Help with Fuel cut off switch.
 

Hello...I installed a fuel cutoff switch on my 87 using a 3 prong toggle switch. When I tested it it worked fine but then I decided to get fancy and make it light up. I ran a ground wire to the switch and after that, the car would crank but would not start. I uninstalled the ground, same thing. I then uninstalled the switch alltogether, still will not start. I checked all the fuses and found that the "engine" fuse in the fusebox was blown. Replaced it and it still will not start. I checked all the other fuses and the main fuses under the dash and they are all okay. The last thing I did was check the relay under the dash and it too, is fine and working. Im lost....any help would be appreciated. DW_88

Maybe its flooded?

the switch you installed interrupted the fuel pump relay coil, not the actual power wire to the fuel pump, right?BTW, Santiago, if you're still here, I e-mailed you again...

e-mailed you back! :p: ;)


I beleive my TII has the same setup as he does except my switch doesn't light up. :)

Thats correct, I interupted the relay wire under the dash, black with white stripe. At first I only hooked up two wires and it worked great....then when I hooked up the last one, (ground) thats when the trouble started.
Thanks for your reply.

DW_88

I agree that it could be flooded. You know how to do the unflood procedure? Remove the green 40A fuse from under the hood. Crank the engine about 10seconds, then put the fuse back and try to start it again.

I took out the storage bins and carpeting in the back of the car and ran the wires back to the pump itself. Wires come up under the carpet between the seats to the center console. I don't if that is a better way of doing it but I haven't had any problems.

what you prolly did was ground (short) the relay coil power wire by grounding that switch with that 3rd wire, that's the reason the fuse blew...that still shouldn't be screwing w/ you though, if you changed the fuse & removed that 3rd wire. If you had enough amperage flowing through that wiring before the fuse blew, though, you might have "taken out" some other stuff...Let's hope it's flooded!

sorry to hijack again, but I e-mailed you back again, Santiago...

ssooo much hijaking oh well I can't pm you for some reason. :/ But I sent you a reply.

ha,ha, I always got to get the last hijack in!!! you got your requested green, santiago (if I did it right...). now back to the prob at hand-did we ever figure out if it was flooded? (I gotta make it look good...)LOL

Well....it doesnt seem to be flooded. I removed the relay and cranked the engine which is what I did before when the engine was flooded and wouldnt start. No help.....it still cranks and cranks but doesnt even try to start. Are there any other relays or anything between the fuel pump and the front relay ? How about one of those switched that shuts off the fuel system in case of an impact ? Im just trying to think of anything that I may have blown or damaged trying to do this. Guess from now on I'll simply follow directions and not try to get too fancy. THanks to all who replied !!
DW_88

Ok for one have you checked for spark?

Santiago, I sent you another e-mail,it's IMPORTANT. O.K., back to the prob- can you hear the fuel pump come on at all when the ign switch is on? (probably run just a couple seconds)...can you smell any gas when you're cranking it? the AFM has the fuel cut-out switch in it, but if you're cranking her & she's sucking in some air it should be allowing the pump to work...what RELAY are you talking about pulling to crank the engine over?

Yeah they are the right injectors man. :)

COOOOL.....ya still there, DW 88?

The relay by the steering column. Thats the one that I cut the wire to add the toggle switch. Ive always just simply pulled that relay and cranked it over, it would run for a few seconds and then stop. Replace the relay and it would start right back up again. Still confused over all this....one little ground wire.
DW_88

Whats that AFM thing your talking about ?? The fuel pump is in the tank isnt it ? I need to pull the carpet and remove that little cover to be able to get to that dont I ??

you sure that relay is still good after yankin' it & putting it back in that many times? did you check to see if you pushed any terminals out of the relay socket? WHY are you pulling the relay if you have the cut-out switch installed? put the relay in, toggle the switch on/off w/ the ignition key on, can you hear it "clicking"?

Yeah it clicks and stays in. I was actually able to take the cover off the relay and watch it click in and make continuity. I at first thought that it was the problem but it didnt take long to eliminate that one.
DW_88

In an effort to eliminate any other problems, I removed the toggle switch just to make sure that IT wasnt the problem. DW_88

back to the flooding questions...I see Icemark's on... Maybe he can help...

is the fuel pump wire connected properly? These wires are old.

I'm attaching a jpg of the fuel/ignition on a 87/88. The relay in question is the Circuit Opening Relay. You NEED to pull the relay and see if there is 12v on the black/white wire.
https://www.rx7club.com/forum/attach...&postid=893365

And on a n/a car the black/white wire does double duty as you can see in the jpg. And the turbo Circuit Opening Relay is different. It has two Black/White wires.

The AFM plays no vital part in the initial starting of the engine. Heavy imphasis on *initial*. You can see BR wire does the heavy lifting on startup.

Here is a turbo schematic. See the diff? Quite a bit diff.
https://www.rx7club.com/forum/attach...postid=1398836https://www.rx7club.com/forum/attach...postid=1398836

The 15a fuse called X-07 is your ENGINE fuse in the crew compartment.

Well you guys and awesome, keep the suggestions coming. Looks like I have my work cut out for me tomorrow. Hopefully its just something little and inexpensive !! Who knows...maybe someday I will be able to help one of you out !! Thanks again !!
DW_88