5.9l Not eaching Engine Temp.
 

opps hit the button while I was editing the title. It's NOT REACHING the 195 temp.


My '99 1500 4x4, 5.9l auto. 86k miles. I installed a Hughes FI AirGap intake last fall and it runs like a raped ape.

BUT the truck has been running cooler and cooler and MPG falling all summer like the thermostat is stuck open, so I changed the thermostat with the 195 deg and the temp sensors, BUT its still running cold maxes out at 180, I am driving up to my cabin tomorrow see if it gets any warmer.

Would a bad clutch fan (stuck on) keep the engine from getting to the 195 deg.? Or is there some secret I never heard of.


And now that winter is here I gotta get the heat working before the deep freeze hits. My heat has been minimal, but today after messing with the heat knob, I got the heat to start coming up. Went from its 95 deg to 140+ deg after messing around with it. I think the Heater control panel needs to be replaced.

Best place to get a new one?

For parts either a junk yard or LMC truck.

Even if the fan was running solid, (seized up.) The thermostat should still get the engine to its rated temp. Sounds like a bad 'stat.

What are you using to determine engine temp?

OBD II reading the live engine data. Also visibly lower on the extremely accurate factory gauge.:icon_bowrofl:

this is the 3rd stat since installing the Hughes, I cant believe that I would have gotten 3 bad thermostats. New one is a Saint SuperStat.

Testing the one I replaced opens at 195 deg.

Change the temp sensor.

I picked up a BWD (have a Duralast now) yesterday on my way back from up north, this will be #3 also but different brand.


Maybe I should use the old one out of the old kegger.

I was thinking temp sensor also. What part did you get that's #3? Also if you can get an IR temp gun or something to try and check the engine temp to see if it seems accurate.

Well replaced the Sensor, But I had it backwards last two sensors were BWD.

So I changed it up and went with the duralast. Showing a little warmer 187deg at idle.

Definitely up on the factory gauge.

After messing with the heater lines had some sludge in the system. Time for a full system flush.

Renting so don't have access to a decent water source.

One would think finding someplace to do an true coolant flush & clean wouldn't be such a task.

All the local joints just drain the radiator fill with distilled water run it, drain and fill with antifreeze. They call it a flush & clean, just a crappy flush if you ask me.

The only place I can find to do a real clean and flush is about 40 minuets north of me through a bunch of road construction (that by the way NEVER ends here in Milwaukee)