle rpm occasionally bounces (sometimes enough to stall), and the idle is sometimes rough.
I have replaced the plugs, wires, fuelfilter, and replaced a leaking PCV hose. As I have changed things the symptoms have improved some but they are still there. While capturing some livedata it kept going out of CL and into OL Fault. When it would the idle quality was crap and the miss was much more significant. I would have to put it into D hold the brake and run the RPM's up to just over 1k to get it back into CL.
After I got done with the data stream at idle, I set the parking brake held the foot brake and put the truck in D then ran the rpm's up to around 1,200 & held it there. The truck stayed in CL but it would cycle between misfiring for 5 - 10 seconds then clear up and run smooth for 20 ' 30 seconds, every time it cycled there was an audible click that could be heard. Also, the AC was off the whole time.
Live DataStream @ Idle: CL
CalculatedLoad Value - 12.9- 14.1%
EngineCoolant Temp - 103degrees C
Short TermFuel Trim B1 - 32.8%
Long TermFuel Trim B1 - 0.0%
Short TermFuel Trim B2 - 32.8%
Long TermFuel Trim B2 - 0.0%
Engine RPM - 816 . 846
[Code] .....
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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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