No Start / Compression Problem

2002 MAZDA TRIBUTE
128,236 MILES • 6 CYL • 2WD • AUTOMATIC
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HUMPHRIESONE
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I have a 2002 Mazda Tribute LX, 3L Engine, with DOHC's. It stopped running awhile back and hasn't run since then. I did a spark test on it and found that all six cylinders were getting a spark. I tested the fuel system and the fuel pump was pumping fuel. After doing a compression test on all six cylinders I discovered this:
Cylinders 1 & 2 had 30 psi.
Cylinder 3 had 37 psi
Cylinders 4 & 5 had 0 psi and
Cylinder 6 had 150 psi which is which I've been told is in the range the compression for all six cylinders should be.

My questions are:
Does the 0 psi of cylinders 4 & 5 indicate a blown head gasket between those two cylinders and possible broken or badly damaged valves?

Also, are the low compression readings in cylinders 1, 2 and 3 indicative of valve damage and a blown head gasket also?

I am a automotive tech student with limited diagnostic experience and I could really use some expert input. I really need to repair my vehicle and get back on the road. Any help that anyone qualified to comment on my dilemna will be well appreciated.
Jan 6, 2011 at 3:50 AM
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DOCHAGERTY
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Zero compression in 2 cylinders would typically mean the heads need to come off. Whatever else happens, the engine has some internal issues and an inspection(read: removal of both cylinder heads) is called for straightaway.
Jan 6, 2011 at 6:02 AM
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FIXITMR
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did you overheat it when it stopped running? seems odd that so many cylinders are low for no reason? that low of mileage should not cause timing chains to fail. and what's awhile back? maybe the valve seats are rusted and leaking causing low readings?
Jan 6, 2011 at 8:28 AM
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DOCHAGERTY
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We sometimes have to piece together the story, we are often told just part of what happened.
Jan 6, 2011 at 3:06 PM
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