'05 LS V6 - Sputtering & Running Rough @ Highway Speeds

[joegr]

Are new coils better built or something? Are the original ones just sh!t? Why would I need to replace them now if they seem to be fine? A read a coil is either bad or good. No need to replace it if it is working. Is this true?

The newest rev of the coil is supposed to be better. I don't know how much.

Coils are not just good or bad, that would be too easy. Unfortunately, there is a whole range between good enough and too bad. The problem is that the epoxy inside the coils breaks down over time and thermal cycles. This leads to high voltage breakdown inside the coil. Each time the coils fires, there is a little spark inside the coil. Eventually, it can get to where sometimes it only sparks inside the coil, and not at the plug. Even if it doesn't go that far, the internal spark causes electrical noise. This noise can confuse the computer into thinking that something else is wrong, like the electronic throttle system.

Some theorize that the problem might be the way the coils are mounted in the LS engine. There is no airflow over the coils, and they get hotter than the coils in many other engines.

 

[Eurythmian]

Is there a certain brand of ignition coil I need to purchase... any brand I need to avoid?
Stick with Motorcraft?
Pepboys
Autozone
Napa

Point me to the right kind and I will run out and get them today.

Thanks for clearing this up for me.

 

[joegr]

Is there a certain brand of ignition coil I need to purchase... any brand I need to avoid?
Stick with Motorcraft?
Pepboys
Autozone
Napa

Point me to the right kind and I will run out and get them today.

Thanks for clearing this up for me.

I only have experience with OEM. Max (look right) can set you up with a set at a good price.

 

[pektel]

Some theorize that the problem might be the way the coils are mounted in the LS engine. There is no airflow over the coils, and they get hotter than the coils in many other engines.

I have airflow over my coils. No covers right now.

 

[joegr]

I have airflow over my coils. No covers right now.

Over may be better than none, but you still don't have good air flow around the coils. On the 4.6L engines, the coils are out in the open, not down in a well. In any event, I haven't seen enough to prove or disprove that LS coil failures are or can be related to heat.

 

[Eurythmian]

Let's try the simple things first gentlemen. Coil problems on the v6 are less common than on a v8...but it does happen.

You say you had the problem once prior and that is why you cleaned the filter... was the problem worse after you cleaned it than before? If so I suspect the MAF sensor is dirty. Try cleaning your MAF sensor with some appropriate cleaner and see if the problem persists. Sometimes you can get too much oil on the filter and dirty up the MAF sensor.

The v6 also have problems with the pcv hose under the intake.... but that is a whole other ball of wax.

Where is the location of the MAF Sensor? And what do I use to clean it?

 

[n8bachelor]

MAF cleaner, available at any autoparts store. The sensor is located just downstream of the air intake box... inside the intake tube. It pulls out in one easy step.

 

[Eurythmian]

MAF cleaner, available at any autoparts store. The sensor is located just downstream of the air intake box... inside the intake tube. It pulls out in one easy step.

It is right after the intake box and has two star screws you remove to slide it out? Is it black plastic and silver on the other side?

I did remove what ever sensor this is and it looked clean and quite new. It's flat and about 1.5" wide and about 2.5" long. If I knew how to upload a photo to this post, I would show you what I am talking about.

Let me know if this it the MAF Sensor... I may go pick up a new one just to have piece of mind.

 

[Eurythmian]

Checked them out at O'Reilly and they want $119.00.

Mine looks clean - pretty much like I just put it on. Do you guys think it could be bad?

 

[toomanyfumes]

I had the same problem as you in my '05 V6. Started with a intermittent miss at highway speeds, soon check engine light came on. I replaced the three coils I could get at and It's ran fine since. It's too bad the dealer didn't replace the three coils under the manifold while they had it off. Bought the coils from Max (five star)

 

[Eurythmian]

The dealerships are suppose to be the group of mechanics experienced and knowledgeable of FORD product issues and how to fix them. I find it extremely alarming a few owners/enthusiasts know more about these cars then they do.

A five year old $40,000.00 car with less than 50,000 miles on the odometer should not have the issues the LS has... and the mechanics at their dealerships should know how to repair them. This is ridiculous!

I have always been a loyal FORD owner - like my father.
1969 Mercury Montego MX
1991 FORD Escort GT
1977 Lincoln Mark V Pucci Designer Series
1994 FORD Probe GT
1994 FORD Ranger Splash
1996 Mercury Mystique Sport
2000 FORD Windstar SEL Limited
1994 Lincoln Mark VIII
2005 Lincoln LS

Out of all of these cars the Mystique was a MISTAKE. One problem after another... and I'm wondering if I need to trade the LS in on something more dependable. I love this car... it's looks, it's luxury and it's power. But I need a dependable car that isn't going to cost me $500.00 a month in repairs plus the payment. There is a really nice used 2010 MKZ on the lot. I might go check it out. I've heard good things about the MKZ... and I like the new looks of the 2010.

 

[toomanyfumes]

Well you might want to think it over before you get rid of the LS right away. They have their little problems but once it's sorted out it should be a good car. In 2+ years I've changed the three coils and had the DCCV replaced.

 

[cowboyLS]

Eh, track record is still waaay better than a VW. So far so good on my 06, only had to have the DCCV replaced under the B2B warranty.
Edit : Forgot - it also has had the accessory belt pulley replaced as per the TSB (squeaks on startup in cold temps).

 

[toomanyfumes]

Ha Ha brother-in-law had a Jetta. I think maybe two doors and oppisite two windows worked. Dashboard warning lights lit up like a Christmas tree. He has a Hyundai now and thinks it's awesome compared to the VW

 

[Eurythmian]

I know three people who have owned and own Jettas... they all hate them. Always something wrong and their dealerships can never find anything wrong or know how to fix them. Windows falling out, Window Motors dying, Stalling and dash lights like it's December 25th all year long. One guy took it in for an oil change and they put the wrong oil in it. Had to replace the engine. He wanted to trade it but they wouldn't. The car was a year old and he bought it from them new. They completely destroyed his car and he is stuck with a lemon now. I will never own a VW.

 

[Eurythmian]

Bought some MAF sensor cleaner tonight. Although the sensor looked clean, there is a noticeable difference in it's performance now. Quicker pickup from a dead stop - at passing speeds it just makes me smile.

I thought I really made a big compromise with buying the V6 LS... but now after a year of driving it at really poor performance levels - and spending close to $1200.00 getting it completely tuned up, I am very happy with this car. I just hope I'm done for awhile with any surprise repairs. I know I need new brake pads and plan on doing them next month. I've got a mechanic friend who will do them for me for around $50.00 and beer.