Need help please.
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Need help please.
Truck: 99 F350 V10 CC LB 4WD 4.30 gears, Banks Headers, Volant CAI 83,000 miles.
Problem: Missing, rougher than nomal idle, exhaust manifold leak.
Tried fixes: No CEL light, but recorded random misfires and solid #4 misfire on Snap On scan tool. Replaced all plugs, did not look great with less than 20,000 miles on them (#4 loose again, blew out at 65k miles) Replaced all boots and two COP's. Still runs rough but the mind boggling problem is the exhaust leak. It started out like the classic header gasket leak and now has become a chirp noise? Has anyone experienced this? Will run a compression test on passenger side bank as the noise is coming from that side. Have tried to find a manifold gasket leak with no luck. Could this be a head gasket leak? Burnt valve? This truck has ran perfect in the past, any ideas would be great!
Problem: Missing, rougher than nomal idle, exhaust manifold leak.
Tried fixes: No CEL light, but recorded random misfires and solid #4 misfire on Snap On scan tool. Replaced all plugs, did not look great with less than 20,000 miles on them (#4 loose again, blew out at 65k miles) Replaced all boots and two COP's. Still runs rough but the mind boggling problem is the exhaust leak. It started out like the classic header gasket leak and now has become a chirp noise? Has anyone experienced this? Will run a compression test on passenger side bank as the noise is coming from that side. Have tried to find a manifold gasket leak with no luck. Could this be a head gasket leak? Burnt valve? This truck has ran perfect in the past, any ideas would be great!
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New plug, coil and boot on #4 and still registering miss fires and chirping like a bird. #4 plug may show signs of molten metal on plug. Mechanic friend at a loss, I dropped it off at the stealership, will post follow up. Tried all of the above with no luck.
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From: north west new jersey
metal signs on the plug would mean a piston is melting due to a overly lean mixture.
here with going by your saying you changed the plug, boot and cop pack, i would do a compression test then look into the possiblity of a bad injector or wiring to that injector on that cylinder, that would or could be why you think you may have see some metal building up on that plug. the melting piston would lodge small amounts onto the plug,
as to your popping sound, i would wager on the manifolds being warped and some broken studs found. when these studs break off they allow the manifold to warp and almost every shop or driveway mechanic fails to do the job properly and have the manifolds trued before reinstalling them, hense down the line they again pop the studs and blow out.
here with going by your saying you changed the plug, boot and cop pack, i would do a compression test then look into the possiblity of a bad injector or wiring to that injector on that cylinder, that would or could be why you think you may have see some metal building up on that plug. the melting piston would lodge small amounts onto the plug,
as to your popping sound, i would wager on the manifolds being warped and some broken studs found. when these studs break off they allow the manifold to warp and almost every shop or driveway mechanic fails to do the job properly and have the manifolds trued before reinstalling them, hense down the line they again pop the studs and blow out.
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#4 hole 50 psi, vavle cover is coming off to inspect followers and cam, if all OK head is coming off. This motor has hauled and towed heavy but has never been abused, in fact it has textbook maintenance records since new. What a dissapointment 
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From: north west new jersey
83.000 miles and a disapointment? man i wrenched for 42 years in dealers and think i have seen about all.
get it apart and find the cause. if you were running lean causing the miss fire to be frank you could melt a piston in hours.even less.
to give a example i have seen a piston in a out broad melt in 20 mins times . it was caused by a clogged carb main jet making it run lean.
did you have a vac leak? did you have a bad injector? could be as simple as a bad oring on a injector. that frys a motor. find the cause first as even with perfect maintaince s- - - happens and happens fast. and with polution controls we run right at the point of being lean to start with. make it leaner and things burn up.
get it apart and find the cause. if you were running lean causing the miss fire to be frank you could melt a piston in hours.even less.
to give a example i have seen a piston in a out broad melt in 20 mins times . it was caused by a clogged carb main jet making it run lean.
did you have a vac leak? did you have a bad injector? could be as simple as a bad oring on a injector. that frys a motor. find the cause first as even with perfect maintaince s- - - happens and happens fast. and with polution controls we run right at the point of being lean to start with. make it leaner and things burn up.
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Service manager says chip or crack in exhaust valve possibly do to improper installation of insert for spark plug, insert looked too deep.
Will have machine shop service head and install new spark plug insert and all should be well.
Will have machine shop service head and install new spark plug insert and all should be well.
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Resolution
Since no one hardly ever follows up on thier problems I thought I would post my follow up.
Service manager claims carbon build up on helicoil that was installed too deep probably caused the valve damage. Machine shop installed new aluminum insert, cleaned head and all other spark plug threads. $1,400 later it is running smooth as glass.
Service manager claims carbon build up on helicoil that was installed too deep probably caused the valve damage. Machine shop installed new aluminum insert, cleaned head and all other spark plug threads. $1,400 later it is running smooth as glass.