Quote:
Originally Posted by Nicole
Interesting - would bad coils make the compression test fail?
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If the coils were acting up while trying to start the car, it would quickly flood because of no ignition. A flooded condition causes low compression because the excess fuel washes off the oil film needed at the seals to maintain a good compression. So if they tested the compression while the car was still flooded, or shortly after un-flooding it, a low compression reading can be expected. Not exactly a conclusive test in this case.
Also agree with Ted that dealer is lame for not giving you any numbers to go with thier "low compression" assessment. Since it's a dealer, I'm assuming they have Mazda's compression tester, which spits out a nice hard copy printout with a graph & numbers for the tech to read. The tech should have given you that as well.
Forgot to add - there are other ways a dealer/mech can screw up a compression test. One of the common procedural mistakes is forgeting to floor the throttle wide open while the car is cranking and the comp. readings are being taken. That would result in a low reading too.
From all the symptoms discussed, the mileage on the car and the failure history on RX8 coils, it sounds like you just have bad coils. Since the coils are relatively cheap (~$30 X 4), I'd take my chances with just buying new ones and having a trusted mechanic install them for you. May well solve your problem for a lot less than $5K/new engine.