2000 3.9L Misfires

K

Keith

Registered
First of all, I just want to say that I recently joined this forum tonight and have been amazed with the friendly assistance that is being shared here!

I have a small problem that has been going on for a while....

First off, about the car:
It is a 2000 3.9L V8 with a little less than 50,000 miles on it.

About a year ago I noticed shaking in the car as I idled as well as when I accelerated at slower incrimants. (Forgive my typos please, its been a long day!) It did this for about 4 months (Maybe 1000 miles). Finally one day it threw the MIL indicator on. I took it to the shop and they said there was a misfire in cylinder #7. We replaced the coil as well as the plug. The guy at the shop wanted me to replace every coil and plug which was going to cost about around $1200 or so.

Well a few months later and the car begins to shake a little just like the first situation. It hadnt thrown the MIL light on or anything so I was just going to wait for that. About 4 weeks ago I went on a road trip, made it about 225 miles from home and the car MIL light started flashing. The car started to shake violently. I tow it to a place where I could check it out and it pulled 2 codes for a misfire. Cylinder #2 and #4. I ordered the parts and bunked with an old friend until they arrived the next day.

As I am in the advanced auto parking lot, I take off the plastic cover (which is a real pain!!) and I find the ignition coil on cylinder #2 to be pretty much out of the hole completely! It had a slit down the side of it and the spring that contacts the plug was sitcking out the side. The impact of whatever caused the ignition coil to seperate from the grommet that holds it to the block. I check and find that the plug is no longer in the block at all. The threads were OK but the pole on the plug was completely bent in.

I bought 2 coils and 2 plugs to replace these 2 cylinders. The codes disappear and I am good to go.

Now that I am home, it is starting to do this shaking again. I bought all new coils for the remaining 5 cylinders that have not been replaced. I havent gotten free time to replace #5-8 yet.

After this long explanation, and I appologize for that, I have 2 questions:

1. Should the coils be going bad this early in to the engine's lifecycle?

2. Is there a way to hook up a diagnostic scanner to find out the exact coil that is misfiring? I bought a product from AutoTap today with the enhanced ford codes but it does not give me a parameter for "Misfire Cylinder #<blah> Counter" like it does for other cars. Is this not a sensor that can be monitored?

Any help you can give me, I would greatly appreciate it!

Once again, sorry for the length of this post!!
 
RE: 2000 3.9L Misfires

I’m having a problem that sounds like yours. Although the wife’s car is not throwing codes. It shutters slightly at light acceleration – just like there is a miss-fire. I did the 100K mile tune up, replacing the fuel filter, air breather and plugs. I installed platinum plugs. The wife is now saying that the shutter is better, but still there. I confirmed she is correct about the shutter being still around.

It looks like the coils are all the same. I’m going to buy a new coil. Each week I’m going to swap out an old coil with a new one. If I find a swap that removes the shutter, I’ve nailed it. If I find improvement, I’ll leave it and buy another new coil. And then start the swap game on the next coil.

If I’m lucky, there is only one bad coil. At the worst case, I’ll replace them all….
 
RE: 2000 3.9L Misfires

Im curious to see if when you replace this, the misfire goes away temporarily and then comes back. From what I understand the coils are a wear and tear item. A mechanic told me that ford recommends replacing all the coils at the same time. I have not confirmed either way unfortunately. All I know is that I've replaced 5 now and there is still a misfire...

The shuddering is getting worse the past couple days. I do not think the car is happy.

I wish I could minitor the misfires to see whats going on!

Good luck!

BTW, Ford has coils for $100 ea. I went to advanced auto and got them for $50. I am not sure if there are any quality differences or what not.
 
RE: 2000 3.9L Misfires

Well I bought and replaced the first one today. The wife will tell me if the shutter is any better on that plug replacement.

The coil listed in O’Reilly’s computer was wrong. The correct BORG/WARNER number for a 4.6L coil is E223. It cost 40 bucks and has a forever warranty!

I suggest you see if they have a coil for car. ‘Cause if your coils go bad after awhile, you could get FREE replacements for the life of your car!

I’m gonna use them in the wife’s car (The Mark is too old to use them. But I do run forever spark plug cables. I’m on my Second FREE set now!)
 
RE: 2000 3.9L Misfires

Kieth, if I understand your post correctly (the reference to the rubber boot cracked and the spring hanging out the side), there's some money to be saved here.

Sure, Ford has coils for $100, but it's often not the coils that go bad; it's the rubber plug boots on them, which are removable and are available from Ford for ~$12.00.

Is this a common problem? Unfortunately, yes.

There are two reasons this happens on 3.9 LSs.

1. The "O" rings on the rocker covers around the spark plug wells deteriorate and allow engine oil into the wells. This swells the plug/coil boots, and since oil is a great conductor, a new liquid path to ground is created.
Was there any sign of oil in your wells?
Replace the coil boot and plug as a short term repair, but the valve cover gaskets need to be replaced. It's not an easy job; Ford Warranty Ops pays us 6.5 hrs, and it takes that long to do!

2. Water entry. Was there any sign of rust or water corrosion on your plugs or boots?
Water drips through the cowl area and wicks its way along the coil wiring harness into the spark plug wells. Once it's in there, it's trapped. It cannot evaporate out.
Ford has issued a TSB, 05-16-02, for '00-'05 LSs. It provides a part number for new coil covers with improved sealing.
# XW4Z-12025-AD

Can a misfire be monitored? Of course it can!!! There's ~1200 signals flowing through the DataStream at any given time in your LS. They're all accessable through the DLC (Data Link Connection) under your dash.

I want you and anyone else reading this to throw your BS "Codereaders" into the garbage!!!

Anything, and I mean anything, you need to do or see is done though PCs. I use a Panasonic Toughbook loaded with Ford's IDS (Integrated Diagnostic System). You can't get that, because it's proprietary, but there's a lot of substitutes out there.

I've never used it myself, but I have friends with independent shops who swear by this:
www.obddiagnostics.com
These guys give you the software free when you buy whatever USB to DLC adapter cables you need. You can go for swim in the DataStream rather than just dipping your toe for ~ $85.00.
There's a couple of drawbacks to this software. It comes with no training programs, so you need to already fully understand OBDII to interpret what you see. It also only shows you PCM related signals, when you actually have EVERY signal in the car, from ABS to EATC to seat memory etc, etc, available at the DLC.

www.troublecodes.net/technical/scaninfo.shtml
is an independent site that lists, links, and reviews OBDII diagnostic software and equipment.

I've never seen it in action, but AutoTap software looks good. It appears to be able to talk to all modules and comes with training programs and "known good" signal tables.

To get an idea of what's flowing through your car's Multiplex Network, click on
www.autotap.com/product_family.asp?FamilyId=260
and click the Available Parameters hyperlink.
Yes, all those data parameters (and more) are flowing through your car's Network, and you can see them any time you want with the right programs!!
 
RE: 2000 3.9L Misfires

Frankie,

This is GREAT information! You spoil us. We are really fortunate to have your expertise on LOD !

To the powers of this board that can put this info into the "Tech Pages" ought to consider doing so. This would help the whole LOD family.

Bud Pytko
'97 LSC Silver Frost
'05 F250 SD CC PSD 4 X 4 AZ Beige
'94 Prowler 5th Wheel
http://squarebirds.org/images/BudPytko97LSC.jpg
 
RE: 2000 3.9L Misfires

Bud, it makes me frustrated sometimes when I see posts by LOD members who have problems and don't try any diagnostics because they simply have NO CONCEPT of how complex and intelligent OBDII systems are.

" My check engine light's on. What do you guys think it is?"

Keith is on the right track and asking for the most important thing he needs: knowledge.

I want to provide it. In particular, I want to teach everyone to respect the complexity of their cars. I want Keith and others to understand the wonderful, Science Fiction nature of OBDII. There's 16, yes, sixteen, control modules/processors in his LS, and through OBDII they're multiplexed together and sharing enough information and actuation to function as a single electronic entity.

All OBDII systems work like this.

We're not driving cars. We're riding in friggin' Borg cubes!!

Understanding this alone is worth more than any tool you could buy.
 
RE: 2000 3.9L Misfires

Us 'old guys' remember too well about our back-yard wrenching. We had just about enough knowledge about automobiles to be dangerous. If we didn't understand what was wrong we could simply 'throw parts at the car' and be danged, that probably worked more than it didn't. Those were simpler days and now with the computerization of everything electric and mechanical/electric - Those days are gone - FOREVER. Now it's time to advance and learn or quit working on your own car. If you can't learn, I hope you have a great paying job!

Guys (and gals) we have a guy here that wants to help us understand - and best of all, he's doing it at no cost to us!! WOW -I'm ready to listen and I believe an 'old dog' CAN learn new tricks.

Thanks again, Frankie. Keep on teachin'

Bud Pytko
'97 LSC Silver Frost
'05 F250 SD CC PSD 4 X 4 AZ Beige
'94 Prowler 5th Wheel
http://squarebirds.org/images/BudPytko97LSC.jpg
 
RE: 2000 3.9L Misfires

OBD-II? Multiplexing? Shoot, this old driller is still trying to learn EEC-IV. :+
 
RE: 2000 3.9L Misfires

Frankie, Thanks for your reply!

With the Autotap scanner that I have, it goes through a sequence when it first links up with my laptop. It scans for "Available peramiters" out of the ones it supports. Out of all the peramiters, it detects around 263 available peramiters that it can monitor.

Do you have any experience with the auto tap hardware/software?

It has a reading for total cumulitive misfires, "low word" misfires, total cylinder events..but nothing per cylinder. The only thing it monitors per cylinder is infector fauls where it says open or closed.

Can you explain to me the difference between a "low word" and a cumulitive misfire? Also, I get a lot of "cylinder events"...is this event simply every sime a cylinder fires or is it an issue?

I opted against the regular code reader and did go with the PC software so I could log the data from my car during a driving scenario. I can see it being very handy if it can log the misfires per cylinder. Perhaps if this is a peramiter that I should be able to read, I will call auto tap and find out why I cannot.

Regards,
Keith
 
RE: 2000 3.9L Misfires

Wow, Keith! Here I am getting all didactic and preaching about "knowledge" and you're already way ahead of me.
Welcome to LOD!
I'm pleased to meet you!

Here's Ford's textbook expanation of the Misfire Monitor:

"MISFIRE DETECTION MONITOR
The Misfire Detection Monitor is an on-board strategy designed to monitor engine misfire and identify the specific cylinder in which the misfire has occurred. Misfire is defined as lack of combustion in a cylinder due to absence of spark, poor fuel metering, poor compression, or any other cause. The Misfire Detection Monitor will be enabled only when certain base engine conditions are first satisfied. Input from the ECT or CHT, MAF and CKP sensors is required to enable the monitor. The Misfire Detection Monitor is also performed during on demand self-test.

The PCM synchronized ignition spark is based on information received from the CKP sensor. The CKP signal generated is also the main input used in determining cylinder misfire.
The input signal generated by the CKP sensor is derived by sensing the passage of teeth from the crankshaft position wheel mounted on the end of the crankshaft.
The input signal to the PCM is then used to calculate the time between CKP edges and also crankshaft rotational velocity and acceleration. By comparing the accelerations of each cylinder event, the power loss of each cylinder is determined. When the power loss of a particular cylinder is sufficiently less than a calibrated value and other criteria is met, then the suspect cylinder is determined to have misfired.
Misfire type A:

Upon detection of a Misfire type A (200 revolutions) which would cause catalyst damage, the MIL will blink once per second during the actual misfire, and a DTC will be stored.

Misfire type B:

Upon detection of a Misfire type B (1000 revolutions) which will exceed the emissions threshold or cause a vehicle to fail an inspection and maintenance tailpipe emissions test, the MIL will illuminate and a DTC will be stored.

The DTC associated with multiple cylinder misfire for a Type A or Type B misfire is DTC P0300.

The DTCs associated with an individual cylinder misfire for a Type A or Type B misfire are DTCs P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0309 and P0310."

As you can see, the PCM is counting and logging.

A "Low Word" misfire is below the 200 misfire threshold. I use this if there's no MIL (Malfunction Indicator Lamp- the Ford term for Check Engine) flash or DTC and the customer is experiencing "fishbites" or rare single miss jerks. Anything other than zero is worth investigating.

No, I can't see misfires in realtime while driving with Ford's IDS either. What I do is reset KAM so the misfire monitor counts are cleared back to zeros, go for a drive until I feel the miss, then do a KOEO self test for pending P030x codes and go into Mode 6 memory to view the misfire monitors. Again, any individual cylinders with counts other than zero may need checking.
Use your own discretion; if you're looking for a dead miss, you'll obviously be more interested in the cylinder with 50,000 cumulative misses than the one with 3!

My only knowledge of Autotap is what I've seen in the 'web, but surely since the car's PCM identifies misfires by cylinder number, doesn't the Autotap software pass that information on to you?

Another thing: yes, coil boots fail much more often than coil bodies, but coil failures on LSs are much more common than they should be.

What spark plugs are you using? I have no explanation to give you, just experiences, but Ford COP ignition systems and NGK or Bosch plugs just don't mix.
Recently, I had a customer call me a liar to my face because he'd just done an NGK tune-up 2200kms prior and I called 3 misfiring plugs. My service advisor finally settled him down with a challange: if we did a Motorcraft tune-up and the misses were still there, he'd get it for free!
The misses went away. He paid.
 
RE: 2000 3.9L Misfires

Frankie,
Thank you for the welcome and the explanations.

I do have a peramiter that I can monitor for the Misfire monitor. It always says Complete but another peramitor is "Misfire monitor during this OBDII drive cycle" and it always says no. I am assuming that the Misfire Monitor is just part of the emissions monitors that initiates after the drive drive cycle and after emissions tests are cleared when the DTC and/or MIL is cleared.

I will admit to you that I am not the most knowledgable when it comes to cars! I am hoping to understand this car much better but until I learn the terminology and what I am missing, I am screwed. The AutoTAP does have the peramiters to monitor Cylinders in their software per cylinder, however it does not detect that the car has the peramiter to monitor.

It is interesting what you mention about the Bosch plugs. I will go out and buy a set of motorocraft plugs since i currently have 8 cylinders all running bosch double platinum plugs.

Since i have bought 8 new coils, I will just throw them in for good measure and get this all out of the way. I have been fighting misfires for over a year now and I just want them outta here!

:)

Regards,
Keith
 
RE: 2000 3.9L Misfires

Hoo, boy!

Trust me on this: Bosch=Bad!!! This might be your root cause.

Didn't your Autotap come with any training and support? The website advertises a "Guide to OBDII" sub-program that appears to be pretty extensive. There's also a few "Diagnosing Misfires" articles on their www.autotap.com/technical_library.asp page.

Of all the data parameters passing in and out of the PCM, they seem to be giving you access to the least informative. Are we both misunderstanding something?

Back to my first post to you: was there any sign of oil or water entry in the wells? Be sure to address this if needed.

The revised coil covers are worth the $60.00, and be sure to use silicone di-electric paste in the new coil boots to keep them watertight.
 
RE: 2000 3.9L Misfires

There was a ton of oil in the wells..especially the ones that were misfiring. I thought this was normal though. See I told you I was not a master at cars. I am a computer guy!

How would one prevent this? is it possible that this has caused misfires?
 
RE: 2000 3.9L Misfires

[div class="dcquote"][strong]Quote[/strong]
There was a ton of oil in the wells..especially the ones that were misfiring. I thought this was normal though. See I told you I was not a master at cars. I am a computer guy!How would one prevent this? is it possible that this has caused misfires?
[/div]

Absolutely can cause misfires.

If like the Mark VIII motor, the cam covers need re-sealed to prevent oil seepage into the spark plug wells. Also double check the PCV valve and system for proper operation.
 
RE: 2000 3.9L Misfires

Can anyone tell me the OEM plug that is on the LS V8? Is it motorcraft brand? I assume they are also Platinum from what I have read.

Regards,
Keith
 
RE: 2000 3.9L Misfires

What was the first thing I wrote in my first post?

"Is this a common problem? Unfortunately, yes.

There are two reasons this happens on 3.9 LSs.

1. The "O" rings on the rocker covers around the spark plug wells deteriorate and allow engine oil into the wells. This swells the plug/coil boots, and since oil is a great conductor, a new liquid path to ground is created.
Was there any sign of oil in your wells?
Replace the coil boot and plug as a short term repair, but the valve cover gaskets need to be replaced. It's not an easy job; Ford Warranty Ops pays us 6.5 hrs, and it takes that long to do!"

Replacing the valve covers (correctly referred to as camshaft covers) isn't an fun job on LSs. The passenger side isn't bad, but the driver's side is a PITA! If you're going to attempt it yourself, take the windshield wiper cowl and crossbrace off; this opens everything up a lot. There's so many steps with hoses and connectors to undo, and brackets to move, trying to give you complete instructions might be futile.

If you have enough confidence, go for it. Be methodical and use common sense. If you don't want to do it yourself, please don't take it to Bubba's Kwikyfix. Go to a dealership or someone with Lincoln experience.

For now, go ahead and replace the plugs and coils anyway. You don't want to have this car misfire long enough to begin damaging the catalytic convertors.

The correct spark plugs are:
Motorcraft #AGSP32F.
They're double platinum.
Ford Parts Division has switched to a new catalogue system which will package these same plugs as:
#SP 467.
You can get them from any Ford parts department by either number.

When you do this, you won't have to clean the oil from the wells. As soon as the plugs come out of their holes, the oil will go down into the cylinders like flushing a toilet.

THIS PRESENTS TWO PROBLEMS.

1. I've never seen this, but I've heard stories and it's very possible: If a lot of oil goes into the combustion area, you slam the new plugs in, and crank the engine, you may risk hydraulically locking the engine. Bad, bad, bad!
Take all of the plugs out, go have a beer, and give that oil ~20 minutes to leak past the oil rings before putting the new plugs in and firing the motor up.

2. There will still be oil sitting on top of the pistons, and when you fire up, the car will smoke for about a minute. I MEAN smoke; it'll look like James Bond's Aston Martin evading pursuit. This isn't a problem. It burns off quickly, but the amount produced takes a lot of people by suprise.

One last thing, Keith: The amount of oil in your plug wells does not give you a true indication of the severity of your leaks. Is it the accumulation of 3 years of minor leaking, or is it 3 weeks' worth of nasty leaks?

Do the plugs and coils now, keep track of any oil returning, and you might be able to postpone the cam cover repair for a while.
 
RE: 2000 3.9L Misfires

Frankie,
As always, thanks for your reply. Initially, when I had my first misfire, I vaguely recall there not being any oil in the wells. When I was removing plugs for a complete plug change, I noticed some of the plugs had oil on the tips. It is very possible that the oil that I am seeing in the wells right now is from the spark plug that made its way out of the hole. Actually I am pretty sure that is the case.


I have another curious question. What is the easiest way to get the plastic cover off of the area in which the plugs are??? I find it very odd that ford would have designed that engine without being able to service the plugs easily!

I am currently using a 7mm wrench to get to them...then I had to improvise a little and get a 7mm socket with a universal socket adapter attached to act as a small handle to where I can turn it by hand. If not, i'd be there for an hour removing 1 screw!

Any tips or tricks you can teach me in this case?

Thanks again for everything!

Regards,
Keith
 
RE: 2000 3.9L Misfires

I use a 1/4" drive 7mm flex socket from Snap-On and put it on a 12" long 1/4" drive extension. I bought the flex socket specifically for LSs; I'm sure you've noticed already that even a 1/4" drive shallow socket on a universal is too long for the bolt by the brake booster.

Another example of, "What the &*$# were they thinking?!?"
 
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