Temp gauge rises under load, lowers at cruise/idle

[tjg8675]

I have a 95 bronco

5.8L 351ci

aftermarket off road exhaust

I recently replaced a check valve hose

(not sure of proper name for this, ~it feeds from the exhaust back to the engine. I replaced the first small 6" hose coming directly off the exhaust pipe

located after the Y tube but before the cat *hose not stock*), the old one melted off.

Q - was this a bad thing (heat damage from another problem) or was it just old/worn?

Q - could this have caused/resulted in blocked check valve?

As I mentioned in my topic, the result of the above issue(s) is my temp gauge rises under load, lowers at cruise/idle (up hills - temp up , cruise flat ground - normal)

also seems to be a boggy above 2500 rpm)

Q - Is this OK to drive?

my mechanic has been giving me the runaround for 3 days!!! used to be monster now feels like old taxi cab

Please Help

Many thanks

 

[famousguy_fsas]

dont know about the check valve. but as far as i know its normal for the temp to rise when underload and be normal when cruising and at idle. it gets hotterr under load cause your engine is at higher rpms and moving faster causing more friction heat which will cauase your temp to rise. and when cruising and idle your engine isnt under stress and will run at a lower temp.

do you have a after market guage or the stock one. i would get a after market one cauase it will tell you exactly what ur truck is running at. to my knowlege your truck should be around 195 degrees or lower .when it gets up in the 200s that when i would say u have a prob. as long as when its heating up when you say your putting it under a load it doesnt go over 200 or so i would say its safe to drive. and this is bases on my 5.0 it never goes that high. im always at 190 195. but you having the 5.8 might be cooler causue when i had the 5.8 it always stayed way cool unless my guage was broke and i didnt know it haha. this is just my 2 cents. if im wrong anyone please feel free to correct me

 

[tjg8675]

Stock temp gauge, before melted hose the temp was ALWAYS steady at the "o" in NORMAL,

now goes from N to M rises under load, lowers at cruise/idle

also power loss and sounds bad above 2500 RPM

I will look into a aftermarket gauge though

thanks for the reply

 

[famousguy_fsas]

yeah without that guage you really have no clue what the temp is at. i beleive thay are cheap and easy to install. my 5.8 on my 87 the temp never went past n in normal so you might have a prob.

as for the lack of power and sounds bad. i just had the prob in my new bronc i just bout and it turned out to benothing more than one of my spark plug gaps was completely smashed.

whats it sound like? like its running out of gas?

 

[tjg8675]

Exactly like its running out of gas!!!

I've been trying to pin that explanation down

All I could come up with is it sounds like an old beat up taxi cab

will check plugs

Thanks again

 

[famousguy_fsas]

if it sounds like its running out of gas then i would say check the fuel filter since thats a cheap and easy fix. it only takes a few min. its possible that over 2500 rpm that because your truck is demending more fuel and if you have a dirt fuel filter that its not able to let enough through and its causeing it to bog down. but before you do that run a good bottle or two of fuel system cleaner through to clean it all out and that wya any crap in the tank or lines will be caught in the old filter and not the new one. then put the new one on. and if that doesnt work then that would lead me to your fuel pump same as the filter. if when your truck is demanding more fuel and your pump is old and going bad it cant suptly the gass fast enough. but that a more expensive and harder task to do then the filter so try the filter first.

 

[fordman]

could be your cat. converter is plugged , that would explain the burnt hose and the lack of power and the temperature rising under load.

 

[bigbluebronc]

sounds like he replaced a o2 sensor that might have melted( well the wires)(what else is between the y and the cats) he needs too reset computer(make sure you have the correct o2 sensor) and drive

BBB

 

[tjg8675]

Turned out to be 2 bad cats

Its a roaring beast once again

Thanks all