does engine temperture reading effect engine performance
07-12-2005, 02:21 PM
#1
does engine temperture reading effect engine performance does the temputure of the engine by the temp sensor change engine performance?
So what if the temperture was always the same and only the reading was changed say 180degree reading was changed to read 200degrees besides the cooling fans turn on points does it do anything. if so What does it do?
Are there certain temp points at which it does different things to the engine as far as any performance differences such as air/fuel ratio etc.? example: at 80 it has a program for warmup and at 200 it is nomal and at 250 it has knock retard.
or does it change throughout the temp range?
or does it have no effect?
So what if the temperture was always the same and only the reading was changed say 180degree reading was changed to read 200degrees besides the cooling fans turn on points does it do anything. if so What does it do?
Are there certain temp points at which it does different things to the engine as far as any performance differences such as air/fuel ratio etc.? example: at 80 it has a program for warmup and at 200 it is nomal and at 250 it has knock retard.
or does it change throughout the temp range?
or does it have no effect?
07-12-2005, 02:37 PM
#2
The engine temp has a lot to do with different aspect of the computer tune. It alters air/fueling, timing, retard and even shift points for A4s. basically, it is a critical value for performance. I would not alter the engine temp sendors values.
07-12-2005, 03:48 PM
#4
TECH Senior Member
depends on wher eit is in the cold/hot range... cold AFR is generally richer, hot it also goes richer
hot timing is generally pulled
shift points are changed if the temp is higher than x degrees in which case it uses the hot shift tables....
If you're contemplating tricking the ECT sensor to try to pull timing or add fuel I wouldn't suggest doing so... there are alot of other tables in the PCM that ECT (Engine Coolant Temp) has an effect on ... and ECT is one of those sensors that you want to read accurate at the PCM
hot timing is generally pulled
shift points are changed if the temp is higher than x degrees in which case it uses the hot shift tables....
If you're contemplating tricking the ECT sensor to try to pull timing or add fuel I wouldn't suggest doing so... there are alot of other tables in the PCM that ECT (Engine Coolant Temp) has an effect on ... and ECT is one of those sensors that you want to read accurate at the PCM
07-12-2005, 04:05 PM
#5
Originally Posted by horist
depends on wher eit is in the cold/hot range... cold AFR is generally richer, hot it also goes richer
hot timing is generally pulled
shift points are changed if the temp is higher than x degrees in which case it uses the hot shift tables....
If you're contemplating tricking the ECT sensor to try to pull timing or add fuel I wouldn't suggest doing so... there are alot of other tables in the PCM that ECT (Engine Coolant Temp) has an effect on ... and ECT is one of those sensors that you want to read accurate at the PCM
hot timing is generally pulled
shift points are changed if the temp is higher than x degrees in which case it uses the hot shift tables....
If you're contemplating tricking the ECT sensor to try to pull timing or add fuel I wouldn't suggest doing so... there are alot of other tables in the PCM that ECT (Engine Coolant Temp) has an effect on ... and ECT is one of those sensors that you want to read accurate at the PCM
so this is what I understand so far
shift points: stay the same until a temp x which is when it goes to hot shift tables.
timing: the hotter the less amount of timing. are there certain temps that things change or increments?
Air/Fuel: rich when cold then gets leaner when at normal temps then rich when hot. is this also at certain temps or in invrements?
is this all that is affected?
