rough idle when cold
#1
Registered User
Thread Starter
Join Date: Feb 2007
Location: NC
Posts: 1,511
Likes: 0
Received 0 Likes
on
0 Posts
rough idle when cold
hey guys the gf has a 2005 corolla 4cylinder with 77k miles on it. when she cranks it up it idles fairly bad but when it warms up its fine.. i am in the process of seafoaming it... any ideas?? do they have a MAF sensor too?? the plugs are irridium supposedly so its not those......
#2
Registered User
Join Date: Apr 2007
Location: Land of Enchantment
Posts: 215
Likes: 0
Received 0 Likes
on
0 Posts
wouldn't be the MAF. that would cause it to idle rough regardless of temperature.
Do you have a check engine light? You should if it's any sensor. That being said, it sounds to me like your coolant temperature sensor.
Do you have a check engine light? You should if it's any sensor. That being said, it sounds to me like your coolant temperature sensor.
#4
Registered User
Join Date: Apr 2007
Location: Land of Enchantment
Posts: 215
Likes: 0
Received 0 Likes
on
0 Posts
yeah, when the coolant temp sensor goes out, the ECU goes into failsafe mode, thinking that the engine is at operating temperature already. So it idles and runs like crap when cold. But when it warms up and is actually at operating temperature, then it runs ok.
Usually this trips a check engine light though.
Usually this trips a check engine light though.
#5
Registered User
Thread Starter
Join Date: Feb 2007
Location: NC
Posts: 1,511
Likes: 0
Received 0 Likes
on
0 Posts
yeah, when the coolant temp sensor goes out, the ECU goes into failsafe mode, thinking that the engine is at operating temperature already. So it idles and runs like crap when cold. But when it warms up and is actually at operating temperature, then it runs ok.
Usually this trips a check engine light though.
Usually this trips a check engine light though.
yeah no light just yet... i wonder if i take it to autozone they can hook it up and see if it reads anything... can it still pick up code even if the light isnt on?
#6
Registered User
Join Date: Apr 2007
Location: Land of Enchantment
Posts: 215
Likes: 0
Received 0 Likes
on
0 Posts
yeah, the ECU stores past codes, even ones that have been corrected. Only way to get rid of them is reset the ECU or clear the codes (which most scanners can do).
that is where i would start, because reading the codes is free and gives you a good place to start checking sensors and what not.
that is where i would start, because reading the codes is free and gives you a good place to start checking sensors and what not.
Trending Topics
Thread
Thread Starter
Forum
Replies
Last Post