Lambda sensor

nowayout1

Hey guys recently got my mechanic to change the lambda sensor on my 04 carisma after emissions where sky high on the NCT & goes on saturday to the NCT. But he tested it and gave me to results from the new one which is a lot lower than when it was tested. But one thing is up on the failed sheet it says Lamda should be on 0.97-1.03% @ 2750 RPM but on his results its showing 1.106% at the same RPM. He said the lambda will reset itself and to just bring it on long drives each evening until the test so it can be broken in. Is this correct or should the code on the computer be reset since the EML is still on and bring that reading down to where it should be?

Cee-Jay-Cee

Disconnect the negative terminal on the battery for ten minutes, reconnect it and start the car but don't drive or Rev it. Let the car idle for 10-15 minutes until up to full temperature then switch engine off and on again and go for a drive. The ECU is now reset. If the engine light stats on then get someone to reset it, if it comes back on again get the code as its but the lambda that's causing it.

Make sure the engine is fully up to temperature before your NCT, take it for a 15-20 drive immediately before the test.

If you haven't already done so, change the oil, filter and spark plugs before the test too. You should pass no problem.

nowayout1

will reset the ECU tomorrow then & bring it on a drive. grand I'll someone to reset the engine light. I indeed to drive it before going for the test. You recon to drink it in 3rd or 4th gear hitting 3,000rpm to get the sensor working good? I got it serviced in November you think the oil should be changed?

B00056718

The light should be self resetting after a few engine start ups, shouldn't it be?

Unless the fault is still present off course.

blackbox

nowayout1 wrote: »

Hey guys recently got my mechanic to change the lambda sensor on my 04 carisma after emissions where sky high on the NCT & goes on saturday to the NCT. But he tested it and gave me to results from the new one which is a lot lower than when it was tested. But one thing is up on the failed sheet it says Lamda should be on 0.97-1.03% @ 2750 RPM but on his results its showing 1.106% at the same RPM. He said the lambda will reset itself and to just bring it on long drives each evening until the test so it can be broken in. Is this correct or should the code on the computer be reset since the EML is still on and bring that reading down to where it should be?

What was the lambda reading on the NCT fail sheet?
I'm guessing a 2004 will have 2 or more lambda probes. Do you know which was replaced?

nowayout1

@blackbox I've attached the fail sheet, yeh it was the one on the manifold that was changed. It was changed from one that was split & connected using connectors to one that has a block connection.

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nowayout1

@cee-jay-cee just done what you said to do & say the ECU has resetted itself & no light yeh letting it heat up for 25 mins & turn it off & back on, then bring it on a spin. Left the negative cable off the battery for 20 mins. I'll get my mechanic to hook it up to his computer again on Friday to see if this has helped. Also I've everything turned off in the car ie heaters, fans, radio interior light to help the ECU.

blackbox

Fail sheet definitely points to lambda probe failure - unless mixture is so bad for some other reason that system could not compensate.

nowayout1

@blackbox this was the emissions test done by my mechanic on Monday after replacing it on Thursday. Hydro carbons & CO2 are what they should but lambda still not down as low as it should.

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dieselbug

The o2 content is too high. Ask your mechanic to check the exhaust for leaks and look to see if the lambda sensor is acting as it should.

nowayout1

Thanks guys for all of your comments, the car passed the NCT retest