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P030X Random Misfire & Limp Mode Questionaire and Discussion Thread

What solution was administered to address your P0300/Limp Mode Issues

  • Cam Sensor(s) replaced

    Votes: 0 0.0%
  • Wiring Harness replaced

    Votes: 0 0.0%

  • Total voters
    28

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zzyzx

Steve
299
0
Re: CEL - "random misfire" (recurring)

Ok, time for a possible helpful update on new findings.

I went out today to put more break-in miles on the Boss (at 980 now), and have figured out the exact conditions that throw the CEL.

In 4th gear @ 4000-4200 RPM (around 60 MPH) for about 10 seconds or more, causes the CEL to start blinking. Upshifting to 6th to bring the revs back down, and the blinking CEL goes away in about 5-10 seconds. At this point it either turns off, or stays on. If this is the first run after a code reset, the CEL seems to simply turn off. If you let the car sit for a hour or so, then go back out and reproduce the same behavior, the CEL stays on. All codes to date are just P0300.

I've paid close attention to all the various noises the Boss makes, and it's pretty obvious that right around 4000 RPM, the engine has some distinctly noisier harmonics at play. My guess is that this is what ultimately leads to the misfire detection.

Note that I haven't once actually felt anything when this happens; no hesitation, nothing.

The current engine in my race car also has a "noisy" region in the RPMs that has lead to false knock detection. The stand-alone engine management system has a sophisticated set of parameters to adjust that can help avoid these false positives. I had to datalog the sensor inputs and graph the raw knock sensor values against RPM to figure this out. Once identified, I adjusted the parameters to suit, which worked.

All that said, this doesn't necessarily reduce the possibilities of what could be the root cause, but it is great to now have identified a repeatable procedure to demonstrate to the Ford dealership as well as to do as an after-fix litmus test to confirm that the issue has been resolved.
 
Re: CEL - "random misfire" (recurring)

That's interesting. There is a noticable "bog" at 4000 RPM in the Boss under moderate throttle. Drew (ArizonaGT) explained this in another thread but I can't remember the details. Hopefully he will chime in but it had something to do with a transition point in the way the cams work on our car........
 
Re: CEL - "random misfire" (recurring)

4th Gear... 4,000 RPM... 60 MPH... Hmmmmmmm, sounds vaguely familiar to me ???

All the same parameters that caused my replacement engine to start throwing the P0300/P030X codes on the 75-mile drive home from the Dealership...

But luckily, I just passed the 400-mile mark today on the total break-in mileage, without any codes since performing the "Neutral Profile Learn Procedure" at my local Dealership...

And just curious if anyone knows the "official" answer from Ford as to what exactly the 2 black foam NVH insulators are intended for? Are they there for "looks" and to help keep the intake valley free of debris? Or are they actually designed to help dampen all the extraneous noises & vibrations that might be erroneously detected by the knock sensors... Inquiring minds want to know... THANKS!
 

zzyzx

Steve
299
0
Re: CEL - "random misfire" (recurring)

Ok, here at the Ford dealer waiting for my rental car.

Took the service manager out for a ride and demonstrated everything to him, and said he "felt" the misfire.

This is the first time I've actually felt a rough misfire. Brought it up to 4k RPM in 2nd gear, blinking CEL, then stopped at a red light. As I sat there, the idle was rough enough to shake the car. Stayed that way through the red, and about 30 seconds afterwards, then cleared itself up.

I handed him a short write-up of what you've all posted here and he read it and attached to the service paperwork.
 
Re: CEL - "random misfire" (recurring)

4000 RPM in 4th gear is when my CEL's are happening as well - at least the 8-10 or so I've been able to gather freeze frame data on. Unfortunately, I cannot recreate mine on demand.

The car ran a little better at NJMP (Lightning) yesterday. Only got 2 CEL's on 2 out of 5 runs. I made a concious effort to stay off the rev limiter, only hitting it once or twice all day. This seemed to help, but given they are happening at 4000 rpm there is defintely something else going on.
 

zzyzx

Steve
299
0
Re: CEL - "random misfire" (recurring)

UPDATE:

Ok, dealer was able to reproduce the issue repeatedly in their testing. They did a "reset" of the PCM which I believe is the "neutral profile learn" or something similar. He said that after this, the misfire counts dropped drastically and he was about to call it good. Two drive cycles afterwords when the service manager when out for a test (after the tech did the same), the flashing CEL re-appeared.

They have a call in with Ford engineering on next steps.

KBBOSS1086 - I'm certain you can reproduce the CEL. You need to drive on the highway for a good 10 minutes. Then repeatedly cruise in 4th @ 4100 RPM. My guess is that the counter needs to reach a certain value before the flashing CEL starts appearing. Once you get to the point it'll flash, getting it to flash again takes far less drive time. Also it seems to take two drive cycles of this to go from an intermittent flashing CEL to a solid CEL that stays on.
 
Re: CEL - "random misfire" (recurring)

zzyzx said:
UPDATE:

Ok, dealer was able to reproduce the issue repeatedly in their testing. They did a "reset" of the PCM which I believe is the "neutral profile learn" or something similar. He said that after this, the misfire counts dropped drastically and he was about to call it good. Two drive cycles afterwords when the service manager when out for a test (after the tech did the same), the flashing CEL re-appeared.

They have a call in with Ford engineering on next steps.

KBBOSS1086 - I'm certain you can reproduce the CEL. You need to drive on the highway for a good 10 minutes. Then repeatedly cruise in 4th @ 4100 RPM. My guess is that the counter needs to reach a certain value before the flashing CEL starts appearing. Once you get to the point it'll flash, getting it to flash again takes far less drive time. Also it seems to take two drive cycles of this to go from an intermittent flashing CEL to a solid CEL that stays on.

OK, here we go again... Just finished putting 1,000 "break-in" miles on my replacement engine over the weekend... 500 around-town miles right after the swap and just took her to a car show 250 miles from home for the remaining 500 miles this past Sunday... Dealership performed the "Neutral Re-Learn" procedure right after I brought the car home... Seemed to "fix" it until I went for some longer drives...

Still getting P0304 after driving on sections of road where I can maintain approx 60 MPH at 4,000 PRM in 4th Gear... Happened once on the way over and once on the way back... Never when cruising around town and never when motoring down the Interstate between 70-80 MPH... However, I can easily replicate the CEL on a country road 2 miles from my house...

After triggering the code this AM, I swapped the coil packs between #1 and #4 hoping that if the CEL did come back, it would show up as MISFIRE on the #1 Cylinder instead of #4... Therefore, it would be a simple replace of the faulty coil pack... NOPE! Still shows as a #4 Cyl Misfire???

Have to swing by the Dealer this afternoon for a tube of RR touch-up paint... Not sure what they can do to fix it, since it does appear that only a certain set of parameters is what actually triggers the misfire... Maybe a unique vibration at that particular RPM and engine load???

EDIT ~ Just went to Track Attack last Tuesday... And my car for the day (Orange #4) started out with a steady CEL when I first sat in the car to adjust my seat and the racing harness... Would periodically go OFF and then come back ON during the afternoon Track Sessions... Went into Limp Mode 2-3 times, once with my Instructor in the Pass Seat wondering why I wasn't going FAST enough???
 
Re: CEL - "random misfire" (recurring)

That's weird. I was getting a "check charging system" my last 3 sessions at BIR a couple weeks ago, but so far nothing street driving it for over 2 weeks. I didn't even bother taking it into the dealer since it won't replicate itself, but odds are it will show up in a couple weeks when I'm back on track. :-\
 
Re: CEL - "random misfire" (recurring)

cloud9 said:
That's weird. I was getting a "check charging system" my last 3 sessions at BIR a couple weeks ago, but so far nothing street driving it for over 2 weeks. I didn't even bother taking it into the dealer since it won't replicate itself, but odds are it will show up in a couple weeks when I'm back on track. :-\

What's even "wierder" for me, is that I never got a CEL during the original 3,600 miles before the engine replacement??? I drive on the same roads and at the same speeds as I'm now getting the CEL for #4 Cyl Misfire... Go figure???
 

zzyzx

Steve
299
0
Re: CEL - "random misfire" (recurring)

Unfortunately, I don't have any meaningful update on progress right now.

07SGT0547 - I'm actually glad you're able to reproduce the CEL under the same circumstances. Bottom line, though, if you don't take it in and tell them - like I did - "this is how you reproduce the CEL" - and pursue it, then you're stuck with it. Now that said, I realize you already have a "history" and have replaced an engine already, but I would still pursue it.

Hopefully (crossing fingers), my situation will result in a fix that can be applied to other cars. We'll see. I'm working with a very competent service manager, and at this point he's committed to doing what it takes to resolve the issue. No BS, no run-around.

My best guess at this point in time is one of the following:

1. Bad crank sensor.
2. Out of tolerance tone ring.
3. Out of balance flywheel/clutch assy.

FYI - The crank sensor and tone ring are attached the to flywheel on the back of the engine, not the front. Their next step is to examine the tone ring and sensor with a boroscope (not that that'll tell you if a tone ring is our of tolerance by 10-30 thou of an inch...).

Also keep in mind that Ford Racing has already designed a new tone ring because the current design doesn't work well @ high RPMs. So there is possibly a precedent that the current design is "marginal".

I can "hear" the noise differance @ 4k RPMs, and that's where the the issue happens. So I imagine it's possible that an out of balance flywheel/clutch assy combined with a possibly out of tolerance tone ring and "false positives" from the PCM and that could be the root cause of the issue.

The first step, though is to figure out whether this is a case of "false positives" and PCM S/W programming OR a real physical issue in the drivetrain.
 
Re: CEL - "random misfire" (recurring)

One thing I will say, is that after the engine swap, I now notice a LOT more drive-train "noises" than I did before... Even with the MGW shifter already installed (w/Heat Shield and all the Sound Deadening), there wasn't as much "harshness" with the OEM engine as I notice now???

Even had a fellow 2012 BOSS owner drive it, more for the feel of the MGW upgrade, but he even commented on how much more engine noise mine had than his...

Wifey even asked why the car was noisier driving down the highway??? And she has ridden with me several times BEFORE & AFTER the engine swap...

So I know it's not just me being paranoid and hearing every little noise from this new engine... Also seems a little rougher when I give it the gas to pass someone while in the 6th gear... Feels like there isn't the same power as there was before... Almost "flat" when you press the gas pedal...

My thought as well, is that something is out of balance... Not on purpose, but when put back together, maybe there is something that is just a little "off"... Especially when I can easily replicate it under a certain set of driving parameters... And more so, since neither the recurring P0304 code or the engine noise/roughness was present with the OEM engine in place...

Oh and this NEW engine has already used 1/2 qt of oil in the first 1,250 miles... No oil consumption during the first 500 miles (shorter drives in urban areas), but has steadily dropped to half-way between the dots on the dip stick during the last 750 miles (mostly highway driving)...
 

zzyzx

Steve
299
0
Re: CEL - "random misfire" (recurring)

UPDATE:

The tech removed the crank sensor to do an up close inspection - they found no obvious issues with the sensor.

After putting it back in the problem no longer occurs after pretty extensive testing.

So, the only physical thing that was disrupted was the circuit from the PCM to the crank sensor. It's possible that either the connector wasn't seated well, or the sensor itself is marginal.

A new crank sensor should arrive soon, and will be replaced to be on the safe side.

Will update after this happens and let you know how it goes. The service manager's position right now is that these are "false positives" due to some issue with the sensor or the connection to it.
 
Re: CEL - "random misfire" (recurring)

zzyzx said:
UPDATE:

The tech removed the crank sensor to do an up close inspection - they found no obvious issues with the sensor.

After putting it back in the problem no longer occurs after pretty extensive testing.

So, the only physical thing that was disrupted was the circuit from the PCM to the crank sensor. It's possible that either the connector wasn't seated well, or the sensor itself is marginal.

A new crank sensor should arrive soon, and will be replaced to be on the safe side.

Will update after this happens and let you know how it goes. The service manager's position right now is that these are "false positives" due to some issue with the sensor or the connection to it.

Do you have pics of the connector where it meets crank sensor???

Is the connector something I can get to myself to "reset", or would it need to be up on a lift and be taken apart???

Thanks!
 
Re: CEL - "random misfire" (recurring)

zzyzx said:
KBBOSS1086 - I'm certain you can reproduce the CEL. You need to drive on the highway for a good 10 minutes. Then repeatedly cruise in 4th @ 4100 RPM. My guess is that the counter needs to reach a certain value before the flashing CEL starts appearing. Once you get to the point it'll flash, getting it to flash again takes far less drive time. Also it seems to take two drive cycles of this to go from an intermittent flashing CEL to a solid CEL that stays on.

I'm going to try this as soon as I get my valve stem replaced and new tires. The CEL's still occurred as ussual. I ended up cutting a valve stem on the ride home...metal stems ordered from TireRack today.

On a positive note, I received a phone call from a manager at Ford Customre Care in response to the email that I sent Deysha on the Mustang Source Forum. The call seemed to go well and I feel for the first time that I might get some real help resolving the issue. The FCC manager is going to research the dealers in my area and reach out to one that is well versed in high performance vehicles and ask them to take on the project (this is far better than trying to find one through tiral and error). he is supposed to call me back this Monday with more information...fingers crossed.

I can't wait to get the new tires (RE-11's 285/35/19 rear and 265/35/19XL front) as well as carbotech xp-12's and xp-10's pads for 3 days at NJMP next week!
 

zzyzx

Steve
299
0
Re: CEL - "random misfire" (recurring)

UPDATE:

The Boss is home again - it was at the dealer for 2 weeks.

To sum up: Removing and replacing the original crank sensor after inspection resulted in not being able to reproduce the CEL after that point. They had already ordered and decided to replace the crank sensor to be on the safe side. The only code ever thrown in my case is a P0030. No cylinder-specific codes were ever thrown.

I didn't spend a lot of time testing today, but some preliminary testing indicated no flashing CEL. Will do more testing tomorrow.

The crank sensor is located in the bell housing on the top passenger side, and it protrudes up out of the bell housing where the connector to the PCM is located. This is what the service manager described to me, I haven't yet seen it with my own eyes.

Unfortunately, the problem has gone away without a clear definitive solution.

The connector itself wasn't loose or otherwise out of spec. The service manager was about to report back to Ford that he believed it could only be fixed with a S/W update to change the PCM parameters to not report "false positives".

He said the most helpful thing was that I was able to give them a specific set of criteria to reproduce the issue. Given this, Ford can't walk away from the problem, obviously. Especially when the criteria given are "normal" by any definition.

Knowing what I know now, here's what my resolution checklist would be:

1. Find the exact criteria that reproduce the problem (see earlier posts).

2. Detach crank sensor connector, and re-attach.

3. Remove crank sensor, and re-install. I haven't yet seen it, but it must be bolted to the bell housing and the torque specs could be way off, causing issues.

4. Re-test: try to reproduce the CEL.

5. If CEL still present, take to dealer and outline the criteria to reproduce issue.

Contact info:

Steve Thomas, 561-689-6550 x1385
Assistant Service Manager
Al Packer Ford
West Palm Beach, FL
 
Re: CEL - "random misfire" (recurring)

07SGT0547 said:
zzyzx said:
UPDATE:

The tech removed the crank sensor to do an up close inspection - they found no obvious issues with the sensor.

After putting it back in the problem no longer occurs after pretty extensive testing.

So, the only physical thing that was disrupted was the circuit from the PCM to the crank sensor. It's possible that either the connector wasn't seated well, or the sensor itself is marginal.

A new crank sensor should arrive soon, and will be replaced to be on the safe side.

Will update after this happens and let you know how it goes. The service manager's position right now is that these are "false positives" due to some issue with the sensor or the connection to it.

Do you have pics of the connector where it meets crank sensor???

Is the connector something I can get to myself to "reset", or would it need to be up on a lift and be taken apart???

Thanks!

While I can't say for sure that I've actually "fixed" anything... But after tracing the wiring harness around the engine compartment and removing & reconnecting every possible connection I could get my fingers on... It appears that I may have eliminated my CEL problems, at least for now...

Drove the BOSS about 175 miles on Wed afternoon without throwing any codes... And have taken it out on several occasions around town and on the country roads where I was able to get the CEL to flash in the past... And so far, using both keys and the same "parameters" as before, I haven't been able to replicate any P0304 codes...

And if I follow ZZYZX's resolution checklist, the only item that would be different for me is #3, since I just had a NEW Long Block installed and would assume that it already comes with a NEW Crank Sensor... Otherwise, I am like him in that "the problem has gone away without a clear definite solution"...

Hopefully, the problem will stay away and I can get back to enjoying driving the car instead of worrying about it every time I cruise around in 4th gear ???
 

zzyzx

Steve
299
0
Re: CEL - "random misfire" (recurring)

UPDATE:

So, I spent quite a lot of time today cruising @ 4k RPM and no CEL. That's great news!


07SGT0547:

Good news that the CELs have stopped!

07SGT0547 said:
And if I follow ZZYZX's resolution checklist, the only item that would be different for me is #3, since I just had a NEW Long Block installed and would assume that it already comes with a NEW Crank Sensor... Otherwise, I am like him in that "the problem has gone away without a clear definite solution"...

Well, let's think about this... The crank sensor is in the bell housing and connects directly to the PCM. I honestly wouldn't think that an engine swap would even require you to disconnect the crank sensor, and certainly wouldn't think that the crank sensor would need to be replaced with the engine (or that would be a standard procedure).

However, a record of this WILL be in the tech logs with the dealer. It would be great to know what they did - if anything - with the crank sensor and/or its connector.

In your case, I honestly think its possible the only person that disconnected/re-connected the crank sensor is you...
 
Re: CEL - "random misfire" (recurring)

know there has been a number of us with CEL issues:

I have 2100 miles and I noticed about a week ago the CEL would flash randomly with either the Silver Key or Red Key. Usually 3-6 flashes, then go out. This happened 3 X's under normal driving.

Yesterday, started out with the Silver Key; Normal drive and the CEL flashes about 10 X's then stayed on continuously (first time). I called my Service Rep at Grapevine Ford and drove immediately to the dealership so they could get diagnose the issue.

Now when the CEL came on randomly or yesterday's deal, I noticed no change in the performance of the car.

They put it on the computer and came back with Random Misfire Codes and I think something about Crankshaft???

Anyway, the problem was due to an improper install of the TracKey. The last step in the installation was not done (selling dealer in Florida; which I called and informed them). So they redid the process and problem solved.

Everything works fine and they said I should even notice improved performance. I didn't have a lot of time to drive it hard, but what little driving I did do, I thought the performance was somewhat better (could be placebo??)

Anyway, thought I would pass this information to those who might be experiencing similar issues.
 

zzyzx

Steve
299
0
Re: CEL - "random misfire" (recurring)

You might want to spend 20 minutes on the highway, spending the majority of that time cruising in 4th @ 4000-4100 RPM. That's the one condition that a few of us have been able to consistently reproduce the flashing CEL.
 
Re: CEL - "random misfire" (recurring)

Yes, did that on purpose yesterday, about a 50 mile round trip at mostly 60-75 mph.

So far, so good. I will let you know.

Thanks for input, etc.
 

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