1999 Oldsmobile Alero Misfire

12,500 MILES • 6 CYL • FWD • AUTOMATIC
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LGOODEN
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I have a 1999 Alero, Cylinder 5 misfire. Ploblem is when I torque down the rocker arm it loses compression. It their a fix. I've had my head service three times.
Sep 29, 2008 at 1:49 PM
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OBXAUTOMEDIC
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[quote:7e6b17b69c="lgooden"]Engine Performance problem
1999 Oldsmobile Alero 6 cyl Front Wheel Drive Automatic 12500 miles

I have a 1999 Alero, Cylinder 5 misfire. Ploblem is when I torque down the rocker arm it loses compression. It their a fix. I've had my head service three times.[/quote:7e6b17b69c]

Hello,

In most cases when a cylinder missfire is set, the fix is to check the simplest thing first.

Check Plug and wire check coil check injector
Sep 29, 2008 at 1:55 PM
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LGOODEN
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I've replaced spark plugs, head job three times, With a compression tester installed, the problem accures during torque of the rocker arm, with the tightness of my hand it ok, as soon as I put a torque rench on it the compression lowers, at 14 ft pounds w/ or w/out a quarter turn. I loose compression on that cylinder
Sep 29, 2008 at 2:32 PM
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OBXAUTOMEDIC
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[quote:7c364aaec9="lgooden"]I've replaced spark plugs, head job three times, With a compression tester installed, the problem accures during torque of the rocker arm, with the tightness of my hand it ok, as soon as I put a torque rench on it the compression lowers, at 14 ft pounds w/ or w/out a quarter turn. I loose compression on that cylinder[/quote:7c364aaec9]

Does the rocker arm look worn?

Have you tried changing out one of the other rockers to see if it changes to another cylinder.

If it does replace rockers.
Sep 29, 2008 at 2:39 PM
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LGOODEN
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Yes, the rocker arm looks mine, I've had a mechnices look at them, It a long shot but I'll try to replace the rocker arm.
Sep 29, 2008 at 2:58 PM
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LGOODEN
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I've chancged rocker arms, still same problem, what our the chances that the lob on that cylinder is bad, or worn, if so changing new heads would not help

Thanks for your feed..
Sep 29, 2008 at 4:55 PM
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OBXAUTOMEDIC
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One other thing to check if you haven't already....

The Lifter, if it is frozen or stuck then it will cause your problem also.....

I don't remember if the push rod hole is big enough to pull the lifter out through it.
Sep 30, 2008 at 6:38 AM
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LGOODEN
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I'm checkin or redoing a zero lash step
Sep 30, 2008 at 1:20 PM
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