Has anyone of the vems users felt that on higher IATs, on cruise the car feels less torquey in the mid range and OFF boost?
I get that impression most of the times when the IATs are higher than 25-30C and im doing small city runs, which makes me think if the problem is the actual engine needing a service or this is a mapping issue.
I am under the impression (and motronic tuners can verify if the want), that motronic makes the mixture a bit richer on higher IATs and leaner on colder IATs in order to avoid the unwanted knock. However when talking about cruise, in both ECUs we are in closed loop, ie motronic keeping lamda =1 and VEMS whatever you wish.
I have my cruise lamda ranging from 1.09 to 1.03 and with the timing i use it seems ideal for up to 25-28C IATs, but whenever i have been in a hotter enviroment, i got the impression that the engine didnt like it being so lean. Even though timing is being trimmed a bit on those IATs to compensate, i cannot tell if it is the mixture being to lean or the timing being too trimmed. My seat dyno is not that clever to tell the difference on changing settings and retesting on the road. I need to test this on a dyno.
Has anyone else experienced anything similar during the summer time? Are you going that lean on the lamda on cruise?
cheers
I get that impression most of the times when the IATs are higher than 25-30C and im doing small city runs, which makes me think if the problem is the actual engine needing a service or this is a mapping issue.
I am under the impression (and motronic tuners can verify if the want), that motronic makes the mixture a bit richer on higher IATs and leaner on colder IATs in order to avoid the unwanted knock. However when talking about cruise, in both ECUs we are in closed loop, ie motronic keeping lamda =1 and VEMS whatever you wish.
I have my cruise lamda ranging from 1.09 to 1.03 and with the timing i use it seems ideal for up to 25-28C IATs, but whenever i have been in a hotter enviroment, i got the impression that the engine didnt like it being so lean. Even though timing is being trimmed a bit on those IATs to compensate, i cannot tell if it is the mixture being to lean or the timing being too trimmed. My seat dyno is not that clever to tell the difference on changing settings and retesting on the road. I need to test this on a dyno.
Has anyone else experienced anything similar during the summer time? Are you going that lean on the lamda on cruise?
cheers
Comment