Omega Owners Forum
Chat Area => General Discussion Area => Topic started by: JiMbOb789 on 16 May 2008, 12:28:44
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hello,
what is limp mode and how were you ment to fix it?
I had it on my first omega and i took it to a mechanic and he didnt know what was wrong with it so i gave it back to the car showroom for another one.
Anyone help?
Thanks
Jamie
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To put it simply.
If the ECU detects a sensor failure then it might not be able to calculate a safe/efficient fuel dosing or spark timing value.
Because of this, there are certain sensor failures which cause the ECU to adopt limp mode where by, rather than take values from the failed sensor, a pre-programmed set of default values are assumed.
This gives different results dependent on what sensor is at fault but, often also results in a 4500rpm limit being imposed so as to safeguard the engine and ancillaries.
So, its exactly what it means, it keeps the engine running on default (non-ideal) values in order to be able to limp home or to a garage for repair.
-
To put it simply.
If the ECU detects a sensor failure then it might not be able to calculate a safe/efficient fuel dosing or spark timing value.
Because of this, there are certain sensor failures which cause the ECU to adopt limp mode where by, rather than take values from the failed sensor, a pre-programmed set of default values are assumed.
This gives different results dependent on what sensor is at fault but, often also results in a 4500rpm limit being imposed so as to safeguard the engine and ancillaries.
So, its exactly what it means, it keeps the engine running on default (non-ideal) values in order to be able to limp home or to a garage for repair.
oh i see, thanks mate.
So to fix it, you would have to find and replace the broken sensor?
Has anyone on here ever had it?
Thanks again,
Jamie
-
To put it simply.
If the ECU detects a sensor failure then it might not be able to calculate a safe/efficient fuel dosing or spark timing value.
Because of this, there are certain sensor failures which cause the ECU to adopt limp mode where by, rather than take values from the failed sensor, a pre-programmed set of default values are assumed.
This gives different results dependent on what sensor is at fault but, often also results in a 4500rpm limit being imposed so as to safeguard the engine and ancillaries.
So, its exactly what it means, it keeps the engine running on default (non-ideal) values in order to be able to limp home or to a garage for repair.
oh i see, thanks mate.
So to fix it, you would have to find and replace the broken sensor?
Has anyone on here ever had it?
Thanks again,
Jamie
More common on the 4 pots as when for example, the cam sensor fails, the 4500rpm limit is imposed.
On the V6, its less common unless you bugger up a knock sensor lead in whcih case you get much reduced power output and a rev limit.
But yes, fix the faulty sensor and all will be restored to normal.
-
To put it simply.
If the ECU detects a sensor failure then it might not be able to calculate a safe/efficient fuel dosing or spark timing value.
Because of this, there are certain sensor failures which cause the ECU to adopt limp mode where by, rather than take values from the failed sensor, a pre-programmed set of default values are assumed.
This gives different results dependent on what sensor is at fault but, often also results in a 4500rpm limit being imposed so as to safeguard the engine and ancillaries.
So, its exactly what it means, it keeps the engine running on default (non-ideal) values in order to be able to limp home or to a garage for repair.
oh i see, thanks mate.
So to fix it, you would have to find and replace the broken sensor?
Has anyone on here ever had it?
Thanks again,
Jamie
Frequently!
Touch wood, never had it on MV6 - only sensor failure I had on that was the one where there is no 'default' values, hence no limp, ie the cranksensor.