Is there an explanation as to why the check engine light does not immediately come back on when the same computer has been pulled out and returned to service some days later?

If it was the 'self adaptation' feature at its limit that caused the CE light, it takes a number of 'trips' to change to what it was. A 'trip' is defined as; 5 mins of engine operation; speed greater than 5mph and tach greater than 500rpm.

So starting the car and shutting it off is not considered as a trip. Also running the car for 90 mins is considered just one trip (assuming the other parameters were satisfied).

If an injector is bad, i would think you surely would notice it! The car should idle roughly.

So it does takes some time for this to happen but you seemed to indicate that you have satisfied the 'trip' requirement and light has not come back. Don't know why!

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Regards . . . . JimF
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'94 S500 Cpe

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