| With apologies for the non-geeks on the board... I recently chased a thread to a picture someone posted of the internals of a failed injector showing considerable corrosion of the winding. (anyone know this link offhand?) I'd be very interested to see a picture of the winding inside a new style injector as I have a suspicion that the "fix" Nissan (or Bosch or whoever makes the injector) engineers applied would offer a valuable insight to the problem and its solution. I'm not convinced at present that the circuit bypass trick will be effective. This is a matter of semantics for some, but technically "electrolysis" probably isn't the best description for the process of winding failure. [Electrolysis is the process of splitting a compound into ions in the presence of an applied potential.] From a chemical perspective the question to answer is: what happened to the copper lost from the windings? If this is an electrochemical process the copper oxidized from the winding needs to migrate through an electrolyte and be deposited at some cathode. There are two problems with this scenario, first is that the injector is supposed to be electrically isolated since it sits in two nonconductive rubber o-rings, and the second is that gasoline is a very poor electolyte and copper ion is poorly soluble in these nonpolar solvents (hence there would be little chance for the oxidized copper ion to be transported through the electrolyte to complete the electrolytic circuit). Bottom line, if there is not a complete electrochemical cell/circuit - there won't be a corrosion of the windings. As an aside, if an injector is NOT properly isolated from the plenum (metal filing, moisture, etc bridging the injector body to ground) I'd expect poor injector performance and premature winding failure. If electrolysis is involved, it is most likely in the splitting of the ethanol into ethoxide anion and hydrogen cation (acid). This situation could indeed lead to a rapid deterioration of the windings but also begs two obvious questions... Why doesn't the corrosion issue happen on other (chevy, honda, toyota,...) injectors, and why haven't the refinery engineers designed an additive package to scavange these electrolysis products? Corroding a few 300ZX injectors is one thing, but killing every injector in production vehicles is a sure recipe for a costly class action suit... Which brings me back to my first question, what is unique about the early 300TT injector design that predisposes it to failure when exposed to ethanol? Anyone have design information on new injector windings? Are these wires coated or a different alloy? The field effect generated by the voltage pulse which operates the injector doesn't require direct contact of the fuel with the winding surface - the obvious fix is to isolate them with a coating the same way rebar is now coated for bridge decks...
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