jray1942

Yellow Fever, 90 degrees is close enough for me too! (ref Post #21) Thanks

The Water Temperature Switch on my '75 280Z checks no continuity at any state, hot or cold and needs replaced. The only one I find is at the Z store for a 74 260Z. Will it work??

Not very hard was it? I try to keep things simple in this complicated era. I tried your suggestion about the unit to no avail as I couldn't hear anything but I reinstalled it as I think I may have multiple issues. I just got this car and has been sitting for years. It's in fairly good condition for a 34 year old car. The PO has had it since 1976! and it has 48,000 actual miles. I spent the first 2 weeks getting the dash lights to work without blowing a fuse.(12 to be exact!) Finally discovered a very bad dealer wiring job that had someone connect what they used to call floating ground to a earth or body ground under the center console, the last place I looked! Here's the overall engine problem. It will start, very hard, and would idle fairly evenly. It would not take a throttle at all and would just stall out. I eventually got around to checking the timing and someone had set it -20 degrees! But when I placed it back to 7.0 degrees(0degrees on timing mark) it now barely idles at all, a stumbling 500 rpm, and I cannot set the idle screw anywhere that has any real effect. I of course still wont take any throttle. Here's what I have done: All injectors are working. I took all of them out and inspected and cleaned them. They are at least working mechanically as I used the audio 'click' test the few times I can keep the engine idling. I have replaced all the fuel hoses by the way. I took off the air flow meter and checked the values as indicated by FSM and checked normal. Pulled off and checked pressure regulator. cleaned it and seems to be ok but of course that's not conclusive. It at least was not plugged up. By the way, I screwed up! First time! (this week!). I wanted a check on the AIR REGULATOR stead of the cold start valve. Can't read schematics anymore either. So it could still be an issue as the valve was hung up when I first took it off. I sprayed it with some carb cleaner inside and it broke loose and then began to spring back into place. The cold start valve was also removed, inspected, cleaned and tested with a 12v source and did pass the 'click' test. So that's where I'm at right now. Drawing on your obvious experience what would you do next? I'm thinking of pulling the throttle body next. Any help is appreciated. By the way, I used took work for some racing teams in the old CART, Champ Car, Indy Car and Atlantic's series and pulled several race transporters thru San Bernardino on the way to either Fontana, The old Ontario, and California Speedway. JR

sblake01 Thanks for the info. and your effort to check it out. I kinda thought that there had to be pressure of some sort after reading the FSM test for the unit but was trying to find an less complicated way. I'll try it again and get it closer to my ear. (I'm old you know!) Thanks again for the input.

I have a '75 280Z w/ L28 engine. I removed the unit from manifold. Attached a 12v source across connectors. There was no 'click' heard. Valve can be actuated manually aganist internal spring an seems to be moving freely. Is the a correct test other than the complicated one used by the FSM?

Not that easy. I just obtained this car for restoration. This issue bugged the previous owner and was one of the reasons I got it 'cheap'. He had jerked out the dimmer control thinking it was bad but it isn't an issue as it only effects the current in the lamp. I have reversed the wire to the dimmer just in case he had done that very thing but it should'nt matter as the only effect is to reverse the direction of illumination control. I'm going to lift the body ground wire today to see if that has any effect on my short with the G/W wire to see if I'm getting a false reading. Additional, When I check the power side (12v) at the fuse without the light switch I get about 50 ohms which is about right. When the lite switch is placed in either park or headlights, this same point shorts to ground. Thanks for any help, and I will again check for reversed connections which the previous owner may well have done.

I'm having a problem with my dash light circuit on my 1975 280Z. When ever any lights are turned on the 20amp fuse for the Lighting/dash lights burns out. All the running lights will work if I disconnect the dimmer resistor. Using the FSM ( Page BE22)I have done the following steps: Checked all lamps in circuit (Running lights as well as dash lights) for corrosion and have checked that all lamps are good by pulling out all gauges and testing them with an outside 12 volt source. Checked the dimmer control and registers good with 10 ohms at full resistance. Have checked the fuse block front and rear. All good. I have disconnected all the instruments from the instrument harness and completely isolated the circuit by disconnecting C-2,C-4, C-6, and combo switch. All 5 instruments are unplugged from harness. That would indicate that there is no connection with the Green/white power line. It measures dead short to body ground! 2 questions: Can this line possibly connected to some other part of another circuit that could result in this ground short, or, is this line shorted to ground somewhere in the harness trough under the dash? The wiring in this vehicle is in pretty good shape even after 34 years (Vehicle has been setting for the last 10) and I have not found any burnt or scored connections. I have also cleaned all body/engine/and starter connections. My next step will be to take off the dash to gain total access to the harness unless someone with better knowledge can help me.