Me again . . lol OK here's the deal . . . Work on Z, Z goes well . . . Z goes home . . Z goes sleep as do I . . . . Z is f'ed again the next day. This doesnt bother me too much, I like classic motorcycles and riding one of them is much like owning a Z . . . lol The main problem seems to be the following . . . one of the connectors that sends the voltage to the injectors to allow for pulse is reading 12 volts no matter what, . . . . Not pulsing 12 volts . . . 12 volts constant. This would mean that the injector is open ALL the time. Even when the car is off. However, even though the car seem to be running rich (and apparently on 5 cylinders) the richness is not coming from the culprit injector connector always having voltage. It seems that the injector itself is not even working so the fact that the connector is at 12 volts constantly is not making it rich. We tested all the other Z's in the shop, none of them have 12 volts constant to the injector connector even when the car is off. Plenum is being pulled tomorrow, all pipes etc being re-done. New o2 sensors and pcv's going in. EGR delete being completed (it was half done and left that way) injectors, o-rings . . . etc etc. right down to all the pipe and electrical clamps. If it can be replaced it WILL be replaced. The only thing that I can think of for the connector voltage is that it is either being fed 12 volts by the battery from a short somewhere . . . . or there is a ghost in the engine determined to make me insane. . . lol. Has anyone encountered this problem and have a solution? Or Can a whole engine harness be purchased new or aftermarket? Thanks . . . :bow2:
You realise that the ECU switches the Injector earth side to fire the injector. The injectors have 12v on them all the time on one side.
Actually, the injectors do have a constant 12V feed to the larger wire regardless of ign key position. This is stock from the factory. Just about every other electrical circuit in the zed is set up this way. The ECU sends an earth pulse to fire off the injector. You can't measure this without a special instrument (noid light?). The only bush-mechanic way to see if the injector is firing is the old screwdriver to the ear method whilst engine running or remove the CAS with wiring plug connected and slowly twist the rotor. I'd say you still have a connectivity problem at the injector. the female pins from the wiring loom can get pretty gummed up and even though they visually look OK can still have a film of crap which affects the earth pulse. I'd replace the wiring plugs if you are doing a plenum pull anyway. Ensure you file the injector terminals so they come up bright. As far as the other zeds that didn't have it, all I can say is maybe they have all had the mod where you change the 12V + source from constant12V to ignition only 12V.
but the five other injectors in the car don't have 12 volts constant just this one ??? He has changed all the injector plugs also??? I Have a noid light and will see what happens today
The constant 12v is only on one connector, we tested all of the others. The front left cylinder (#1?) has the only injector connector that does it. 12v constant even when the car is off and the key is out. All of the other injectors on my car do not do this . . . The only other thing I can think of is another incomplete mod? or is the 12v mod one thing and across the board? (i.e: if its done to one its done to all) Thanks
The + feed is constantly live, so if you test voltage between this and earth then you'll see a 12v all the time. If your getting 12v across the connector then something is wrong. I had this recently from a shorted loom which fried an injector driver. Here's a test, unplug the ecu and test for continuity with a multimeter across the injector plug, if you get any reading at all you've got a damaged loom as there should be none.
thanks for this new test, I will do this tomorrow first thing. The thing that has us stumped is that this is only on one connector. ALL of the others do not do it and none of the others on any of the other Zed's we have there do it. The problem is between the + and - of the injector connector from the harness but we have yet to also test the injector itself, we are going to take the whole rail out and wet test all injectors on it. Whole new harnesses are available for around $500 complete OEM. I am going to buy one of these anyway because my harness cable looks like it has been backed out by a homeless guy whom was given curry the night before. I am thinking that you are right, wiring HAS to be the man culprit and it is all pretty bad. It is the only reason I can see it being good / bad / good so often. Connections vibrating and wriggling free / loose / making contact again / etc. Most other things mechanical have been tested and eliminated and all major engine parts are fine. Peace and thanks for the help, will report back once the problem has been found and solved so that others have further reference if they have a similar problem.
Did test, no continuity . . good because that means that the loom isnt shorting or broken. Bad because it only does it with my ECU present. Other ECU's in the car did not do it so it is meaning that I have a friend ECU (or at least the injector controling part of the ECU. dont know what to do except buy another one? Peace
