Engine coolant temp sensor. You should only have one, on the drivers side of the thermostat housing, in the intake manifold.

 

Replaced pump yesterday. Seems to start up fine when cold. Still runs rough till it warms up. Should i replace the engine coolent sensor .. its only $10

 

It's a cheap try, for sure.

 

If you can get to it, it's not a big deal to change it right out on the engine without draining the coolant. You won't probably lose enough coolant to even worry about. Removing the alternator should make it very easy to get to.

 

I was riding through the woods yesterday. Not sure if this made my truck throw a code. I got a code p0138 High voltage on 02 sensor. I know the wire hangs down. Wondering if maybe a branch hit it, or if this has been why my truck has been running rough.. I cleared it and it hasn't come back on yet.

 

That code is for the post-cat O2. It shouldn't affect how the truck runs. (of course, that doesn't mean it doesn't.......)

How did you clear the code?

When does it run rough?

 

I cleared the code with a code scanner. It runs rough until the truck is warmed up.

 

Have you change your plugs again yet? Or, the temp sensor?

 

Still have the plats in there.. It was running bad before that too.. And temp sensor i was going to look into..

 

Our trucks don't really care for the high dollar plugs..... I wonder if you didn't have more than one problem..... and may have fixed one, but, introduced another? Plugs are cheap and easy though..... might wanna try that first, and see if it doesn't improve anything.