my 04 trailblazor oil pressure drops to 0 when driving is that bad
...well if it's the instrumentation...we might be okay (sorta) if in fact the oil pressure has dropped, it would not come back (broken shaft, gears)~ I'd look at the system grounding....the 1/0 black battery cable connection to the chassis ground...wirebrush the connection to metal and the lug too~ get good ground to the control panel and the problem will most probably disappear~
...new battery tooo-if older than five~ (knock off labels on the top shows the date of the first charge)~
Install a manual oil pressure gauge, that way you will know if the it is the oil pump or just the sender failing.
any one of these....they aren't too much trouble to install...just be sure the fittings aren't leakin'~
Most likely its the dash gauge stepper motor. When they fail, the gauges act react erratically. I have an '03 EXT with a 5.3l and three of the gauges are acting up. The repair is to send the dash panel out for motor replacement or obtain a replacement panel. http://ezinearticles.com/?Trailblazer-Instrument-Cluster-Repair---1-Odd-Reason-They-Fail-and-the-4-Choices-for-Repair&id=5257758
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