Engine Not starting

[pokeytom]

1977 911 S- Drove her home 8 days ago, ran just fine. Went out to move her and she would not start. Please give me some ideas. Frustrated.

[E Sully]

Details. Does engine spin with starter, battery voltage, does fuel pump run, will it respond to starting fluid.

[boyt911sc]

What engine do you have? Carb, CIS, etc.? What preliminary tests have you done so far? Any previous sign/s before this incident?

Tony

[pokeytom]

Baterry strong and motor spins great. Don't know about fuel pump or starting fluid. 2.7 CIS. Runs so good then nothing. I'm frustrated big time. HELP.

[ossiblue]

Originally Posted by pokeytom

Baterry strong and motor spins great. Don't know about fuel pump or starting fluid. 2.7 CIS. Runs so good then nothing. I'm frustrated big time. HELP.

Try this to see if the car will start.

Remove the air filter. Turn on the ignition switch and go to the engine compartment, reach inside the intake and gently lift the plunger. You should hear the fuel pump run and within a second or two you should hear the vibration or squeal of the injectors emitting fuel. Only hold the plunger up for a few seconds--just until you hear the injectors. Now, try and start the engine. Does it start? If so, how is it running/idling? Report back and we'll go from there.

[Paulporsche]

Tell us where you live. When did you last do a tuneup? Have you ever had your fuel pressures measured and your CO set by someone w/ a tester?

[timmy2]

Swap the red relay in your fusebox with a black one and see if it starts. If so, get a new one.

[SchnellSchweitz]

Do not spray starter fluid into the carburetor. Don't ask how I know. ;-)

[pokeytom]

Originally Posted by timmy2

Swap the red relay in your fusebox with a black one and see if it starts. If so, get a new one.

What's the difference between red and black relays?
Thanks

[ossiblue]

Originally Posted by pokeytom

What's the difference between red and black relays?
Thanks

The red relay has an internal diode which prevents electrical feedback when the relay coil is suddenly discharged.

BTW, if you perform the check I suggested it would tell you if your relay is working, as well as priming the system for start-up. I didn't want to overload you on possible reasons for your non-start but the simple procedure (and the results) will move you a long way toward identifying the issues you may have.

[timmy2]

So, in keeping with the K.I.S.S. principle.....
There are 3 things you need to have a running motor.
They are fuel, spark and compression.
We have given you the first few clues to determine if there is fuel.
What you should do is perform the tests as suggested and quickly report your findings back.
Then the members here will help you with what to do with those results.
We all want you to learn and get your car running again.

Here's some cis reading for you to get up to speed on the seperable parts and to comprehend the individual device terminology and function:

Auto-Solve Diagnostic Assistance
CIS Primer for the Porsche 911

[timmy2]

pokeytom,
I did a search on your past posts and from what I've seen you have CIS with all new parts in the last 2 years, a pop off valve and a large mechanics bill.... You also don't seem to post what your results are for the people that offer you help.
Check to see if the pop off valve in the airbox is seated correctly (closed tight).
I'm out of here until you post some results.

[ossiblue]

Originally Posted by timmy2

pokeytom,
i did a search on your past posts and from what i've seen you have cis with all new parts in the last 2 years, a pop off valve and a large mechanics bill.... you also don't seem to post what your results are for the people that offer you help.
check to see if the pop off valve in the airbox is seated correctly (closed tight).
i'm out of here until you post some results.

+1!

[pokeytom]

There is only one red and three black relays locate under the front bonnet. The relay in the engine compartment is black, there is only one. Are we concerned with the relay in the engine compartment or bonnet area?

[timmy2]

Good morning!
The red relay for the fuel pump is up front in the bonnet.
Just swap it out with one of the other 3 and give it a try.(simple, easy check)

If that works:
The red relay may be in working order just not making good contact, they can work loose and the car won't start.
If you have a razor blade you can slightly open the pins on the relay to spread them slightly at the tips in the x pattern. Try it in it's normal location after doing this.
There are lots of posts on the forum about the relay bouncing out of the socket.
If spreading the pins doesn't help, buy a new relay.

If the relay swap does nothing then it's time to move on with more troubleshooting.

[timmy2]

You will become the person you are looking for with the help of the members here!
Give a man a fish he has a meal, teach him to fish, he will always eat!
Porsche Mechanic

[ossiblue]

You're in good hands with Timmy2, and please post your results of the relay swap.

I'd suggest, however, to still perform the test I suggested with the plunger inside the intake. Your 77 fuel pump will only run when the engine is operating with the starter motor, even if the relay is good. If your problem includes a loss of residual fuel pressure, the cranking of the engine may not be enough, that's why I suggested the plunger test--it determines if the relay is working and it builds pressure in the system for a cold start at the same time--and then some. To wit: If lifting the plunger causes the pump to run, you know the relay is good. If the pump doesn't run, that's your first culprit (there may be more!), and you can swap the relays. If swapping the relay doesn't make the pump run, then your pump is suspect. If the pump runs, you let the injectors spray and the car starts, then you have a residual pressure problem. If the pump runs, injectors spray, and car still doesn't start, you need further diagnosis but at least you've eliminated several possible suspects with one simple test.

Whatever you choose to do, please report back the results. Good luck

[timmy2]

Thanks for the kudos ossieblue, and back at you.
I'm of the opinion the OP has a steep learning curve here, so let's go slow and take baby steps..
Eg: remove airbox cover straps, cover and filter, pop off valve seated? See the lever in the airbox? With ignition on, lift it for 2 seconds. Did you hear the pump run and a squealing sound? Etc.

[timmy2]

Pokeytom,
I'll be out most of the day but others will help when you post your results of these simple tests.
Good luck.

[pokeytom]

GUYS- Baby steps good idea. I will try these tests right away and report back. I'm located in rural West Virginia and don't have good access to the proper mechanics. You guys are allowing me to enjoy the car even when I'm frustrated. THANK YOU GENTLEMEN!