rough idle, my plans.. anything else i should do?
#41
#43
if its jumping, more than one cyl. at a time. if not, only one.
(and thats what the ecu and the smaller contact do, only differently, right? keep it from jumping?)
#44
Brian is right there. Compare a 44 gallon drum rolling on the garage floor and a 1" tube socket rolling on the same floor - if each were to complete a single rotation on the floor, you will find the 44 gallon drum covered a distance of about 100" while the socket would only have covered a distance of 2" ................. the same concept applies to the diameter of dis cap and rotor length.
Additionally - with ECU designs controlling advance (from a pre determined static position) , you will generally find that the ECU can affect a much wider range of optimized timing values depending on ambient and engine load conditions (when compared to what the vacuum and centrifugal advance on a mechanical advance system can manage) requiring the ability to still reliably feed the spark to the correct cylinder - ie - you have to be able to ensure correct spark destination for 45 degrees variance with the ECU rather than just 30 degrees with a mechanical setup .................... the limiting factor here is the distance a spark can travel in air, and you have to ensure you don't make that rotor tip too long causing the spark to possibly jump to the wrong cylinder
Additionally - with ECU designs controlling advance (from a pre determined static position) , you will generally find that the ECU can affect a much wider range of optimized timing values depending on ambient and engine load conditions (when compared to what the vacuum and centrifugal advance on a mechanical advance system can manage) requiring the ability to still reliably feed the spark to the correct cylinder - ie - you have to be able to ensure correct spark destination for 45 degrees variance with the ECU rather than just 30 degrees with a mechanical setup .................... the limiting factor here is the distance a spark can travel in air, and you have to ensure you don't make that rotor tip too long causing the spark to possibly jump to the wrong cylinder
#46
[QUOTE=MaximaN00b;6293485]well, id say my KS is fine, and bypassing is maybe not the best idea.. least for me!
my car acted strangely, rather than better.. so obvious sign my KS was fine.. so i took the bypass off.QUOTE...
if you did ks bypass right\use the right resistor it would run the SAME IFwere bypassed or you hooked the ks back up normal because when bypassed The resistor always sends back the correct value as it would when you un bypass it with a working ks ,right you guys.?
anyone know if the resistor has specific polarity or can be hooked up backwards?is that what the gold ring painted on the resistor is for?
my car acted strangely, rather than better.. so obvious sign my KS was fine.. so i took the bypass off.QUOTE...
if you did ks bypass right\use the right resistor it would run the SAME IFwere bypassed or you hooked the ks back up normal because when bypassed The resistor always sends back the correct value as it would when you un bypass it with a working ks ,right you guys.?
anyone know if the resistor has specific polarity or can be hooked up backwards?is that what the gold ring painted on the resistor is for?
#47
The gold ring indicates the actual resistance of the resistor is within 5% of the nominal value denoted by the other 3 rings on the body of the resistor.
For the record only:
The resistor bypass serves 2 purposes:
1. It fools the ECU into thinking that a working KS is present and
2. It prevents spurious signals (EMI etc etc) appearing on the KS cables running to the ECU from falsely triggering the ECU into "delayed timing mode" ....................
and in both cases the resistor is not doing anything at all other than preventing a rogue pulse falsely triggering the ECU (or even triggering the ECU at all) - the resistor is not "sending" or "transmitting" any usable info to the ECU re knock. The KS is a piezo crystal that generates a voltage as a result of mechanical deformation, and its response characteristics has been chosen to be close to that found to be present when knock occurs on an engine - ie - it outputs a usable/measurable voltage spike/signal only when the crystal gets excited by the energy content of the "knock vibrations" when they occur - the ECU responds to those voltage spikes ............... and not resistance values. Implication - you can use probably any resistance value between 50K and 1M and the KS bypass experiment will result in exactly the same outcome - ie - the ECU being prevented from affecting timing due to a KS terminal signal
For the record only:
The resistor bypass serves 2 purposes:
1. It fools the ECU into thinking that a working KS is present and
2. It prevents spurious signals (EMI etc etc) appearing on the KS cables running to the ECU from falsely triggering the ECU into "delayed timing mode" ....................
and in both cases the resistor is not doing anything at all other than preventing a rogue pulse falsely triggering the ECU (or even triggering the ECU at all) - the resistor is not "sending" or "transmitting" any usable info to the ECU re knock. The KS is a piezo crystal that generates a voltage as a result of mechanical deformation, and its response characteristics has been chosen to be close to that found to be present when knock occurs on an engine - ie - it outputs a usable/measurable voltage spike/signal only when the crystal gets excited by the energy content of the "knock vibrations" when they occur - the ECU responds to those voltage spikes ............... and not resistance values. Implication - you can use probably any resistance value between 50K and 1M and the KS bypass experiment will result in exactly the same outcome - ie - the ECU being prevented from affecting timing due to a KS terminal signal
#48
Resistor has no 'polarity' (diode has). A said, gold ring is the mfg tolerance code, other colors denote the resistance value.
I have read that the stealerships open the KS and re-tension it, use it on 'your' car and of course charge for a new KS.... Dunno if this is true, but possibly possible as the ALU piezo is so soft metal.
I have read that the stealerships open the KS and re-tension it, use it on 'your' car and of course charge for a new KS.... Dunno if this is true, but possibly possible as the ALU piezo is so soft metal.
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