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Discussion Starter #1
After a few days of trying to get Alfadiag to work with my car i think i have killed her.

I did a faults read just to see what was going on and got a few codes come through. One of these codes was a Lambda sensor and i wanted to clear that as i replaced it the neght before. When i clicked on it to clear it by mistake i cleared all the faults. Now she will not rev up past 4000rpm, when she does she backfires and misfires.

If there is a fault that has not been fixed but cleared should the car not run the same as it did?:(
 

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Clearing fault codes shouldn't have such side-effects. I did that multiple times in the summer when I had problems with the lambda sensor. The fault codes just re-appeared after running the engine for a while.

Maybe your MAF has died? A broken MAF may result in lambda sensor related error codes.
 

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Have you performed an ecu reset? (Will have probably learnt dodgy parameters while receiving bad inputs)
 

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Discussion Starter #4
I did reset the ecu after the faults were cleared. Maybe it ts time i take her to a real mechanic.
 

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Then I would guess it's a broken air flow meter. The ECU had learned to run as well as it can using the erroneous data from MAF, and resetting the ECU cleared these parameters. That's probably why it won't run as it did before the reset. The described symptoms suggest that too.
 
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Firstly what was the make of the lamda sensor, I've read on one of the forums that NGK ones don't work too well on the 156.

If you did kill something then the error code or codes for it should show up again quite quickly.

It may well be the MAF as suggested already but I think the fuel trims would have been reset along with the ecu and will take a little time to correct themselves.

I'm sure David C or someone else ITK will correct me if I'm waffling.
 

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Discussion Starter #7
Does the MAF give a fault code?
 

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Does the MAF give a fault code?
Usually, a MAF that has started giving faulty data but is not completely dead gives lambda-related error codes. The resulting wrong fuel mixture may also damage the lambda sensor in the long run.

If you are using Alfadiag, you might want to check the air flow meter readings during full acceleration for example.

On the other hand, if you could borrow a working MAF from a friend, it would be easy to check. It's a 10-minute job to change.
 

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Discussion Starter #10
Going to have a key cut and programmed tomorrow morning at Lombarda so i can pick up a new MAF there. Cheers guys, will let you know if it works.
 
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