2002 Forester CEL issue

[dave_anto364]

Hi All,

Tried searching the posts and got some ideas but I keep getting the same CEL -
1490. Was told this is a Subaru Tech code, not listed in my haynes manual. Some
of the fixes are - change thermostat (done), change engine temp switch (done -
had to use OEM, aftermarket did not work).



So here is what has happen, bought car fro local used car dealer. Inspected and
passed with no codes. Within 100 miles 1490 pops. After research, I have dealer
replace thermo. Then within another 100 mile the 1490 pops again - fans were
acting suspect and temp was rather high. Dealer changes temp switch. Code pops
within another 100 miles and temp still high. Dealer says he used after market
temp switch - replaces with OEM and also replaces battery. Car goes over 300
miles and 1490 pops. This is where I am at now. Car has 81K on it, new t-belt
and water pump was put in when I bought it.



Temp is perfect, fans working appropriately, car does start a bit dragging in
cold (below 25 degrees). I have noticed throughout all of this the smell of
antifreeze burning off - just thought with work it was burning off engine - no
antifreeze is noted on ground and does not appear to be losing it.



Any thoughts on what else I may need to change? read somewhere to change the
antiknock sensor but I though that had its own code.



Any help will help. Put 25 miles on car since clearing the code and it has not
popped yet. Will up date once it does again.



Thanks for any help

 

 

 

[johnceggleston]

i found this by googleing:

 

http://www.scoobymods.com/showthread.php/thermostat-malfunction-2639.html?s=a6542737f370e31b5d5e8a1795921985&

Edited December 26, 2013 by johnceggleston

[dave_anto364]

Thank you!

[Fairtax4me]

Subaru doesn't monitor the thermostat directly, like mentioned in the linked post above, but opening of the thermostat can be indirectly monitored by looking at changes in coolant temperature.

 

The dealer is right to want to replace the thermostat and the temp sensor, but there could be other causes.

Leaves or dirt stuck in the fins of the radiator, or internal clogging of the radiator.

The heater core is integral with proper operation of the cooling system. If the heater core is partially clogged it will affect opening and closing of the thermostat in cold weather.

 

Replacing sensors is the last thing I would do, unless there is a code for the sensor, or other problems such as failing to switch to closed loop, or hard starting when the engine is warm.