-- EDIT: The actual rebuild starts on post 17.
Below is some background.
Okay, so in some other threads, I (we) have come to the conclusion that my fuel distributor is bad, dumping fuel into cylinder one.
1) Black, carbon fouled plug for 1 (all other plugs clean).
2) Missing at idle is not as bad after an extended freeway run (indicating the freeway run helped clear fouling). Missing at idle is worse after stop-and-go traffic, indicating that low RPMs increase fouling.
3) Missing is mainly at idle and RPM under 2000. At 2500+ and under load (freeway) car is super smooth - this indicates that cylinder 1 is now getting closer to the correct mixture, as all the other cylinders are now using much more fuel at high RPM and under load (in a sense, cylinder 1 then "catches up" and preforms closer to the other cylinders).
4) Injectors are all new - as you may recall I originally replaced injector 1 thinking it was leaking and dumping too much fuel into cyl 1 - obviously the injector *may* have been damaged or weak, but the real culprit here is the fuel distributor.
5) There has been occasional fouling appearance on the plugs for cylinders 2 and 5 - both right next to 1 on the fuel distributor - this indicates that the diaphragm failure may intermittently be spreading to cylinders 2 or 5.
I attempted to contact CIS Flowtech, as well as SpecialTAuto to inquire as to current stock for my car, but neither got back to me in a timely way. In the meantime I found several rebuild kits on Ebay. One located in Florida, and the other in San Francisco. Both promised Viton o-rings and new technology for the diaphragm that is said to be impervious to ethanol. I went with the American Precision Machinery version (CIS-Jetronic on ebay) as they were closer and I'd get it sooner, though it was slightly more expensive.
cis-jetronic | eBay
I received it today. $94 and free shipping. Kind of expensive, but certainly less than a remanufactured unit. And I get the joy of doing it myself.
The replacement diaphragm is very thin. It is a nylon mesh supporting a rubber type of material (viton?? Nitril?) The kit also comes with a complete set of viton Orings.
My plan of attack is to do a "minimal disassembly" - in particular I want to avoid even toughing the individual adjustment screws as I don't have access to the special Bosch tool for aligning the flow on each port. I also will be keeping very careful sorting of the parts, so that all springs and valves go exactly back to the same port they came from.
I will not be doing an ultrasonic bath, but I will be spraying and gently cleaning all the little ports in the unit. With the amount of fuel system cleaner that has gone though my car in the last two months, I actually expect the interior to be fairly clean.
The single main pressure regulator is adjusted by means of shims, so I will be replacing those o-rings. As this car is LAMBDA equipped, I am running on the assumption that the lambda system will take up any slack where I may be off in adjustment.
Except of course for the individual channels, and as I said I intend to leave those alone.
I'll be tackling this tonight or tomorrow, and will of course provide further images and discussion.
Here are some images of the rebuild kit. Note on the second image, the diaphragm is really a paper-thin piece. I'm not sure how the material will compare in stretch to the original, or how that may affect system pressure or differential channel output - but we're about to find out!