Hello everyone I have a 2003 Excursion 6.0. I didn't post this in the 6.0 section because it may not be just a 6.0 issue. On cold starts, anything under 150 degree water temp reading on the SGII. I get a CHECK GAGE light on accompanied by the check engine light. No codes read on the SGII pending or stored. Just some of the time I get a water in fuel light too. This tends to go out fairly soon after driving. (Even after I just drain the fuel pump it still happens.) other issues that accompany the lights are as follows.
The trans temp does not give a reading to the dash. The oil temp does not give a reading the dash. Both show proper temp on the SGII. When in reverse the back up alarm beeps as if something is behind me. And the auto door locks will not activate after 10 mph. The tach also will not show a reading in the dash. SGII shows the numbers. Now the kicker, this ALL gets resolved the instant the water temp hits 150 degrees. The only lingering issue is the that the tach will surge or drop every now and then. The tow/haul light does not come on when this is going on. Anyone have any ideas? I've checked the battery terminals all are clean. Both batteries are brand new. thanks for your time

 

Just a bump since I posted late. Hoping to get some exposure. Anywhere else I can post this that may get more traffic from electrical gremlin gurus? Thanks

 

Probably wouldn't hurt to post up in the 6.0 section. There's a lot of knowledgeable folks down that way. They'll at least ask you some intelligent questions!