1975 911 no spark no start

[hellcat]

please help

So I have done everything i could on this one.
I have no spark, no power cdi which made me move forward under dash. Still cant find problem so bought new ignition switch, with no go and ran power to cdi which sounds good.
I had this problem a couple weeks before the car stopped and played with the keys and it started again. So can i bypass my igniton to the cdi to start car untill i figure this out or im i in the wrong place or any ideas would be helpful..

There is only so many more days to drive the car before the snow comes up here
vancouver bc

thx again

[hellcat]

round 10
i have a hammer and crowbar
anybody need parts lo

starting to follow wires is my nightmare..after reading more posts.
I need you guys living closer to me...

big man under dash for next couple hours..lol

[2.70Racer]

Hellcat,
Chasing wiring can be a challenge. You know that already.
As I understand it, the power to the CDI box pin B when the ignition switch is on is missing.
There are fuses in the left rear of the engine compartment.
Is there voltage present at the fuses when the ignition is on?
The fuse voltage comes in from a connector near the fuses.
When you turn the key, will it crank the starter?
If you have voltage to pin B of the CDI box, the problem is in the engine compartment.
Another check of the ignition switch (when it is turned on) is to lift the CIS air sensor plate briefly. When lifted the fuel pump should come on and pump fuel through the injectors. You can hear the fuel through the injectors. Do this briefly, you don't want to flood the engine.
Do not look for a DME relay, your '75 does not have one, it came with 1984 models.

[hellcat]

thx for help
still chasing wiring
Yes the power to the CDI box pin B when the ignition switch is on or off is missing, hell all those red and two whites have no power?
Those fuses in the left rear of the engine compartment where working with power and
there is voltage present at the fuses when the ignition is on or off on one.
The connector near the fuses with bunch of wires going in looks good a has one red hot wire on.
It crank the starter just fine and fast.

Another check of the ignition switch (when it is turned on) is to lift the CIS air sensor plate briefly. When lifted the fuel pump should come on and pump fuel through the injectors. You can hear the fuel through the injectors. Do this briefly, you don't want to flood the engine. NOW about this ? My fuel pump runs when i turn the key and im pretty sure ive flooded the **** out of that engine but have just unplugged it in the back from two wires till i put one an two together..

Thx again but no power is making me think some thing not grounded..somewhere ??
but i be back in a hour with less hair and some new swear words

thx again 2.70racer
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[HarryD]

Your power for the CDI box should come off of the hot side (unfused) of the top fuse in the engine room. Check for power there.

Check for continuity from the top fuse to the CDI Box connector.

[hellcat]

Ok will do, and let you know how that goes for me..
thx Harry

[Walter_Middie]

NOW about this ? My fuel pump runs when i turn the key

Yes, on a 75, the fuel pump comes on with the key. You don't have to lift the sensor plate to get the fuel injectors to run.

Harry is correct about the top fuse supplying power. There should also be a small white plastic connector near the CDI box. Just follow the red middle CDI wire ("B").

[Walter_Middie]

[hellcat]

the rex
trying that now

[hellcat]

? does anybody know how the fuse III box is wired as i have noticed mine is cracked. Well the bottom line is I took it all apart got a phone call and feeling like a i didnt wire it right to make sure before it move on here..
thx

[Walter_Middie]

http://www.pelicanparts.com/911/911_Parts/Electrical/911_electrical_1973_CIS_add.jpg

[Walter_Middie]

http://www.pelicanparts.com/911/911_Parts/Electrical/911_electrical_1973_CIS_Part2.jpg

The bottom middle has the 3 fuse block.

[hellcat]

thx again as that will help, but electrical part2 gives me a headache just looking at it. I will put in more time tomorrow and let u know how it goes..

thx rex and to all others that helped today..

Jared

[hellcat]

Anybody got 3 fuse part that i dont have to pay 55 bucks to get del plus whatever else the ups guy takes for duty..Dam canadian part stores suck with selection.

[2.70Racer]

Walter_Middie,
Didn't know about '75's and the fuel pump. My experience has been with my '76.
Thanks, good to know.
I'm suspecting a bad ignition power connection at a connector.

[0396]

I had a 74 that would cut out once in a while.. I traced it to the fuse on the fuse panel ( loose fuse).. Good luck... the bright side, you have Whistler to go too.

[hellcat]

Well after much wire chasing. it looks like there is a red wire that supplies power to 3 fuse bar back to cdi comes down the frame rail to behind seat...Where it goes next i will find out tomorrow unless any body knows? Tried to bypass and think i shorted something out at the other end of wire as i get no power in engine area now. The good news being i know the problem is somewhere up front if i didnt do more damage with the short.
Has anybody had any problems up front, went through all fuses, connections under dash , ground wires cleaned up and more..
Plus i must have blown a major fuse to cut power off to rear which i will hunt for after reading wiring diagrams tonight..
I little help is always needed around here......

Thx again

[HarryD]

Hellcat:

Hopefully you did not burn up a wire in your harness. In the future, do not test with power but look for continuity with an ohmmeter. Safer.

The red wire in the engine room should terminate on the power side of Fuse #8 in the top fuse panel.

There is a 14 pin connector in the engine room. The red wire goes through it. Find it and test for continuity bewtween the top fuse in the engine room and the connector. If ok, check for continuity between the 14 pin connector and fuse #8 up front.

Also check for continuity between the top fuse in the engine room and the CDI box.

when working with htese diagrams, it does not hurt to make a large copy and use a highlighter to trace the wires. It makes it much easier to figure out.

Be pateint, electrical problems require a systematic approach.

[hellcat]

will try thx

[hellcat]

Being pateint, electrical problems require a systematic approach and i will start back at a again tomorrow.
Went through alot today and found power to all the right places but not to cdi. So just for fun to end my day i cut that red wire and grounded it, put power from 3 fuse box to it and got cdi working with power to coil, but no power out..? There was no power out of the white wires from cdi to dizzy too if that matters in my last resort to put a smile on my face before i go to step a again later.

Well if your having a bad day just think of me too put i smile on your face....
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