low compression one cylinder are spark plug broke

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GON

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Had a major problem on my 2007 Ford F-350 with a 5.4L Triton engine with 90k miles. The problem is my fault as I knew of a design flaw with the spark plugs and failed to address it. The flaw is the spark plugs collapse when being removed, leaving parts in the cylinder, etc.

Last week driving from South Dakota to Pennsylvania, the check engine light came on. I kept driving but had a bad feeling, so I stopped at a AutoZone for a scan in Fargo, ND. Scan came back misfires in cylinders 3 and 4.

Got back on the road, and truck performance seemed to degrade. I stopped at a Ford dealer just across the boarder in Minnesota. They looked at the truck and tried to pull plug number 4. The technician found most of plug missing. The tech did a engine scope and stated cylinder walls are scored and top of piston has some damage on cylinder # 4. He replaced the plugs in cylinder 3,4 and 5. He next performed a relative compression test and cylinder 4 is still low. The dealership was closing so they did not have time to replace the other 5 plugs.

The dealership wished me good luck getting home. The truck drove just fine on the 1,000 mile return trip home.

Trying to identify what is the risk associated driving the truck long term with low compression in one cylinder due to a scored cylinder wall and some damage to the top of the piston.

Any thoughts?
 
Assuming the compression loss is from rings to wall sealing, or piston top cracking, the oil will get contaminated quickly by fuel and increased wear will occur, leading to premature engine failure.

Aside this, cat converter wear... bottom end wear from rocking torque, etc.
 
Well technically you already have engine failure. The cylinder damage will make it burn oil too.
 
It will start using oil and have degraded performance, if the damage gets worse and it probably will it will probably have a permanent cat destroying misfire. The top of the piston is another story, it can be anything from just an ugly ding in it to damaging it so badly it has a crack and anything in between.
Personally I would just go with a short block for $1,300 if the heads are okay (have then done at a machine shop), put new cam chains and tensioners in and call it done, its cheaper than replacing an F350. Not a very Merry Christmas but if you DIY its less than $2500.

http://www.fordparts.com/Commerce/Catalo...r%20Duty#Search
 
I went through this recently with my 5.4, It ate a washer some how.

It was cheaper to get a junkyard engine in it. Rather than replacing the piston, head, cam chains, head gaskets. Granted I didn't have degraded performance, I had a completely dead cylinder and a washer and valve floating around.

I'd get a second opinion , though. Have them check the walls closely with a camera through the spark plug hole and confirm that's really a problem. The dealer could have been trying to sell you a new engine.
 
Originally Posted By: Miller88
I went through this recently with my 5.4, It ate a washer some how.

It was cheaper to get a junkyard engine in it. Rather than replacing the piston, head, cam chains, head gaskets. Granted I didn't have degraded performance, I had a completely dead cylinder and a washer and valve floating around.

I'd get a second opinion , though. Have them check the walls closely with a camera through the spark plug hole and confirm that's really a problem. The dealer could have been trying to sell you a new engine.
Agree on the second opinion.
 
If there is internal damage, it means a rebuild one way or the other and it's your call whether you run it until it starts running bad and making noise, or stop now. The cost difference between the two (as long as something doesn't come apart inside causing catastrophic damage that would void a core refund) isn't much. If you'd be rebuilding the existing engine, stop
now and it's more likely to be saveable, but a solid salvage engine or reman is what I'd do.
 
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Coil packs will go bad on these, and the spark plugs sometimes fall apart when removing them. It is less likely that pieces of spark plug actually fell into the cylinder.Get a mechanic that will show you the actual compression numbers, hot and cold. Or do it yourself.
If #4 is toast, unplug the fuel injector and enjoy your V7 engine.
grin.gif
 
Im not a ford expert but my cousin blew the #3 on his 5.4 all the way out. From what I understand this is super common for the plugs to work loose and strip on the #3 especially around 100k. They are also known to break when removing due to design. My guess is they replaced your blown plug and gave you a worse case scenario $$$$. I would change the oil and have a good indy tech check it out in warmer weather and get the rest of the plugs changed out. Many remove the plugs hot with a impact on those and then tighten down to ~25-30ftlbs. Check ford forums and youtube(fordtechmakuloco).
 
Originally Posted By: GON
Had a major problem on my 2007 Ford F-350 with a 5.4L Triton engine with 90k miles. The problem is my fault as I knew of a design flaw with the spark plugs and failed to address it. The flaw is the spark plugs collapse when being removed, leaving parts in the cylinder, etc.

Last week driving from South Dakota to Pennsylvania, the check engine light came on. I kept driving but had a bad feeling, so I stopped at a AutoZone for a scan in Fargo, ND. Scan came back misfires in cylinders 3 and 4.

Got back on the road, and truck performance seemed to degrade. I stopped at a Ford dealer just across the boarder in Minnesota. They looked at the truck and tried to pull plug number 4. The technician found most of plug missing. The tech did a engine scope and stated cylinder walls are scored and top of piston has some damage on cylinder # 4. He replaced the plugs in cylinder 3,4 and 5. He next performed a relative compression test and cylinder 4 is still low. The dealership was closing so they did not have time to replace the other 5 plugs.

The dealership wished me good luck getting home. The truck drove just fine on the 1,000 mile return trip home.

Trying to identify what is the risk associated driving the truck long term with low compression in one cylinder due to a scored cylinder wall and some damage to the top of the piston.

Any thoughts?


Did they do a leakdown test to make sure the exhaust valve wasn't the issue? Chunks of spark plug trying to get through an exhaust valve can do alot of damage on those.
 
A cylinder balance test (cylinder drop test) will tell the TRUE story.

NOT All cylinder walls with a little scoring have bad compression.
 
Had two blow out on me while driving, limped it home sounding like a thrashing machine. Helicoiled two plugs in and drove it another 10K or so no issues.

I sold that truck and the guy still drives it i see it often.


I would keep an eye on consumption to see if the cylinder is really scored..also do a smoke test with a white rag at the tail pipe.. if its burning oil you will see it on the rag. I know not as scientific as a boroscope but it has kept me from buying a few oil burners over the years.
 
Horror stories like this keep me putting new pieces and parts into the Rat. You got the truck home. Thats the main thing. Please post the continuing saga of your F 350.
 
Let's not get two issues confused. The older 5.4s eject spark plugs due to a lack of threads, and the 3V has spark plugs that break into pieces on removal because they're poorly constructed and dug in there like the knife Ford stuck in the backs of all 5.4 3V owners.

I went through this, gently using an impact gun to get them out.
 
Thanks for all the great replies!!

Although I do most of my own maintenance, on this case I am returning to the local dealer after watching the challenges of spark plug removal on the 5.4 triton. Have a appointment at the local Ford dealer for the second Tuesday in January, that is the soonest they can get me in.

I will request the dealer recheck cylinder 4. Also, the servicing dealer mentioned heliocoil, they may have used one or more on the three plugs they replaced.

My big question- can I utilize this truck under load for another 25k miles if I watch for oil consumption? Looks like fuel may go unused from cylinder 4 (if I am reading the replies properly) and cause catalytic convertor failure))?
 
Did they do a leakdown test to make sure the exhaust valve wasn't the issue? Chunks of spark plug trying to get through an exhaust valve can do alot of damage on those. [/quote]

I agree with the valve issue. I would think the damage would mostly be valves, a beaten up piston and maybe cylinder head damage.
 
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Well, it already has low compression (verified by leak down test), so it's damaged. Unless if the piston is cracked though it'll likely keep plugging along until something else goes.

I used to worry about cats dying prematurely from oil usage, but Saturns (and some Corollas) drink oil like there's no tomorrow and seem to be fine, so I'm not sure I'd worry greatly about that--as long as the cylinder fires it'll probably burn it enough.

I'd get the remaining plugs changed and motor on, unless if a) you have money to throw at this, or b) you can feel the loss of power when under load.
 
Sure you can probably get another 50K or more out if it as long as there is some compression eg 60 psi, that will at least should be enough to keep the cylinder firing and clear of excess fuel. It wont be that noticeable as the offending cylinder is contributing something and not just a dead hole.

The helicoil bit is troubling me, older 5.4 has plug blow out issues and some people used helicoils but not a dealer, they used the OE approved time-sert method with an aluminum insert. Yours did not have this issue, the plugs broke upon removal not driving down the road AFAIK.
When they broke a special removal tool is used and the plug remnants can be be removed without dropping anything into the cylinder.
This just doesn't smell right. If you have a garage get it in there and pull that plug, see if it in fact has a helicoil then use a cheap boroscope to look at the piston and cylinder walls, unless you have a mechanic you know and trust you cant trust anybody.

The more I think about this if a piece large enough to damage the piston came loose the chances of valve damage are almost certain running the engine. Its more than possible there is nothing wrong with this engine at all, just a bad COP or plug and they were hoping to hose a traveler a long way from home.

Do your own compression test, from the sounds of it you cant trust their diagnosis 100%.

cheap USB boroscope
 
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Originally Posted By: GON
Also, the servicing dealer mentioned heliocoil, they may have used one or more on the three plugs they replaced.


Do you remember what the servicing dealer charged for their work? What does it say on the invoice as far as work performed? Thank you.
 
Originally Posted By: SatinSilver
Originally Posted By: GON
Also, the servicing dealer mentioned heliocoil, they may have used one or more on the three plugs they replaced.


Do you remember what the servicing dealer charged for their work? What does it say on the invoice as far as work performed? Thank you.


I paid about $450 once shop supplies and other misc charges. It should be noted I arrived mid afternoon, and they looked at my truck as the shop was closing. They were not willing to replace the remaining five factory installed plugs as it was closing time. They did not seem to have options to upsell me as I was a traveling customer (I am a resident of Alaska and was heading to Pennsylvania).

Sure wish I could have some way to know the likeliness of the truck making five round trips from Pennsylvania to Utah. The truck is going to a Ford dealer in Pennsylvania the second Tuesday in January for the remaining five plugs to be replaced. Wonder if they can take a second look at the low compression on cylinder 4?

Attached is the invoice from Ford. Tried to upload the image but it is not displaying.

Here is a cut and paste of the invoice:
Installed PZH 14F :SPARK PLUG

3 (cy1 7 . 4 2

242.(


Installed 3L3Z 12029 BA :COIL ASY - IGNITION

183.64

VVERIFIED COMPLAINT. MISFIRE CODES FOR CYLINDERS
3,4,&5. PERFORMED POWER BALANCE. #4 LOW ON POWER.

PERFORMED RELATIVE COMPRESSION. #4 15%LOW ON
COMPRESSION. REMOVED ACL, AND REMOVED #4 COP
AND SPARK PLUG. FOUND MOST OF SPARK PLUG TO BE
MISSING. USED SCOPE. CYLINDER WALLS ARE SCORED AND
TOP OF PISTON HAS SOME DAMAGE. CUSTOMER SAID
TO PUT NEW PLUG AND COIL IN #4 AND NEW PLUGS IN
#3&5. REPLACED #3&5 SPARK PLUGS. REINSTALLED ACL.
STARTED VEHICLE. VEHICLE RUNS GOOD. PERFORMED
RELATIVE COMPRESSION #4 IS STILL LOW. CLEARED
CODES. COMPLETE.
Sub Total: 377.90
 
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