OMW in to work this A.M. my upper radiator hose failed. Has about a 1 3/4 - 2 inch rupture in it. No big deal there, i got a ride to a parts store that was close by and replaced it and radiator fluid. After starting the truck and driving a few min. the idle started acting funny.... revving to 12-1300. that leveled out after about 1-2 min. then my oil pressure gauge was a bit high (a little above half ) and my idle was high around 2k. Temp gauge went up to were it is normally, then completly bottomed out. When it came back up the idle dropped to 1k and oil psi. to 1/4 ... everything was as it should be and still is..... Does anyone have any idea WHAT THE HELL was going on? lol Thanks in advance.

 

Air in the system from ruptured hose and adding coolant.

 

OK, i can understand that affecting the temp. guage, but my psi?

 

Your oil pressure should increase with RPMs.
Could it have been higher when the RPMs were high and then dropped back down when the RPMs went down.

 

Oil pressure sound normal to me.

You have an air pocket in your cooling system. Get it burped ASAP before you blow the thing up!

 

ok. here is the question. the coolant system is independant of the oil system in the engine... ERGO a coolant failure shouldnt make oil PSI increase correct?

 

No, but an increase in RPM's (as stated, rose to 2k RPM) WILL cause an increase in oil pressure.

If your truck RPM went UP and your oil pressure stays the same or goes DOWN, you have a problem.

 

right, i got that. My question was WHAT would make my temp gauge bottom out.. and the answer was air... got that. At the SAME time, when temp dropped, OIL PRESSURE became normal AND RPMs dropped to normal. WHAT is the correlation?

 

Coolant flows throught the throttle body if I am not mistaken. As the air pocket works its way through the TB, the TB temperature would increase disproportionately, which could cause an erratic idle, and the idle would then impact oil pressure. This is my guess, but I will defer to the experts.

 

The idle RPM is controlled by a bi-metallic spring that is heated by engine coolant. Sounds like it was just a coincidence that warm coolant hit the IAC (which lowered your idle and oil press) at the same time that an air pocket hit the water jacket your temp sensor is screwed into, making the gauge bottom out.

 

This.


If everything is normal now, it sounds like it was all just because of the air bubble. Make sure you check your system and make sure the coolant level is topped off.

Also, do the burping procedure we talked about in PM.

 

why is everyone's truck facing to the right? (look at the avatars)

carry on.

 

OMG, I was just thinking the same thing in another thread


so here's my avatar, facing the other way, just to mix things up a bit

 

Mine points left.

 

damn i was too slow