2000 F150 4.2L. In cold weather when the engine is cold the instrument panel is showing no oil pressure and the high water temp light is on. After running until the engine is at normal operating temperature the oil pressure gauge is in the normal range and the water temp light is off. Any suggestions as to what is going on?

 

If your truck is like my 98 the cluster is flaking out. I replaced mine and took care of the problem. Be advised mine is a 98 and the GEM does not have to recognize the new cluster.

 

What are the weight and temperature ratings of the oil you're using? When you say cold weather, what is the temperature? Some people don't consider it cold until it gets below 0* while someone in Miami might complain about the cold weather when it's 50*. We need some more info before we suggest anything with any degree of confidence. JMO

 

My 2001 4.2 has done similar to me twice. Both times it was after sitting out when the nights got below 32 deg. farenheit and the truck had been sitting a week or more. It lasted maybe two minutes before the light went out and the gauge jumped to normal readings.

I use 5w20 oil with a motorcraft filter.

I'm wondering if the oil draining back past a valve somewhere or if maybe the pressure switch is just flaky. I have a new oil pressure switch but have not gotten around to replacing it.

 

I'm thinking that because they are both happening at the same time, this is a cluster issue or a ground issue.

Is there anything else wonky going on?

 

I was considering what might be going on with the "until the engine is at normal operating temperature." If a heavy weight oil is being used along with the cold temperature could it be that there isn't enough oil wedge to maintain oil pressure? The 4.2 uses a cylinder head temperature sensor and not an actual coolant temperature sensor. If there is a lack of oil wedge could the cylinder head be getting hot from the lack of the cooling properties created by an oil wedge? I do think it's odd to consider an HEC (cluster) issue that goes away when normal operating temperature is reached. I would find it easier to accept an HEC issue if the problem stayed after the engine warmed up or the issue showing up was consistently inconsistent which it's not according to the OP. What issue with the cluster would only exist from startup to engine warm up? JMO but I think there's more involved than what the OP has considered to be relevant to pass along.

 

I am using 5-30 Mobil 1 synthetic and this occurs after the truck has set for a few days with the outside temperature in the 30s.

 

It's possible that is the problem with this truck also. I will check into having this cluster rebuilt or replaced.

 

I will test the oil pressure with a pressure gauge at the switch location, but it will be a while before I can get to do this.

 

The red Brake light and yellow ABS light are both on but the brake system is working fine. Any suggestions as to where to check for a bad ground?