2005 envoy and p0301 code

[Lincoln]

Just need to know where my oil pressure switch in located on my 2005 GMC Envoy with a 4.2L Vortex 6 cyl Thanks

[ProTech]

The oil pressure switch is located right above the oil filter, attached to the oil filter adapter housing. There will be one electrical connector to it. It's easiest to access from the passenger side of the Envoy, and by taking off the lower engine protection shield.

[papasmurf]

Water temp guage is not working. Has gone beyond 260 and doesn't move when engine is off/on. What is the chance that the guage is shot or the sending unit is unplugged from the engine and if so, where is the sending unit located on the block? I understand this guage is in a cluster and would require total replacement but want to check to make sure that is has not just come loose from the block. Just submitted forgot to give you vehicle.It is 2004 envoy 4.2L.

[ProTech]

The coolant temperature sensor is located on the left side of the engine, behind and a bit under the alternator. It's easiest to replace if you remove the alternator first. The connector is actually a bit farther from the sensor, as the sensor has a harness coming off it. You can check to see if it's unplugged pretty easily. Either way, if it's not just unplugged, you're going to be looking at a sensor replacement or cluster replacement.

[Bunkie]

Can you tell me how to properly drain antifreeze from a 2000 GMC 1/2 ton truck with a 5.3L engine?

[carriedi]

well, you could drain the coolant from the petcock for the radiator. Check for engine block drains on the side of the block. Let gravity do it thing. you could take it to a shop that has a coolant exchanger where they push coolant through the thermostat housing and force the old coolant out the radiator hose. (this way you don't get air in the system that you have get out) Or if you do drain all the coolant out you could use a tool to evacuate all the air out and then the vacuum in the system sucks the new coolant in.

[fisherman563]

2005 envoy with 127k miles. Changed the plugs and put in a new coil in cylinder1. Still have the issue, next I took out the throttle body and cleaned that and while I was at it switched coil 1 and 2 even though I put a new coil in 1just to see if the new coil was the problem. Still have the same issue code P0301. Any thoughts as to what to try next? Thanks for any help.

[carriedi]

if you change the plug and coil for number one and still have the misfire for #1 you should look at the injector. If you switch #1 injector with the next one closest in the fuel rail, then check to see if the miss follows the injector or stays in #1. If it switches then you have a bad injector. If it stay on #1 then I would look for a mechanical problem with #1

[guest]

the truck has been siting for a few years and i have changed a freeze plug under the passenger side of the engine under the motor mount, and while filling up the radiator and reservoir to check if the freeze plugs still leaked and coolant started leaking from the driver side front of the engine. I can't find the leak, and I can't remove the engine to identify the problem.