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Symptoms of a bad valve seal or worn guides

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Old 07-12-2008, 08:24 PM
  #1  
Alero99
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Default Symptoms of a bad valve seal or worn guides

how does teh car react...

i been having a CONSTANT MISS, can't locate the cyl its missing in

done almost everything to correct

Cap
rotor
plugs (.55)
Pump (190lph)
fuel Filter
ACT
ECT
MAP (its a SD not MA)
TPS adjusted to .96 (not replaced)
02s (bkk Extensions)
FPR (42 psi with vac off)
car pulls 19lbs of vac at idle and around 22-24 at 2500rpms-4000rpms
New Gaskets...
IAC close
EGR deleted
Smog deleted, tubed welded shut, ect ect.
Wires

narrowed it down to...

COIL
Dizzy not being properly installed, but the motor is completely stock so i doubt is ever been taken out.
TFI mod.
SD computer is shot?

Already looked at the pistons, cuz I took the engine apart for new gaskets and cleaned the heads and pistons and U/L intake with intake cleaner
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Old 07-12-2008, 09:26 PM
  #2  
mjr46
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Default RE: Symptoms of a bad valve seal or worn guides

well for one have you done a compression test on all cylinders?? that'll rule out an internal problem.....also un plugging an injeector one by one can locate the prob cylinder.. by finding the cyl where no load change is detected when injector is un plugged..same can be done with ignition wires
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Old 07-12-2008, 09:58 PM
  #3  
94StinkinLincoln
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Default RE: Symptoms of a bad valve seal or worn guides

the coil and tfi will make them all run bad or not at all.
the dizzy pip sensor wouldnt let it run at all either, you replaced the cap, rotor and plugs so i dont see that being the problem if it runs.

pull a spark plug with it running, if the miss changes- then that cyl doesnt have the problem, if it stays the same, thats your problem cyl.
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Old 07-12-2008, 10:04 PM
  #4  
94StinkinLincoln
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Default RE: Symptoms of a bad valve seal or worn guides

if a valve was not seating properly it would cause a miss.
i just helped a guy at work w/ his lightning. he knew he had a miss and he was going to put a built motor in and get his intake ported. well when we pull the intake, #6 intake port had alot of carbon/oil buildup in the intake port, thats where his problem was at.
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