89 b2 running too cool

[dragster557]

When i first got it i put a new temp gauge sending unit in it and the gauge read straight up between the r and m in normal just like all fords i have had.I then put a new explorer radiator in and a new 195 thermostat an now it runs on the n.I worried that it is too cool and that is why it only gets 9.75 mpg delivering mail.Any thoughts.Thanks

 

[adsm08]

I think you are right.

Take that ridiculously large radiator out and put the one it was meant to have back in so you stop flooding the engine with cold coolant every time the t-stat opens. Your MPG might go back up a bit. Not that you will get great mileage delivering mail.

 

[The_Dealer]

get a sunpro guage from advance for 12 bux and make sure its running too cool...i dont see how too cool of temp will give u bad gas mileage. i thought it just had to do with pinging and timing. a rich a/f ratio will make it run cooler. i have an exploder radiator and 180 stat and it runs at 190-200 on the reg

 

[kimcrwbr1]

Sounds like somthing other than the radiator maybe the t-stat was in the wrong box put the old stat back in if you have it and see what happens the radiator cools the coolant and the stat controls engine temp if the coolant is colder the stat wont open as far. You dont say what engine you have, try cleaning the IAT or MAF sensor and reset the computer by disconnecting the battery for 1/2 an hour and see if that helps with the fuel mileage.

 

[Shran]

i dont see how too cool of temp will give u bad gas mileage. i thought it just had to do with pinging and timing. a rich a/f ratio will make it run cooler. i have an exploder radiator and 180 stat and it runs at 190-200 on the reg

Your coolant temp sensor has a dramatic effect on mileage. If it sees cold antifreeze, it will dump a lot more fuel. Had the same problem the OP has.

The 4.0 radiator is a great upgrade for a 2.9 powered trail rig, but in a daily driver it is a bad idea... I have done this in two different Bronco II's with the same results.

 

[adsm08]

Your coolant temp sensor has a dramatic effect on mileage. If it sees cold antifreeze, it will dump a lot more fuel. Had the same problem the OP has.

The 4.0 radiator is a great upgrade for a 2.9 powered trail rig, but in a daily driver it is a bad idea... I have done this in two different Bronco II's with the same results.

This is exactly how running too cold gives you bad mileage.

The way the engine works is that the air in the cylinder heats and expands when the air/fuel mix is ignited, pushing the piston down.

A cold engine will suck that heat from the air, meaning that you need more fuel to make the same expansion effect.

 

[The_Dealer]

Your coolant temp sensor has a dramatic effect on mileage. If it sees cold antifreeze, it will dump a lot more fuel. Had the same problem the OP has.

The 4.0 radiator is a great upgrade for a 2.9 powered trail rig, but in a daily driver it is a bad idea... I have done this in two different Bronco II's with the same results.

i was thinkin of a 2.8

 

[Shran]

Pretty sure that even a 2.8 with the stock computer and ignition has a coolant temp sensor. Anything older than that and is not fuel injected would not matter though.

 

[dragster557]

It is a 2.9.The thermostat was stamped 195 but it could be made wrong.I put this radiator in because i bought it just for mail and i read alot about these over heating and how people were doing this.So i was trying to make it dependable.It has a map sensor instead of maf.Thanks

 

[adsm08]

You dont say what engine you have

Well they only put the one engine in the 89.