'88 S4 Dies unexpectedly; otherwise, runs perfectly
#61
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You appear to have a false understanding of the knock sensor operation. If you have a knock sensor down [or the Hall sensor] the car will run OK but it will do so with 6 degrees of advance removed from the mapping across the board and that will lose a chunk of power/torque.
#62
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Hi Fred. Yes! I am happy that the car runs, no doubt. Just not intellectually satisfied since the presumed fault in the LH was not definitevely identified nor replicated.
I understand how the knock sensors work. But since the sensors' condition has been the same (presumably not working) since I acquired the car 3 months ago and not having owned another 928 I have no frame of reference to say whether I am missing some power if the sensors retarding the timing because they are malfunctioning.
I understand how the knock sensors work. But since the sensors' condition has been the same (presumably not working) since I acquired the car 3 months ago and not having owned another 928 I have no frame of reference to say whether I am missing some power if the sensors retarding the timing because they are malfunctioning.
The LH is something of a strange animal in that there are some predictable failure modes and some seemingly strange ones. At least you now know that you have eliminated a common [inevitable] problem and you will have piece of mind for a while plus all the support John normally gives with his rebuilt units that have an excellent reputation.
I had one of my knock sensor connectors fall apart and still managed to make it work for quite a few years. What one needs is access to something that can tell if they are working [or not]. Guessing is what it is- guesswork.
Just remember these cars are an ongoing work- never really finished and invariably something else will be close to failure as one fixes the latest problem. Owners have a choice- either go through the job lot in one big hit or be prepared to fix things as and when. The list of possibilities is quite extensive, the list of probabilities a good bit less. I have the probabilities covered but the possibilities I deal with as and when.
#63
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Luis,
Why not drop Louis a note and ask that when they rebuild your old unit, they let you know what they found specifically wrong for your own intellectual gratification? John and Louis can only say no if it's too much to ask.
Louis put the LH in one of his cars and it ran fine (this time). I'm sure that some kind of electronic "jig" tells JDS what part has actually gone haywire before he rebuilds it. He might be willing to share that info with you.
Why not drop Louis a note and ask that when they rebuild your old unit, they let you know what they found specifically wrong for your own intellectual gratification? John and Louis can only say no if it's too much to ask.
Louis put the LH in one of his cars and it ran fine (this time). I'm sure that some kind of electronic "jig" tells JDS what part has actually gone haywire before he rebuilds it. He might be willing to share that info with you.
#64
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Luis,
Why not drop Louis a note and ask that when they rebuild your old unit, they let you know what they found specifically wrong for your own intellectual gratification? John and Louis can only say no if it's too much to ask.
Louis put the LH in one of his cars and it ran fine (this time). I'm sure that some kind of electronic "jig" tells JDS what part has actually gone haywire before he rebuilds it. He might be willing to share that info with you.
Why not drop Louis a note and ask that when they rebuild your old unit, they let you know what they found specifically wrong for your own intellectual gratification? John and Louis can only say no if it's too much to ask.
Louis put the LH in one of his cars and it ran fine (this time). I'm sure that some kind of electronic "jig" tells JDS what part has actually gone haywire before he rebuilds it. He might be willing to share that info with you.