Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum banner
1 - 6 of 6 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter · #1 ·
My 2003 Trailblazer (approx. 120,000 miles) oil pressure gauge just starting malfunctioning.

Originally the gauge would turn to 0 at shut off and run about 40 at idle and running speed.

Now the gauge sits at 40 at shut down and runs well over the 80 mark when running.

I don't trust the gauge anyhow and have read previous posts that the gauge is a glorified idiot light.

Could this malfunction be a sending unit or is there a way to reset the gauge to reset to zero at shut down?
 

·
Banned
2004 gmc envoy_sle_xl
Joined
·
1,239 Posts
The gauges are driven by small stepper motors in the dash, I think these have been known to fail. Since you're reading 40 at shut down and 80 with engine running, it's fair to say you probably have 40 lbs of oil pressure. The stepper motors are controlled by the ECM, but that's not likely the problem.
You can find the motors on Ebay and if you're handy enough, you can replace it. It think there are instruction on the site somewhere, do a search. Good luck.
 

·
Registered
2006 chevy trailblazer_lt
Joined
·
179 Posts
It sounds to me like it is one of those very well built quality stepper motors. They are a known failure in these vehicles. There is a very well written how to on how to replace the individual stepper motors. Otherwise, a new unit costs about 700.00! Let us know how it goes.
 

·
Registered
Joined
·
3 Posts
Almost Same problem here

Hey guys, i have a 2003 Chevy trailblazer. and yesterday i noticed that my OIL GUAGE goes all the way to the max past 80 when i turn the car on and when i turn it off it goes to zero as all the other guages.
even on idle it is all the way to MAX
what could the problem be ?
thank you
 

·
Banned
2004 gmc
Joined
·
26,181 Posts
Could be the gauge stepper motor failed or the oil pressure sensor, or less likely, the oil pressure really is that high and you have an oil pump problem that will soon start popping seals and gaskets. Get a mechanic to hook up a scan tool that can read the true data as measured by the oil pressure sensor. If the data is good, the display needs a repair ($100 or so by an Ebay vendor, $10 if you can solder it yourself.) If the data is bad, they need to dig into the reason.

Before anyone chimes in, this is a V8 with the true analog sensor, not the I6 with a switch. It was posted in the wrong forum.
 
1 - 6 of 6 Posts
Top