Error Code Resetting

[warthog]

Hi all,

I'm sure that this question has been possed in the past but can find no reference to it on the search.

I have error code 1-4-3 and the Lambda light on. The code refers to the front knock sensor signal.

I have tried to reset the code to check if it was a spurious error but with no success.

The Haynes manual suggests reading all the codes (done) then holding the button down for 5 secs. Wait for the light to come on then hold button down for another 5 secs. This didn't work. Neither did disconnecting the battery for about 1/4 hour.

To reset by disconnecting the battery (as per Bay 13 info), do I have to have the flying lead connected to pin A2?

Any help gratefully received.

Cheers

Warthog

[Chris_Rogers]

From my experience, to reset codes you need to give the second 5 sec push of the button before the LED goes out, you have to be quick.
You may also find that you have to press for a bit longer than 5 secs.
When you're successful you will hear the fuel pump run for about 6 secs.

Hope that helps.

[warthog]

Chris,

Many thanks. I got it sorted earlier by trial and error (excuse the pun!)

The secret is to not turn the ignition off and on again between reading the codes and resetting the error.

So far the error has not re-occured so I'm hopeful that it was just a glitch.

Regards

Warthog

Dear Mr Warthog,

I too have an eror code 143 which refuses to go even when reset (so I guess the front knock sensor really is inoperative or missing ? !)

Have you noticed any change in fuel consumption with/without the error ? I am hoping that my faulty knock sensor is the cause of my abysmal fuel consumption ! I expect sub-20 when I drive it :-) but I am currently taking a "rest" from driving (due to unmarked black BMW on M40 ...) so my wife has been doing all the driving and we're still getting around 20 mpg !

Any thoughts on low fuel consumption would be most welcome. Could it be the infamous perishing rubber elbows ?

Many thanks in advance

Steve

[warthog]

Steve,

If the code keeps coming back following a reset, then I would think there would be a pretty good chance that there is a definite problem! Without a full set of telemetry from the engine sensors, the ECU will adjust its mapping so that the engine continues to run allbeit at a less than optimal level. I would expect that in this state, the fuel consumption would be greater than normal. I would also strongly advise that the sensor error is corrected asap as one doesn't know what damage is being done by continued running. It would surely be cheaper to sort a knock sensor out than a valve or piston!

Whilst my front knock sensor was showing an error, the fuel consumption actually improved, but I put that down to the care with which I drove. I needed to drive about 130 miles in this state before I could sort the problem, so I was done with extreme caution. I was getting over 30mpg.

Around town and fast country roads I too average 20-24 mpg. This creaps closer to 30 at constant (slow/legal/boring) motorway speeds!

I believe that if the rubber elbows go, then you get the error code ofr incorrect mixture.

Cheers

Brian

Evening Brian,

Thanks for reply.

I have been asking at work (Ricardo) on this ...

The timing should revert to base map if no signal from knock sensor - this should be "safe" ie no risk of detonation (pinking). While this could push the engine off theoretical peak efficiency, the effect should be small and may be "adjsuted" for by boost pressure and fuelling to maintain correct combustion. I have never heard any pinking even under high load :-)

What worries me is that I phoned a main dealer a while ago for a quote on a new knock sensor and they quoted £80+ but mentioned that he'd never sold one in 10+ years of running the stores ! Looking at a typical unit at work it's pretty robust with no moving parts so its hard to see what can go wrong ! I now suspect a wiring fault and will investigate chaffed wires and dodgy connectors at the weekend ... now do I trust my inlet manifold gasket will come off cleanly and be re-usable or should I order a new one first ... ?

Best regards

Steve