An easier way to do a cylinder balance test:
Get some 1/4" vacuum hose, and cut 1/2' long pieces, cut six of them. Put
one under each boot at the coil end of the plug wire, and push them up
equally, then put the plug wires back on to the coil. I advise doing this
one at a time.
Then get a good 12 volt test lamp, ground the alligator clip, and go near
the opening of the boot one by one, and observe the drop in the engine RPM
by ear. But, don't do this too long, you'll toast the catalytic converter.
This will tell you which cylinder makes less of a difference.
Also, it is possible to cross the wires on the same coil, and not have a
total miss, but a slight miss. Get a compression tester, if the compression
is good, start looking for loose vacuum lines and spray carb cleaner lightly
around all the vacuum lines and throttle body and areas around it.
Be careful with the carb cleaner too, too much will hit the catalytic
converter, and your will kill you if you turn the car into a Tostito!
I hope this helps?
The procedure describes installing short lengths of vacuum hose
in series -in- the secondary circuit. (Vacuum hose will conduct
secondary current.) The pieces of vacuum hose will give you an
exposed place where a grounded test light can be touched,
shunting the secondary current to ground thru the test light
effectively allowing the secondary to be canceled to that a
cylinder balance test can be performed.
Short pieces of hose:
So that the wire doesn't seat fully, and when you use the test lamp. It
grounds the spark, in effect working like a cylinder balance tester.
then when you're done, take out the short pieces of hose from "inside the
Let us know if the " doctor " pronounces her dead.......
1991 Pontiac Bonneville LE
3800 V6 ( C ), Black/Slate Grey
~~~The Former Fleet ~~~
89 Cavalier Z 24 convertible
78 Holiday 88 coupe
68 LeSabre convertible
73 Impala sedan
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