All the codes in my Chiltons are P-zero codes, none begin with 1. Anybody have any ideas? This check engine light drives me nuts.

 

It pretty much means that it has been overheated at one point or another. Reset the PCM and see if it comes up again.

 

Nope, not overheating at all, in fact, cool as the otherside of the pillow. What is the actual definition of P-1258?

 

I believe its a code that gets displayed after the temperature has gone above a certain point at any time.

 

P1258 Engine Coolant Over Temperature - Protection Mode Active

I believe the "certain point" is around 268 degrees F. Basically, the computer registered that the coolant at some point was over 268 degrees F and went into "protection mode" to try and save itself.

Do not get this confused with the P1258 for Diesel engines, which is different.

 

Well, just replaced the radiator, t-stat, water pump, flushed trans lines and cooler, and added royal purple ice about 300 miles ago when I replaced trans and few other things. Might be the new coolant temp sensor in the new F.I. air gap. It might be screwed in to far and getting to hot? This truck NEVER overheats and has been taken easy since the new work for break-in reasons. Any other ideas?

 

Have you cleared the code and had it come back?

 

Yes, code cleared and nothing yet, only after 20 miles.