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Normal engine temp in SOHC 2.5L H4?


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Does anyone with OBD2 scanner/interface or digital sensor can tell me their engine temp? Mine is 180F while driving on hwy (75MPH) and 187F or so idling during summer (AC off).

I am troubleshooting my poor MPG and exploring all possibilities (I covered all common things, you can search for my posts). Maybe the thermostat is set on a low-normal end and a 10F bump up would improve MPG?

Thanks!!!

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The book lists the thermostat "starts to open" temp as 172*F and the fully-open temp as 196*F.

 

184*F falls right in the center, so I'd say your coolant temps look normal.

 

One thought would be to use the scanner to check for ignition retard while driving. If the timing is getting bumped back for any reason, that'll kill your fuel economy.

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Does anyone with OBD2 scanner/interface or digital sensor can tell me their engine temp? Mine is 180F while driving on hwy (75MPH) and 187F or so idling during summer (AC off).

I am troubleshooting my poor MPG and exploring all possibilities (I covered all common things, you can search for my posts). Maybe the thermostat is set on a low-normal end and a 10F bump up would improve MPG?

Thanks!!!

 

 

What is your current MPG city and hiway (be truthful;)? 75mph will certainly

lower it compared to 60..that's a big given. My 03 2.5L get's approx 29mpg hiway at 62mph but still only 19mpg city,if I increase speed to 70 my mpg drops to 24.

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The book lists the thermostat "starts to open" temp as 172*F and the fully-open temp as 196*F.

 

184*F falls right in the center, so I'd say your coolant temps look normal.

 

One thought would be to use the scanner to check for ignition retard while driving. If the timing is getting bumped back for any reason, that'll kill your fuel economy.

 

Thanks, timing advance seems OK: 15 degree on idle and 30-40 cruising.

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What is your current MPG city and hiway (be truthful;)? 75mph will certainly

lower it compared to 60..that's a big given. My 03 2.5L get's approx 29mpg hiway at 62mph but still only 19mpg city,if I increase speed to 70 my mpg drops to 24.

 

Your post is very refreshing. People usually boast about record MPG but do not disclose how slow they go.

City: 16-18, Hwy 23-25 (70-75 MPG) or 20-22 (80-90 MPG).

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the scanner should be able to show you real time gas milage. Be interesting to see how it varies..

 

 

 

nipper

 

The inteface I use does not report MPG, but it can be calculated from airflow and speed. The maker of the interface is revising the software for me to make the calculation in real time.

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Your post is very refreshing. People usually boast about record MPG but do not disclose how slow they go.

City: 16-18, Hwy 23-25 (70-75 MPG) or 20-22 (80-90 MPG).

I gotta agree, your numbers seem kinda low.

 

With reasonable driving, my city mileage is 23 (summer) / 21 (winter).

 

If I hold to 70 mph, I'll return 27 mpg highway (A/C on 50% of the time).

 

What kind of tires are you running? When I switched off the original RE-92 for RE-950, my mileage dropped about 5%. Cornering improved 100%. :D

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I gotta agree, your numbers seem kinda low.

 

With reasonable driving, my city mileage is 23 (summer) / 21 (winter).

 

If I hold to 70 mph, I'll return 27 mpg highway (A/C on 50% of the time).

 

What kind of tires are you running? When I switched off the original RE-92 for RE-950, my mileage dropped about 5%. Cornering improved 100%. :D

 

I also have RE-950. This could contribute to the problem since RE-92 are low rolling resistance rated (like most OEM tires) and RE-950 being high performance are not. However, I keep them inflated to 40 PSI that should more than compensate for the difference.

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