2000 exp w/code P0174 runs roughly and stalls constantly help?

[kellyandtheboys]

My 2000 exp, 350k miles, is showing code p0174 at autozone. A little history...truck was meticulously maintained since "birth" by my father. He gave each and every detailed record/receipt to me along with the truck 1yr ago. The truck has been running extremely rough for a good little while now. It stalls randomly in idle and now, even when Ive been driving. I have kept up with maintenance and repair as needed. I just replaced the battery and alternator.

Autozone suggested for me to replace cyl #8 (ignition coil), use a fuel injection cleaner, and replace spark plugs. Im in a desperate predicament, as I am a single mom. I need to drive it to work an hour away 2moro. I am leary about their feedback and can't afford to waste the parts I bought. Any suggestions, thoughts, advice is much appreciated. Can I easily handle the ignition coil thing myself?

Thanks for your help!

 

[Copper93]

Does the idle bounce at an idle? If so, try cleaning the throttle body. They get carboned up and will cause a stall at idle and a bouncing idle. Normally a 300 code is a coil or plug. Also try cleaning the mass air sensor, that can cause the same issues. Start with the easy stuff and work up.

“A code P0174 may mean that one or more of the following has happened: The MAF (Mass Air Flow) Sensor is dirty or faulty (if equipped). Note: The use of "oiled" air filters can cause the MAF to become contaminated if the filter is over-oiled. There is also an issue with some vehicles where the MAF sensors leak the silicone potting material used to protect the circuitry. There could be a vacuum leak downstream of the MAF sensor Fuel problem (rail/injectors/pump/regulator)”

Read more at: https://www.obd-codes.com/p0174
Copyright OBD-Codes.com

 

[BRIANGEE]

I agree with the throttle body cleaning. The MAF cleaning is a freebie also but without some scan tool data for Direction everything is more or less a guess. Bank 2 refers to the driver side of the engine for this vehicle. More than likely you probably have a vacuum leak. You can feel around the plastic hoses and see if any are brittle or deteriorating and replace as necessary. Do a search on YouTube for finding vacuum leaks as there are a few different methods and find one you feel comfortable doing. If you do happen to find a vacuum leak and you need your vehicle in a pinch you could alway put a few turns of electrical tape around any holes - depending on the circumstances though. I would also suspect the IAC (idle air control valve) or even EGR.

If you can gain access to a scan tool that reads live data we can help you gain more Direction by evaluating that data. Your local Walmart probably has an autel for $40 that does that.

https://www.walmart.com/ip/Autel-Au...75035&wl11=online&wl12=48180423&wl13=&veh=sem

 

[JExpedition07]

Yes, the replacement of ignition coil on cylinder #8 can be tackled yourself. The little bolt on top should be a 7 or 8mm, remove that then pull the coil straight up. A rubber “boot” will come up with it, pull that off, and spin the metal spring out of the old coil, spin that spring into the new coil and put the boot on it. Cylinder #8 will be the drivers side rear cylinder.

 

[kellyandtheboys]

Thanks for comments posted. I do have the printout from autozone regarding the error code. I will post below. Also, I forgot to mention in original post, the vacuum hosing was replaced already.

 

[Joseph3]

My 2000 Expy 5.4 was recently reporting the same code. It was running rough. It was indeed the #8 coil pack, I put in new plugs, cleaned the MAF sensor. Running great now.

 

[1955moose]

Maybe it's just me, but when did P074 trouble code turn into #8 coil? Was I absent that day? I thought misfire cylinder#8 was p0308! Am I missing something here? All the advice our members gave you are sound. I would hold off on changing that coil. Clean the throttle body, and the Maf sensor. Just be sure you or whomever is doing it uses proper sprays. The other thing that's cheap enough to change is the pcv valve hoses, and elbow. They also get brittle, and cause symptoms and codes like yours.

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[Engineer1225]

My 2000 exp, 350k miles, is showing code p0174 at autozone. A little history...truck was meticulously maintained since "birth" by my father. He gave each and every detailed record/receipt to me along with the truck 1yr ago. The truck has been running extremely rough for a good little while now. It stalls randomly in idle and now, even when Ive been driving. I have kept up with maintenance and repair as needed. I just replaced the battery and alternator.

Autozone suggested for me to replace cyl #8 (ignition coil), use a fuel injection cleaner, and replace spark plugs. Im in a desperate predicament, as I am a single mom. I need to drive it to work an hour away 2moro. I am leary about their feedback and can't afford to waste the parts I bought. Any suggestions, thoughts, advice is much appreciated. Can I easily handle the ignition coil thing myself?

Thanks for your help!

Check the ground wires coming from the ECU just to be safe ( check ALL the ground wires if you have the time, there's a couple of them), check for corrosion on them and clean it off. You'd be surprised at how much chaos bad grounds will cause. If you plan on keeping the vehicle, I'd recommend buying the Ford DVD service manual online. The DTC chart it has you'll fine EXTREMELY useful. I'd tell you to check the fuel pump relay but you're not getting the "secondary fuel pump circuit" error, so I didn't mention it.


I looked up the sections pertaining to your problem and the service manual states:

"H41 DTCs P0171, P0172, P0174 AND P0175: FUEL SYSTEM AT THE CORRECTED FUEL TRIM

• 
  Note: It is necessary to address all Continuous Memory Ignition and Misfire DTCs, if received during Continuous Memory testing, before addressing any Fuel Trim DTCs.
  
  Fuel System DTC Reference List:
  • Bank 1 = DTCs P0171 (lean) and P0172 (rich)
  • Bank 2 = DTCs P0174 (lean) and P0175 (rich)
• Check intake air system for leaks, obstructions and damage.
• Check air cleaner element, air cleaner housing for blockage.
• Verify integrity of the PCV system.
• Check fuel delivery system and filter for restriction.
• Check for vacuum leaks. "

-----------------------

HA41 DTCs P0171, P0172, P0174 AND P0175: FUEL SYSTEM AT THE CORRECTED FUEL TRIM

• 
  Fuel System DTC Reference list:
  • BANK 1 = DTCs P0171 (lean) and P0172 (rich)
  • BANK 2 = DTCs P0174 (lean) and P0175 (rich)
• Check intake air system for leaks, obstructions and damage.
• Check air cleaner element, air cleaner housing for blockage.
• Verify fuel level.
• Verify integrity of the PCV system.
• Check for disconnected spark plug wires.
• Check for vacuum leaks.
• Verify customer did not run out of fuel

------------

P0174 - System to Lean (Bank 2) The Adaptive Fuel Strategy continuously monitors the fuel delivery hardware. The test fails when the adaptive fuel tables reach a rich calibrated limit. See Possible Causes for DTC P0171. See Diagnostic Aides for DTC P0171 "
------------

P0171 - System to Lean (Bank 1) The Adaptive Fuel Strategy continuously monitors fuel delivery hardware. The test fails when the adaptive fuel tables reach a rich calibrated limit. For lean and rich DTCs:

• Fuel system
• Excessive fuel pressure.
• Leaking/contaminated fuel injectors.
• Leaking fuel pressure regulator.
• Low fuel pressure or running out of fuel.
• Vapor recovery system.
• Induction system:
  • Air leaks after the MAF.
  • Vacuum Leaks.
  • PCV system.
  • Improperly seated engine oil dipstick.
• EGR system:
  • Leaking gasket.
  • Stuck EGR valve.
  • Leaking diaphragm or EVR.
• Base Engine:
  • Oil overfill.
  • Cam timing.
  • Cylinder compression.
  • Exhaust leaks before or near the HO2Ss.

A SHRTFT-1,2 PID value between -25% to +35% and a LONGFT-1,2 PID value between -35% to +35% is acceptable. Reading beyond these values indicate a failure.

 

[1955moose]

Wow I need to take a shower after reading all that! If your going to fix your Expy yourself, you need to narrow down all that hoo-ha, that our friend engineer 1225 shot your way. The trick to narrowing down 2 pages of diagnostic material down to 3 or 4 things, separates, and excuse me for this the men from the boys. One thing that dealer and dealer equipped mechanics, and shops have to shorten the list is technical service bulletins. Basically their things that pop up a lot for the same customer's complaint.It saves the tech a lot of footwork, and that's what we're trying to narrow down a myriad of items down to a few. Hope that helps. You start with the most common of that code, and work outward from there. What I was taught a million years ago in Automotive school, was start with the cheapest, or better still free, then move to your more expensive fixes. Never tell a customer he/she needs an engine when spark plugs/carburetor might fix the problem.

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[slow96z]

I know I'm late to the party, but I just resolved this same rough idle, stumble and dying on mine yesterday. There is a PCV boot at the back of the throttle body base (I think) that tends to get a big hole on the inside corner of the 90' bend. The Dorman part number is 46017 and the local parts store had it in stock. I hear that this is VERY OFTEN a massive vacuum leak. You won't be able to see it, but if you get on top of the engine, straight back past the throttle body you will see the IAC motor, a little to the right of center on the back of the throttle body. Feel below and to the left of that for a rubber boot that will have a hose heading left towards the passenger valve cover. Manipulate the bend in that boot and see if it's mushy, sticky or soft. If it is, that's probably your issue and it's about an $8 fix.

It looks like this:


I hope this helps you out!

 

[Tonyray]

Check the fuel pressure it may be the fuel pump or the fuel filter. You can check Autozone for lend-a-tool for a pressure gauge They charged me $150.00 plus tax but you get all your money back when you bring the gauge back. Mine was 20 PSI and it should be 30 to 40 PSI.

 

[Joseph3]

My 2000 Expy and I were up in Washington state when the same thing happened to me. It wouldn't stall out completely, just was running very rough. I went to AutoZone and got the same story you did. It was the same code P0174 and the guy told me exactly what the guy told you. Cylinder 8 misfire, replace the coil pack and spark plugs. I was skeptical too. Long story short I replaced the coil pack and it totally resolved the problem. The spark plugs looked pretty bad so I replaced them too. It now runs better than ever. So sometimes these AutoZone guys are right!
I admit I am confused why the manual says code P0174 is a fuel problem. Definitely not a fuel problem in my situation.

 

[Joseph3]

In the interest of full transparency, a shop actually replaced the coil and plugs. Should have said "I had the coil and spark plugs replaced" instead of "I replaced...). Also, in the shop diagnosis they said they swapped the 8 coil pack with the number 2 pack. A new code was generated to indicate a cylinder 2 misfire. So the problem followed the bad part.

 

[stamp11127]

And ****, another one bites the dust. Where did she go?

 

[cdahlen]

To clean the throttle body which spray cleaner should be used?

 

[1955moose]

One that says throttle body cleaner right on the label. I posted this earlier, but I'll reiterate, how can a p174 code turn out to be a failed #8 coil? The computers not designed to register that #code for something like a coil, or sparkplug. That would be like in the past using a big Sun scope, and get no spike in kv reading on any 8 cylinders, and then have a bad misfire that turns out to be a bad spark plug wire. It just makes no sense. How did the first person that changed that # coil, know to go to #8, and not 6 or 7? If they changed all 8 like so many do, how would they know which one fixed the problem. That would be shotgun part changing. Anyone here with more gray matter than me got an explanation? I'm all eyes/ears.

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[98eb5.4]

as mentioned, a specific issue on cyl8 brings up a specific code, sounds like u got bad advice,

1st thing i'd look for with a p0174 is a vac leak, a breach in that system (buncha hoses) alone can cause major engine running issues, that might be nothing more than reconnecting 2 hoses together

i think u continued to drive it that way for some time & now it's worse, it could be that there are other codes now & i'd check that too

My 2000 exp, 350k miles, is showing code p0174 at autozone. A little history...truck was meticulously maintained since "birth" by my father. He gave each and every detailed record/receipt to me along with the truck 1yr ago. The truck has been running extremely rough for a good little while now. It stalls randomly in idle and now, even when Ive been driving. I have kept up with maintenance and repair as needed. I just replaced the battery and alternator.

Autozone suggested for me to replace cyl #8 (ignition coil), use a fuel injection cleaner, and replace spark plugs. Im in a desperate predicament, as I am a single mom. I need to drive it to work an hour away 2moro. I am leary about their feedback and can't afford to waste the parts I bought. Any suggestions, thoughts, advice is much appreciated. Can I easily handle the ignition coil thing myself?

Thanks for your help!