I drive a 2004 1500 quad cab, with the 4.7l engine. Today, my check engine light came on. Shortly after, when I came to a stoplight, the Check Gauge light did also. It sounded every 4-5 seconds, and only stopped when my truck began moving. It didn't come back on again until I stopped at another light. Any ideas why this would have happened? Something that can be repaired at the house, or should my mechanic handle this?

 

Check gauges means that. On of them is trying to tell you something. Need to know which one.

 

OK, I had the code checked at autozone. According to the rep, my #4 cylinder was misfiring. He suggested I replace the spark plug for starters, and see if that fixes the problem. I did that. Do I need to do a reset to get the check engine light to go off? FYI, the Check Gauge hasn't gone off again since the first day..

 

Don't change just one plug. If there are more than 40K or 50K on the plugs, they're due anyway. Many times, a warning on a stop can mean low oil.

 

A cylinder misfire could be an issue with the fuel injector for that particular cylinder, the cylinder's coil, or the spark plug. One way to test is to swap the coil with that on a neighboring cylinder and see if the problem moves to the other cylinder. If the problem remains, return the coil packs to their original cylinders and swap the injectors to see if the problem moves. If not, return the parts to their original locations and pull the spark plug.

 

I changed all the plugs, fired her up. Light's still on. I also noticed white smoke coming from the tail pipe??

 

Sounds like you over heated it. The 4.7 doesn't like being over heated at all. The reason I say that is because of the white smoke. That usually means you blew a head gasket

 

A head gasket replacement sounds expensive, but I'll have to have it looked at. Thanks guys.

 

You had a #4 cylinder misfire. Did you have any signs of an overheat situation? I don't recall you saying your temp gauge showed an overheat, or you lost coolant, etc. Did that occur?

Clear your codes (you can pull the PCM fuse to do that) and see if stays off.

Check your coolant level and check for oil in the coolant or coolant in the oil. If you had a misfire, that should not have caused an overheat.

 

Don't have an overheat issue, just white smoke out the pipe, and a yellow/whitish buildup on the bottom of my oil cap. Also, I have a slight hesitation that goes away after the engine warms up. These may all be related, or​ none. I have no idea.