1978 280z will not start without ether

[crash131313]

holy $^!# it started on its own!!!!!    i tried just turning the switch from on to start very slowly and it started right up.   that must be the problem.  just a dead spot in the switch.   thank you thank you thank you!!!!

[KSRosser]

Sweet!


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[Dave WM]

Hope so, now pull that switch and test it. You may have a different check to make depends on the year, but if you get the intermittent contacts, then replace it with a new one.

[Captain Obvious]

Cool! That sounds promising. And cheap.   

 

[crash131313]

new ignition switch is ordered and will  be here tomorrow.    ill let you guys know as soon its working. 

[crash131313]

it was only 25 bucks.    is it a pain in the butt to remove an install the new one????

[Dave WM]

very easy. Just remove the bottom shell of the steering wheel clam shell cover, there are different types of screws so note what goes where and don't miss any.

GENTLY remove the plastic bottom only (leave the top in place) of the clam shell. if it resist check for any screws you may have missed. get under there and look with a flashlight.

unplug the wire harness from the back of the switch. IIRC there are 2 phillps screws that hold the switch assy to the lock assy (no need to remove any of the lock assy). Maybe a little tight fit, I think I had to use a smallish screwdriver, but not sure. I know it can be done without any further disassembly.

TEST the new switch. Always test electrical parts like sensors and switches BEFORE putting into service. This will prevent massive headaches if you happen to get a bad one (it happens). After all where is the last place you would check, why the new part of course if there is a problem. I can not over emphasize this need to test while its out, easy to do, only takes a few minutes.

reverse the process with the new switch and done. 30min max if you take your time. Be gentle with the clam shell, old plastic does not take well to rough handling, and do NOT overtighten the screws, its just plastic and will strip easy. just snug it up till you feel some resistance and stop.

I still think you should have checked the old switch 1st (remove it and test as in the video). I just like to know for sure something is broken before replacement, but it likely is the cause of the hard start if you can start the car by careful manipulation of the key.

 

 

 

[Zed Head]

I used to struggle with getting the lower half of that clam shell off of the column until I realized that the trim ring on the ignition switch will pull back about 1/8 inch.  The extra room allows it to slide off pretty easily.

Agree with Dave that more testing would have made things more clear.  Still not really clear why the "slow turn" worked, and why you saw spark, but it wouldn't start.  There's only the ignition relay and the starter motor involved, unless somebody modified your wiring.  Won't be surprised if the problem reappears.

[Dave WM]

I had the same kind of problem, in fact when I went to buy the car the guy would some times break out the ether to start it. I struggled with an intermittent start up issue for a year, doing all the normal test (check for spark, check for fuel pressure while cranking). Sometime it would just fire right up, I even thought at one time it was a lean mix due to the thermotime not working when it was not really cold (I was desperate). I even went so far as to change to a 85f (think the OE is more like 70f for cut off) hoping the richer fuel mix would be easier to start. I check everything, even did a video where I was convinced it had to be the CSV (seemed to hot restart ok) and of course if fired right up, I had planned to manually fire the CSV to confirm my beliefs, much to my chagrin on the video.

It would seem that during the actual testing phase everything worked fine some times and other it would struggle to start (would always start eventually after a lot of on off cranking episodes).

I don't recall the specifics as to why I decided to check the switch, prob read on one of the forums under the heading "starting problems". The biggest takeaway was to check the switch out of the circuit where you can really check it closely, this only applies when the problem is intermittent and cant be traced other ways. That's why I prefer to test 1st before replace, if it test fine there is no reason to replace it BUT if you have dead spots where the IGN drops out while in the START position, well certainly that is not good so a case can be made to replace with a KNOWN working switch (hence test before install). May not be the answer but with intermittent you have to sometimes use trial and error approach, or wait for complete failure then you can check easy.

here I am getting ready to "prove my point" about the CSV ha

 

Edited October 5, 2017 by Dave WM

[crash131313]

well guys i recieved the new switch (aftermarket NOT oem) and i seems to have the same dead spot but not as bad to where the car will finally start on its own without ether. but only if i barely turn it to the start side.    i just ordered the oam switch for only a few bucks more (should have done that from the get-go)     but at least it is starting and running great now.     again thank you all for the help. it has been very much appreciated and would have probably cost a small fortune and a ton of pride to take to a shop for such a small problem.    i will let you know as soon i get the oem switch installed.          thank you thank you thank you!!!!!!!!!!!!!!!!!!!!

[JSM]

9 hours ago, crash131313 said:

well guys i recieved the new switch (aftermarket NOT oem) and i seems to have the same dead spot but not as bad to where the car will finally start on its own without ether. but only if i barely turn it to the start side.    i just ordered the oam switch for only a few bucks more (should have done that from the get-go)     but at least it is starting and running great now.     again thank you all for the help. it has been very much appreciated and would have probably cost a small fortune and a ton of pride to take to a shop for such a small problem.    i will let you know as soon i get the oem switch installed.          thank you thank you thank you!!!!!!!!!!!!!!!!!!!!

Awesome.