OverHeat Fixed then New Problem with gas?

[sleeper07]

Hi I just repaired my car its a 95 240sx I changed the water pump, clutch fan, and thermostat about a week ago I used my air con. when it was like 90 outside. When i can home there was no more antifreeze. After i filled her up I drove it for about 10 mins. it started to overheat again... i touch the top Rad. hose and of course it was hot. Then when i checked that bottem hose it was ice cold. So i relized that the thermostat that i just changed went bad. I figured that i didnt need it.

Now This is that problem... I filled up my car about $32 of gas and now im only getting like 150 miles!? Do u think i should buy another thermostat? I don't know what too do. Thanks for your time and help.

[GSX running]

are u sure u water pump is good, and I don't think ur thermostat would cause u to get that bad of gas milage

[sleeper07]

Water pump, Clutch fan, Thermostat are all Brand New.

[dickie]

did you put your thermostat in backwards? hey, it happens more often than you think!

maybe next time buy the nissan oem part from the dealer?

also, did you properly burp your coolant system after filling it?

[sleeper07]

I am sure i installed it right with the jiggle value up. And i bled the weep hole. My friend helped me he's a auto mechanic at Lexus. Maybe i should buy a OEM Nissan thermostat?

[sleeper07]

HELP PLEASE!

[dickie]

i would say if you have ruled out all other causes of overheating, you should indeed pick up an OEM thermostat as the ones you buy from the auto parts stores tend to have a failure rate somewhere in the neighborhood of 30% out of the package (personal experience and others' testimony).

a way to make sure that the thermostat is indeed the issue: take it out and run the car to operating temp without it. still overheating? you have more issues

i followed the FSM procedure for pruging air from the system 5 times before it stopped overheating. try the easy method: park at a steep incline and remove the radiator cap, then run the car until all of the bubbles in the system have escaped. top off at filler cap as necessary.

[sleeper07]

Alright thanks i think its the thermostat but can that be a the problem with the gas? Because i took off the thermostat and im getting crappy gas mileage now. I live in San Diego it never really gets super cold here.

[dickie]

gas mileage will suffer at higher engine temps, i believe, but it shouldnt affect it as much as that.

thats less than half the normal fuel economy, are you sure the car is actually running that low or could it be a gauge issue?

have you checked for fuel leaks? timing could be way off.

[ltspureluck]

these new parts oem?

[drmerdp]

Removing the thermostat will keep you below operating temp and in open loop. (think of cold start up, enriched fuel mixture....) Put it back in