99FRC dead cylinder
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99FRC dead cylinder
My 99frc 90,000 miles was idling rough throwing misfire codes so I changed plugs and wires with no luck. Did a compression test and found out that the number "6" cylinder was really low. I pulled the head off and there are no bent valves and the pistons look great. There is no wear in the block. The car takes no oil. I'm wondering if anyone has any suggestions of what could be wrong. Any ideas would be appreciated.
Drifting
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From: bloomfield nj
did you do a wet/dry compression test? you should've done a leakdown test[too late now].now it wll be a little tough.what did the plug look like? you could of had low compression because of ring wash[raw fuel washing the cylinder down].what were your compression numbers?
Drifting
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From: bloomfield nj
Originally Posted by roadtrip120
I'm having the same problem but i haven't pulled the head yet.
My cylinders are 120-140 cylinder-5 is 60.
What can we look for?
My cylinders are 120-140 cylinder-5 is 60.
What can we look for?
put a couple of drops of oil in the cylinder[about a tablespoon],if your number comes up you have a sealing problem[rings/cylinder wall/piston],if it stays the same,your problem is in the head[head gasket/valve/seat/guide/etc].then you can reverify it with a leakdown test.
Last edited by dpd; Feb 3, 2006 at 07:24 PM.
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All of the other cylinders are around 110 #6 is around 30 when you rev it to 1500rpm or more it smoothes out. after a long drive when the motor is real warm you can hear a tick from inside the engine compartment,but not from under the hood. I hooked up a scan tool and injectors and coil/plug,wire are all working fine
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Unless you completely disassemble the head, you wont know if the valve is not seating properly. Try this. Mix 50/50 water and antifreeze and ad the mixture to the combustion chamber of the head. Look for leaks in the intake port and exhaust port. The antifreeze will relieve some of the surface tension of the water and make it flow better if there is a leak path.
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