1984 911, power at coil, no start

[MadeofOak]

I love my 911, but it won't start. Was running perfectly. I did remove distributor cap, and there is good cranking, power at coil.

No spark at closest spark plug.

What can I check? 😊

[GH85Carrera]

There are literally hundreds of posts on no start 3.2 Carrera issues.

Check the DME relay first. If it is old and tired, the fuel pump does not run, or the DME itself gets no power.

Does the fuel pump run for a second when the key is turned?

The speed and reference sensors can fail and need replacement. Don't just throw parts at it, search for no start Carrera and read. There are several great step by step guides.

[MadeofOak]

Fuel pump can't be heard running. Gonna try jumping or swap relay.

[GH85Carrera]

The DME relay is a dual purpose mechanical relay. Mine failed back in 2004.

I bought a German made replacement and that worked until I bought a Focun9 solid state version.

I have my German made one as a backup. It is a really easy replacement to do.

For my car, it was starting fine, but acted like the ignition was turned off for a 1/4 of a second at random. Replacing it cured the issue for me. The DME itself can need an inspection. Often there are cold solder joints or bad components. If you don't have sharp electronic skills, there are a some places you can pick to send it in for repair and testing.

If your crank sensors have never been replaced, I would suggest you order a pair of them, and a new head temperature sensor and replace the head temp sensor "while you are in there" with the crank sensors. They indeed have a service life, and when they fail, it is almost never at a good time or place.

[GH85Carrera]

Look in the upper right of the page, and you will see "Search this Forum" and just hover the mouse over that, and you will see Advanced search. Click that, and enter Carrera no start.

https://forums.pelicanparts.com/search.php?searchid=25153241

Here are over 100 threads to read through. Good luck!

[MadeofOak]

Yep, seat is coming out to test fuel pump relay. I bought a DME 'just in case'.

I did disconnect the negative terminal, did some work and no start. I am reading and reading!!

Thank you guys for your responses and help, just panic inducing when it runs perfect then not... even had a PPI done recently.

Price of Love!! ����

[pete3799]

Did you pull the rotor off when you removed the cap? Are you sure the rotor is seated correctly?

[MadeofOak]

No just the cap. I took it off, cleaned everything but it wouldn't explain no fuel pump wirrr

[MadeofOak]

In the stash just in case!!

[MadeofOak]

Runs!

Um, embarrassing. Took off negative AND positive cables, I forgot to tighten them. Installed quick lever! phewwwee

[MadeofOak]

Going for a rip!!! I should keeper!!

Love that people were willing to help an idiot like me. Love ya fellas!!!!

[MadeofOak]

Boom!!

[83_Silberpfeil]

@MadeofOak - glad for you that you got it sorted out!

I am curious about that black (negative terminal) lever contraption in the foto you posted. What is the purpose, what does it do? It is effectively a "battery quick-disconnect"?

Does it work well and where can I get one for my 83 SC? I've tried a few of the cheap gizmos from Amazon and HF. But they are worthless, never stay on the terminal.

https://www.harborfreight.com/battery-disconnect-switch-97853.html

Thanks!

Originally Posted by MadeofOak

Boom!!

[MadeofOak]

Yeah, it is a quick disconnect, but better! It is a more sure connection. If it's done up! I have it on all my cars as I tinker, but the 911 was left stock and she needdsss POSITIVE CONNECTION!!!

Like we all do! Loveee

[MadeofOak]

Got it from Amazon!

[MadeofOak]

I guess I got to help someone else AND make my 911 better! Great day!!!