Misfire problem please help!

Gagurass

Gagurass

LVC Member
Joined
Jun 24, 2018
Messages
20
Reaction score
1
Location
New jersey
Hi everyone new to the forums.

I bought a 2005 Lincoln LS V8 with 136,000 miles and the second I got on the highway the check engine came on. Mechanic said 1,4,7 were misfiring so I had my former mechanic friend change all of the coils and spark plugs. We used NGK iridium plugs and coils from parts galaxy which had good reviews on amazon. The wiring for the spark plugs looked bad and my friend warned me that could be the problem, but there was no oil in any of the wells, just looked like previous owner had only done one side of the spark plugs and left the other untouched. The car ran like a dream, but fast forward a couple hundred miles, im leavinng work and upon starting the car on a hot day the check engine is flashing and the car is obviously misfiring. Check engine settles at cruising speed but flashes at low rpm. Autozone reader said cylinder one misfire. I am really at a loss of how this could happen so soon. Any help would be appreciated as I do like these cars.
 
Coils -> Motorcraft. (Have to change the plugs again too, make sure the gap is 1.0mm.) Hope that you haven't damaged the PCM with those coils.
 
joegr said:
Coils -> Motorcraft. (Have to change the plugs again too, make sure the gap is 1.0mm.) Hope that you haven't damaged the PCM with those coils.
Click to expand...
Somehow I don’t think this will be a permanent fix...going to fix the misfire and sell thanks for your help.
 
Gagurass said:
Somehow I don’t think this will be a permanent fix...going to fix the misfire and sell thanks for your help.
Click to expand...

Do be aware that there are several of us with LSes that don't misfire. I'm just over 200K miles on my 04 and just under 200K miles on my 06. Both are at or over 100K miles on the COPs.
 
joegr said:
Do be aware that there are several of us with LSes that don't misfire. I'm just over 200K miles on my 04 and just under 200K miles on my 06. Both are at or over 100K miles on the COPs.
Click to expand...
I understand but I trust amazon reviews and the parts have a warranty I have contacted parts galaxy about. I am worried something else is causing the coils to go bad and shelling out $400 on coils of similar design from motorcraft will not fix the issue.
 
Motorcraft fixed the problem with the epoxy they were using. Most of the aftermarket suppliers have not.
Suit yourself. You asked for advice, but you don't have to take it.
 
joegr said:
Motorcraft fixed the problem with the epoxy they were using. Most of the aftermarket suppliers have not.
Suit yourself. You asked for advice, but you don't have to take it.
Click to expand...
I will drive the car until I can order the motorcraft coils. Do you reccomend any sparkplug brand or will any 1mm do? Also some of the coil cover bolts are missing. What exactly are those called/what size so I can order a pack? Again thanks for your help sorry I am a bit of a noob with these cars but I like the power so I will give it a shot.
 
Gagurass, let me tell you this.

Joe knows more than just about anyone I've ever seen, to include Ford Certified Technicians about these cars.

There are a lot of cars that do better with aftermarket parts, but the LS is quirky enough in itself where Motorcraft is the one go-to for most things.

Things that make sense on most other cars, don't on this one. Overall he gave you great advice. If the car's not for you then sell it, but make sure you find a forum and do research on the next car you buy so you don't find yourself in the same situation.
 
The plugs should be NGK 7090 BKR5EGP or better.
The gap on each plug must be correctly set to 1.0mm. (They claim to be preset, but a few always have to be corrected. This must be done carefully or the plug will be damaged.)

You must also verify that no water is getting into the plug wells. Any rust on the plugs indicates that water is getting in. There is a seal around the wiper shaft one the cowl that rots out.

The bolts should be -W500202-S309, any 12mm (or so) M5 should do. You may find the the real problem is that the inserts in the valve cover are loose or gone.
 
joegr said:
Do be aware that there are several of us with LSes that don't misfire. I'm just over 200K miles on my 04 and just under 200K miles on my 06. Both are at or over 100K miles on the COPs.
Click to expand...

125k + on high quality aftermarket coils.

Motorcraft or good aftermarket are going to cost around $50 each. Worth the $$$ considering the headaches that the cheap ones cause.
 
joegr said:
Coils -> Motorcraft. (Have to change the plugs again too, make sure the gap is 1.0mm.) Hope that you haven't damaged the PCM with those coils.
Click to expand...
is there a part number on these motorcraft coils? Because I'm finding 8 for 120$ then 8 for 430$
both motorcraft brand
 
GEOFFwithaLS said:
is there a part number on these motorcraft coils? Because I'm finding 8 for 120$ then 8 for 430$
both motorcraft brand
Click to expand...

Yes, but it doesn't matter. People sell aftermarket with the Ford part number. You have to use a reliable source. I've rarely seen them for less than $50 each ($400 total), but I have heard of some finding them at $40 each once in a while.
The $430 is probably real, the $120 is certainly fake.
 
joegr said:
Yes, but it doesn't matter. People sell aftermarket with the Ford part number. You have to use a reliable source. I've rarely seen them for less than $50 each ($400 total), but I have heard of some finding them at $40 each once in a while.
The $430 is probably real, the $120 is certainly fake.
Click to expand...
 
ok thanks. I'm replacing all plugs and coils as well as cats. going with eastern. Do you have any suggestions on anything I should replace with them?
 
Gagurass said:
Hi everyone new to the forums.

I bought a 2005 Lincoln LS V8 with 136,000 miles and the second I got on the highway the check engine came on. Mechanic said 1,4,7 were misfiring so I had my former mechanic friend change all of the coils and spark plugs. We used NGK iridium plugs and coils from parts galaxy which had good reviews on amazon. The wiring for the spark plugs looked bad and my friend warned me that could be the problem, but there was no oil in any of the wells, just looked like previous owner had only done one side of the spark plugs and left the other untouched. The car ran like a dream, but fast forward a couple hundred miles, im leavinng work and upon starting the car on a hot day the check engine is flashing and the car is obviously misfiring. Check engine settles at cruising speed but flashes at low rpm. Autozone reader said cylinder one misfire. I am really at a loss of how this could happen so soon. Any help would be appreciated as I do like these cars.
Click to expand...


Hello - I am no mechanic by any means but I can share my nightmare with my 03 LS/misfire nightmare/check engine light that never went out for two years......I had (well still have the car sitting in my driveway as I don't have the heart to scrap it out) an 2003 Lincoln LS V8 w/premium package and if it was me I'd get rid of that car now. If it's already giving you problems at 125,000 miles your gonna be in for a long expensive, frustrating ride with that car and the more/higher the miles those cars have the worse the issues get trust me. As like other Ford cars (at least that I've owned) the misfiring/check engine light issue can be/is a NIGHTMARE. When I was driving my LS no joke I literally replaced at least 6 of the 8 coils some twice and that s**t is NOT cheap. Used the best spark plugs too (not sure if that matters as I am not a mechanic). Matter a fact when I "parked" my LS at 205,000 miles I still had misfiring issues/check charging system/flashing check engine light after replacing $200-$220 alternator and a $120 battery. Finally parked car as frame or A arm in rear was hanging on by a thread/i.e rotted out is what mechanic told me and that it would not pass inspection (I live in wonderful (NOT) New England and the salt/and or brine used on snowy/icey roads ruins our cars up here in no time....it sucks!!). Don't get me wrong when I first bought the LS (used with 98,000 miles on it) I loved it, it's black on black (with premium pkg. or whatever it's called) and was such a sharp looking car and fast too....but when things started to go wrong they really went wrong and never got better just worse and more expensive.
 
jchurchill@bondoptics.com said:
Hello - I am no mechanic by any means but I can share my nightmare with my 03 LS/misfire nightmare/check engine light that never went out for two years......I had (well still have the car sitting in my driveway as I don't have the heart to scrap it out) an 2003 Lincoln LS V8 w/premium package and if it was me I'd get rid of that car now. If it's already giving you problems at 125,000 miles your gonna be in for a long expensive, frustrating ride with that car and the more/higher the miles those cars have the worse the issues get trust me. As like other Ford cars (at least that I've owned) the misfiring/check engine light issue can be/is a NIGHTMARE. When I was driving my LS no joke I literally replaced at least 6 of the 8 coils some twice and that s**t is NOT cheap. Used the best spark plugs too (not sure if that matters as I am not a mechanic). Matter a fact when I "parked" my LS at 205,000 miles I still had misfiring issues/check charging system/flashing check engine light after replacing $200-$220 alternator and a $120 battery. Finally parked car as frame or A arm in rear was hanging on by a thread/i.e rotted out is what mechanic told me and that it would not pass inspection (I live in wonderful (NOT) New England and the salt/and or brine used on snowy/icey roads ruins our cars up here in no time....it sucks!!). Don't get me wrong when I first bought the LS (used with 98,000 miles on it) I loved it, it's black on black (with premium pkg. or whatever it's called) and was such a sharp looking car and fast too....but when things started to go wrong they really went wrong and never got better just worse and more expensive.
Click to expand...
Oh and btw. mine had oil leaking into where coils go.
 
jchurchill@bondoptics.com said:
Hello - I am no mechanic by any means but I can share my nightmare with my 03 LS/misfire nightmare/check engine light that never went out for two years......I had (well still have the car sitting in my driveway as I don't have the heart to scrap it out) an 2003 Lincoln LS V8 w/premium package and if it was me I'd get rid of that car now. If it's already giving you problems at 125,000 miles your gonna be in for a long expensive, frustrating ride with that car and the more/higher the miles those cars have the worse the issues get trust me. As like other Ford cars (at least that I've owned) the misfiring/check engine light issue can be/is a NIGHTMARE. When I was driving my LS no joke I literally replaced at least 6 of the 8 coils some twice and that s**t is NOT cheap. Used the best spark plugs too (not sure if that matters as I am not a mechanic). Matter a fact when I "parked" my LS at 205,000 miles I still had misfiring issues/check charging system/flashing check engine light after replacing $200-$220 alternator and a $120 battery. Finally parked car as frame or A arm in rear was hanging on by a thread/i.e rotted out is what mechanic told me and that it would not pass inspection (I live in wonderful (NOT) New England and the salt/and or brine used on snowy/icey roads ruins our cars up here in no time....it sucks!!). Don't get me wrong when I first bought the LS (used with 98,000 miles on it) I loved it, it's black on black (with premium pkg. or whatever it's called) and was such a sharp looking car and fast too....but when things started to go wrong they really went wrong and never got better just worse and more expensive. Good luck to you.
Click to expand...
 
Yeah, and you'll never get anywhere if you don't:
Replace all the coils at once, use real Motorcraft, >$50 each
Replace all the spark plugs at exactly the same time as the coils.
Verify/set all the spark plug gaps to exactly 1.0mm
Replace any leaking valve covers first.
Verify/replace the passenger side wiper cowl seal first.

Fool around with it and let it misfire for days, and you will damage the PCM and never get rid of the misfires whatever else you do.

I have two LSes. One is just short of 200K miles, and the other is over 200K miles. I do not have any misfires on either. In both cases, I did the above immediately when marginal misfires started (before the light came on). I am at about and over 100K miles on the current set of coils on both.

The point here is that your experiences do not apply to everyone.
 
My LS has been running like a dream since I did the coils a second time with the expensive coils. Only issue is the car computer telling me I get a combined 13.3 mpg which adds up to about $60 in premium fuel during a week of driving...rough for a college student but car is a rocket. Considering a cold air intake and a tune down the road.
 
GEOFFwithaLS said:
thanks Joe, do you have any experience with these guys?
Click to expand...

No, no personal experience with them. There are others on this board that have. I think that so far all but one had a positive experience with them.
 
You must log in or register to reply here.

Members online

No members online now.
Total: 180 (members: 0, guests: 180)
Back
Top