What's wrong with my engine?
#1
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What'* wrong with my engine?
Well I got to checking around on my 94 SSEi today to see which pulley was going bad since it was making a nice ticking sound at idle. Well after removing both belts I realized that the problem is not there but in the engine itself. #6 cylinder is making a noise from the valve cover area instead. Hopefully it'* just a simple fix but now I understand why I was getting a weak cylinder reading with the scan tool on this cylinder. I'll probably run a compression test to make sure and know what the problem is before I start tearing it down. Anybody else have any ideas what it could be. Maybe it'* just a noisy lifter or something I dunno.
#2
DINOSAURUS BOOSTUS
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Interesting problem. For the most part the 3800 doesn't suffer from head or valve issues. At 13X,000 your car isn't considered high mileage.
What octane of gasoline are you using?
Was the car overheated to your knowledge?
Any ideas on the oil change schedule that was used?
Is the car using any coolant? (slow leak you can't find)
What octane of gasoline are you using?
Was the car overheated to your knowledge?
Any ideas on the oil change schedule that was used?
Is the car using any coolant? (slow leak you can't find)
#3
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I'm using 93 octane gas it'* using no coolant and i've changed oil once. I"m gonna have the engine flushed and see what that does.
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Well I went and had the oil changed today. I used a K&N oil filter and my pressure is about 10psi higher. The engine is still making a knocking sound from the #6 valve cover. Anybody else have any ideas. The only thing wrong with the car is it kinda hesitates when cold and after a couple of minutes it runs great.
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One of the best indications of an engines mechanical condition is the compression test. To do it properly you have to test all cylinder and compare between them. There should not be more than 15 psi difference between the highest and the lowest. I don't really pay attention to the actual reading just the difference (ie something wrong with that cylinder.
An even better tool is the flowmeter. Compressed are is run through the cylinder (spark plug hole) at top dead center of the compression stroke (ie both valves are shut). It has a gauge that measures the percentage of air lost. If too much air is leaking by you can listen in the intake (bad intake cylinder), the exhaust (bad exhaust valve) or the crankcase (throught the oil dipstick(bad rings)).
Sometimes you just have to pull the valve cover off and look at things like the rockers and valve springs. I have seen valve springs broken that give a slight miss and put the check engine light on for a bad cylinder. Start with the compression check (easiest) and then go to the more invasive testing. How does the spark plug look from that cylinder? Could it be a shorting ignition wire making an arc by the head? Start with these.
An even better tool is the flowmeter. Compressed are is run through the cylinder (spark plug hole) at top dead center of the compression stroke (ie both valves are shut). It has a gauge that measures the percentage of air lost. If too much air is leaking by you can listen in the intake (bad intake cylinder), the exhaust (bad exhaust valve) or the crankcase (throught the oil dipstick(bad rings)).
Sometimes you just have to pull the valve cover off and look at things like the rockers and valve springs. I have seen valve springs broken that give a slight miss and put the check engine light on for a bad cylinder. Start with the compression check (easiest) and then go to the more invasive testing. How does the spark plug look from that cylinder? Could it be a shorting ignition wire making an arc by the head? Start with these.
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ThePro696
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