Bad roller follower causing misfires?

Ethos395

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Got a 05 gt with 160k that keeps misfiring made a post about a while back but its returned. Started doing more research and putting 2 and 2 together im suspecting roller followers. The car has always had a tick that the previous owner thought was an exhaust leak (looking back it obviously isnt) and wasnt concerned with so I just went with it. All the misfires were on 6 but now its just 7 which i believe is bank 2 but it did happen one time on 4. Everything is adding up to roller followers but coincidentally the plug on every injector is broken causing it not to lock in. They feel tight but dont click and I saw someone mention that loose spark plugs can cause ticking too so anyone know the torque spec on those? I guess at this point the only way to confirm is to pull the valve covers but just wanted to see if anyone else has had similar problems.
 

whitmanink

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so a few things here.
when something electrical fails ,, it can work fine in the cold \or warm , then start acting up in the cold or warm , they come and go unless a complete failure ,, (ie wire pulled ,broke, ect ect )

so the plugs nots clicking in could do it,, /? (mine are the same tho and i dont have issues )
but that dont mean yours is the same.

when somthing mechanical fails , it fails,, ie (timing chain, rocker arm , roller follower, valve springs , ect ect)

so if a roller follower failed , it would have failed and stayed that way ,
*not starting to act up then got ok , then decided to act up again ..

so it being a roller follower dont add up to me.

i think 12- 15 ftlbs is the correct spark plug torq,

another thing,,
pull the plugs on them cylinders and make sure the spark plug isnt defective.

it could also be a bad coil on plug pac
 

StockishS197

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A failed roller follower doesn’t sound like an exhaust leak, especially if the bearing is bad enough to wear it’s worn into the cam lobe and isn’t opening the valve fully. It’s a very harsh metallic clicking, very distinct from a soft misfire.

And if it was a mechanical issue…the misfire wouldn’t move cylinder to cylinder.

I agree with the above - start with the plugs first and inspect. If those look good, then start looking at pulling valve covers to inspect for mechanical damage.
 

JC SSP

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If the issues on/off it’s not mechanical. This is more likely an electrical gremlin.

Also make sure your alternator is working correctly, grounded properly and all connections secured.

As mentioned, spark plugs and coils should be checked first. Moved them to the opposite cylinders. If it has the issue on the other side that’s your problem.
 

GriffX

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I switched the coil packs around and the problem stays on the cylinder so its not that. Ive been dreading pulling the plugs with all the horror stories of breaking them but looks like I'm out of options. Also here's a video of the car running.
Take a torque wrench and convert it to left hand (easy). Breake the plugs loose at maximum 100 Nm and turn the plugs at maximum 25 -30 Nm. It will take a lot of time but they come out. Turn - click - wait 10 minutes - turn - click...... You squeeze the carbon build up together that's why they stop all the time. A bit of carb cleaner helps.
 

JC SSP

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Plenty of threads on this forum regarding spark plug removal techniques and even the different brands of plugs.

Seek and you will find… lol
 

GriffX

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Plenty of threads on this forum regarding spark plug removal techniques and even the different brands of plugs.

Seek and you will find… lol
A lot of unnecessary fear. You turn them and they get tighter and you still turn them, what to expect?
 

JC SSP

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Agreed but if you break one without the proper tool it could be problematic.
 

StockishS197

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when I bought my car, it still had the original plugs which had 60k miles and about 18 years of age.

I soaked mine with PB blaster and started on a warm engine. Only one broke and the lisle tool (bought ahead of time) worked like a charm.

Reading about it is definitely scarier than it actually happening.

Replace with updated SP547Xs and you will be golden.
 

Ethos395

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Pulled the plugs and not only were they barely hand tight but my 2 problem cylinders have the end of the spark plug missing (electrode i think?) Can i just get a set of new plugs and run it or should i worry about where that electrode ended up? Sense ive already driven the car around for this long I would imagine if any damage was going to be done its already happened.1000010501.jpg
 

StockishS197

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Pulled the plugs and not only were they barely hand tight but my 2 problem cylinders have the end of the spark plug missing (electrode i think?) Can i just get a set of new plugs and run it or should i worry about where that electrode ended up? Sense ive already driven the car around for this long I would imagine if any damage was going to be done its already happened.View attachment 113854
Wouldn’t worry about it. If they were lose, the electrode probably burnt off and even if it broke off in one big piece, it likely went out the exhaust.

Happened to me in my prior 3v and after a plug swap, car ran harder than ever.
 

GriffX

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You got already the latest spark plug revision. (I personally don't like the weld on electrode style plug. Welds are always a weak point.)
 

Laga

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so a few things here.
when something electrical fails ,, it can work fine in the cold \or warm , then start acting up in the cold or warm , they come and go unless a complete failure ,, (ie wire pulled ,broke, ect ect )

so the plugs nots clicking in could do it,, /? (mine are the same tho and i dont have issues )
but that dont mean yours is the same.

when somthing mechanical fails , it fails,, ie (timing chain, rocker arm , roller follower, valve springs , ect ect)

so if a roller follower failed , it would have failed and stayed that way ,
*not starting to act up then got ok , then decided to act up again ..

so it being a roller follower dont add up to me.

i think 12- 15 ftlbs is the correct spark plug torq,

another thing,,
pull the plugs on them cylinders and make sure the spark plug isnt defective.

it could also be a bad coil on plug pac
Spark plug torque on a 05 is 25 ft/lbs.
 

whitmanink

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Spark plug torque on a 05 is 25 ft/lbs.
yea i was going off the top of my head , thats why i made sure to say " i think" ,, lol
but yea, thanks for the clarification . he would definitely have had issues with my torq spec
 

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