Area Representative Tin Man Posted January 4, 2002 Area Representative Share Posted January 4, 2002 I have just fitted a 4:2:1 race exhaust to my 1.8 s/s k-series with no cat. Do I need to fit the lambda probe, or can I just fit the blanking plug. Will it make any difference without the cat? Thank you Link to comment Share on other sites More sharing options...
oilyhands Posted January 4, 2002 Share Posted January 4, 2002 The Lambda sensor is there only to allow the ECU to keep the Cat happy and for mapping purposes, if you havent fitted the Cat then there is no point in fitting the Lambda.. In operation during closed loop running the ECU uses the Lamda input to cycle the AF ratio either side of stoichiometric which keeps the CAT up to temperature and enables it to do its job. During mapping the Lambda sensor input is used to establish where the mixture is WRT stoi. Removing the Cat may make a small difference to performance. Oily Link to comment Share on other sites More sharing options...
sjwb Posted January 5, 2002 Share Posted January 5, 2002 Explanation: Lambda sensor (O2 sensor) (Oxygen Sensor) exists for the following and is situated above the catalyst in the Caterham scenario. A comparison between the level of oxygen in the exhasut gas to that in the atmosphere produces an output (electrical) signal. The signal is used by the engine 'closed loop' fuel strategy to make FUELLING corrections and so CONTROL overall emission levels. The fuelling correction is achieved by varying injector pulse duration. Nothing else to it, no mystery, simply this. Where there are two sensors - one upstream and one downstream of the catalyst, the comparison of upstream and downstream signals allows determination of catalyst conversion efficiency. Steve B Link to comment Share on other sites More sharing options...
Tony Martyr Posted January 5, 2002 Share Posted January 5, 2002 As both the previous replies state, you don't NEED the Lambda sensor if you have no Cat. But if you still have an ecu that is running on the original closed loop map it will be expecting the feed back form the sensor. Some systems will judge no signal as a fault condition and revert to a emergency map. If you have an ecu that does not have closed loop control of exhaust oxygen content, like the dta, it will not equire the sensor during normal running. BUT it should be used during mapping so that the idle gas test for MOT can be adjusted. I left mine in place and only electrically plug it in once a year for a mapping adjustment Link to comment Share on other sites More sharing options...
Area Representative Tin Man Posted January 6, 2002 Author Area Representative Share Posted January 6, 2002 Many thank`s for the help.I have the std s/s ecu so i will fit the lambda sensor. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now