2007 Tahoe oil pressure gauge

[DWood]

I have a problem with the oil pressure gauge goes almost to 80 when the key is turned on then when the tahoe is started it peggs past 80 but when shut off it drops to 0 and sometimes while going down the road it goes to 0 then back up. NO alarms the readout doesnt say anything and unit is full of oil. Whats the easiest way to determine if its the sending unit or the cluster.

 

[clkelley]

That sounds like the cluster, if it is pegging 80psi before the engine is started then it is more than likely the stepper motor. The sending unit doesn't have any information to send until the engine is started.

 

[DWood]

thank you

I thought it was probably the cluster since the ecm isnt trying to shut it down and i dont get a message on the display saying to check the oil. How hard is it to replace that cluster and is it expensive?