If you are saying that the fuel pump is in the engine compartment next to that hose in your picture, then you did not replace the fuel pump. So, what did you replace?

The fuel pump is under the front of the car near the fuel tank.

I'm with Gunter. Get a Bentley manual and do what it says, then come back if it still doesn't work. You'll avoid a lot of unnecessary chatter that is already filling up this thread.

Brett

Calm down Diego. Obviously I meant the fuel filter in the engine compartment. So anyway, I am testing the fuel pump right now and I will update everyone tomorrow.

LOL. I'm calm. Just making sure. In your own words, "I'm new to it... I'm learning." You said the fuel pump was in your picture. I believed you. Be careful what you type. Buy the Bentley. Very worth it. If you won't be taking it to a professional, you'll want a fuel pressure gauge specific for the CIS system, as already mentioned. Once you get fuel flowing, you'll need to check the fuel pressures (system, cold control, warm control, residual), also outlined in the Bentley.

Good luck with it. Keep us informed with progress.

Brett

Thanks for your help Brett. I did connect 87a and 30 withe a wire. I did not hear the pump when I turn the ignition on. Any suggestion?


Thanks

Tony,

I went by the workshop manual (pictures above) and it is interesting that it doesn't apply to a 80 and 81. Thanks for pointing that out!

jrnicl3,

If you bridged the relay sockets as you did and hear nothing when switching the ignition on then it sounds to me like your fuel pump doesn't have power or may be defective. That is, if bridging them has the same effect on your model than on a 79 and earlier, which I believe should be the case. In any event the idea is to start testing the easiest thing first, which is the fuel pump. Before going to the extremes of getting fuel pressure gauges etc.

We need to check and verify this..........
 

Patronus,

I know why this test does not work with the SC's. The '76-'77 have similar FP circuitry as the SC's. I never used this procedure because of the starter cranking and avoided using the factory procedure ever since. The factory shop manual is a super great reference book but the English translation is not that excellent. Which was done some 30 years ago(???). Have you actually performed this test on your car? Please advise. Thanks.

Tony

Tony,

I went through this last weekend when I adjusted my own car's control pressure. It is a 79 SC so the wiring may be different on 80 and 81 models.

I bridged sockets 87a and 30 to get the pump running when the ignition is on, to measure the fuel pressure. I did not bridge the relay because I didn't have an old one as the book says and I though the end result would be the same. It worked perfectly and in fact I started the car and ran it like that multiple times until I was completely satisfied with the end result, and then I put the relay back. As I say, 79 SC may be different from later models.

Got two (2) SC cars and a spare engine.......
 

Patronus,

I've been working on several SC's and just a few weeks ago a member's '81SC engine was dropped at my place for some work. It was tested and run on the test stand using same technique like yours (bridging socket's terminals). Using the socket relay is not a problem. It is the 'bridged relay method' I'm inquiring. Why the factory manual recommended it is beyond me. Have you tried the 'bridge relay method'? Thanks.

Tony

Woah - I said it does not work for an 80 / 81 - NOT TONY.

What I said (re 80 /81) is incorrect because when I did this procedure on a 1980 and 1981 the starter turned BECAUSE I WAS USING A GOOD RELAY.

THE MANUAL SAYS TO USE A SPARE RELAY (WHICH MEANS BROKEN RELAY BUT DOES NOT SAY BROKEN RELAY). THAT IS THE PROBLEM WITH MY APPLICATION

I AM YELLING BECAUSE I NEED MORE COFFEE - BACK IN A BIT.

AH-HA - this may be a simple language issue - Patronus says "old one" / book says "spare" but I think they both mean non-functioning.

It has to because a good relay bridged will spin the starter motor across all the years. EDIT: I also see where I am walking all over Tony's similar discussion. I will sit on the sidelines for a while.


JRNICL3 - Sorry - we will be done with this side bar issue shortly.

Patronus - Looking forward to your response to clarify if you are doing this bridging with a broken relay or a good relay.

I have never modified an old or broken relay, just always bridged the socket (female). I can tell you one thing, if you only expect the fuel pump to buzz but in stead the engine starts running it will be a nasty and potentially expensive surprize. For once I'm glad that I was too lazy to follow the book.

i dont usually jump in on something this long, but its a slow day at work.

wow, you guys turned this into 2 pages about a fuel pump relay. pull the connector off the back of the AFM if you dont kn ow what pins to jump or where the relay is, or just lift the sensor plate.

the car has been sitting for 4 years. could be a stuck plunger. could also be rust in the tank blocking the inlet screen.

pull an injector out, place it in a jar, turn on the key, reach inside the air box and on the left side, lift the air sensor plate.
you should feel resistance as soon as you lift the plate. if there is any "free" movement, with the fuel pump running, which should come on as soon as you lift the plate, the plunger is stuck.
you should hear the injectors squeal and fuel should spray out.


control pressures need to be checked too. a blocked return line or dirty inlet screen to the warm up regulator(WUR) could have the cold control pressure (CCP) too high.

Thanks!!

Both the fuel pump buzzes and the starter turns over but you are so freaked out by the starter motor that you don't have time to notice and you unplug the bridged relay.

Probably the biggest risk is if the car is in gear and it lurches forward or back wards - say, with the front wheels on jack stands.

OK - back to the original post. :-) Thanks again for your patience OP.

All good info - and yes, I played a big part in hijacking this thread. Sorry to the OP.

I believe right now the OP cannot get his fuel pump to operate with either the Jumered relay procedure or the lifting of the air sensor plate.

It drags on mostly because the OP doesn't make it clear what he's doing or what's been done or how to describe things correctly or give a timely response. :(

It's not unique.

A lot of threads start with asking for help, give confusing details, don't follow advise and when the problems ever get fixed, don't bother to tell the rest how it was solved. :(

Sigh.... You are correct.

Fifty five-ish posts in this thread and the OP has lifted the air sensor, sprayed some starting fluid, took a pic of a fuel line and put a wire in the relay sockets.

I think when your serve-return-serve-return (tennis comparison) system breaks down the other posters think that if they post another idea maybe the OP will hear them and come out of the coma.

Maybe the OP bridged the fuel pump relay as per the Porsche Workshop manual and when his wife turned the ignition on the car ran over him....

Who to blame..........
 

If this actually happened to our struggling friend, I know where to put the blame!!!!! OH! It is not you Patronus!!! You are safe. It's the factory shop manual that was poorly translated into English language.

Tony

Glad we worked through that even if it caused a disruption.

Edit - Well, Tony, did the diagram work............................... I just scanned a picture.

Gunter,

Sorry, I have a rough schedule and work on the car at night when I get a chance. I see so many other topics on my thread. I can't help that.

I am still dealing with the issue. I actually did the fuel pump test by bridging 30 and 87a and turned on the key and did not hear the fuel pump running. I went under the car and made a straight 12v connection to the fuel pump and it did run. so the fuel pump(since it's new) is working. I do believe that there is a connection issue with the fuse box area.

Also there is a black square fuse with about 5 flat pins. what is that?


Thanks.

sorry guys, did not mean to sound so rough, just busting your nads a little.

check for voltage at pin 30 of the relay socket. if that is good, you have cut your power problem in half.
next check for voltage at the FP.

That is a good point on the "30" socket. Would you put a wire into the socket and then insert the relay and test the voltage on the other end of the wire once you turn the key to on? Socket 30 gets no juice until the relay provides it through 87a so that would be my guess.

Also jrnicl3 - I can get you diagrams. You need them?

Location/picture?

How to check your FP relay socket..........
 

jrnicl3,

Please do these tests so we could help you determine the culprit/s.

FP relay socket check (relay removed):

a). Ignition switch OFF:
87a........no power
87..........no power
86..........no power
85..........no power; this should have a ground reading.
30..........no power; this should have a ground reading.

b). Ignition switch ON:
87a........has power
87..........no power
86..........has power
85..........no power; this should have a ground reading.
30..........no power; this should have a ground reading.

FP relay test:
87a------30..............has continuity (normally closed).
87--------30.............no continuity (normally open)
86--------85.............has continuity (connected). When power is applied to these terminals, the coil is energized resulting 87a-30 to OPEN and 87-30 to CLOSE.

Additional test (ignition SW off):
To confirm that the AFS (air flow switch) is working, terminal #85 (FP relay socket terminal) should be grounded when the air plate sensor is down. And #85 would loose ground contact when sensor plate is lifted up.

Perform these basic electrical troubleshooting tests to get to the bottom of the problem/s. Otherwise, we would be all guessing at this point. If you have any question, just ask. Keep us posted.

Tony

What Tony says looks overwhelming but is simple if taken one step at a time. You need a multi meter - not even a fancy one. Just one that provides AC/DC voltage tests and ohms (resistance / continuity) Don't let it blow you away. It is "nuttin" Just time and patience.

Yes Bob, Please get me the diagrams. That will be so helpful. Thanks!!!

Diagrams are available right here on Pelican in the Tech section. Click on "Porsche" on top and find the diagrams on the upper left.

Also, the Bentley has the SC electrical diagrams in the back.
I know that the Bentley SC Repair Manual would be the best way to learn and fix all kinds of issues and answer many of your questions. Once you look through it, you'll understand why it's a must have for SC owners.

Once the pump runs, all kinds of other things will have to be done and all the answers on how to are in the Manual. Plus it's so much easier to refer to pages in the manual to answer specific questions you will have in the future. :)

I'll ask again: Will you get the Bentley? And if not, why not?

Yes , I will get it right now.

The fuel pump is fixed and now when I trurn the ignition on, I can hear a high peak noise from the rear engine and The car won't cranck anymore.

also, The signal stopped working. The full light works. Radio works,

Any idea?

You are making it to complicated...........
 

jrnicl3,

You're making a simple troubleshooting procedure into a complex one by not giving us a better feedback!!!!! You are our eyes in looking into the problem/s and we don't know what you have done to fix the FP, if you ever fixed it!!!! Let's go back a little and re-wind.

1). Tell us something how you fixed the FP. Is the FP delivering fuel when you lift the AFS with ignition SW @ ON?

2). The high pitch noise is coming from the CDI. Hope you have a CDI (???).

3). When you say 'car won't crank', do you mean the starter won't do anything? Have you checked your battery and terminals including ground points?

4). Ignore the turn signal problem at the moment. You don't need it to make the engine run. Let's take it one step at a time.

Did you find out why the FP was not getting power? Have you done some of the suggestions given to you?

If you want to fix the problem, help us understand what's going on. We don't know what you did so far. I gave you a simple step by step procedure to isolate the problem and we don't get anything back. Is there a problem why you don't response to the instructions offered to you?

Tony

James

If you turn the key on and the fuel pump runs without the engine turning over something is wired wrong - the fuel pump should come on only when the engine is turning over. That is a safety precaution so that the fuel pump doesn't run when the enigne is not running.

I briefly read the thread because there was too much to say about the problem. So, look at your fuses and make sure all terminals are connected and all the correct wires are on each terminal.

+100!

Please, don't get offended but you need to tell us what you are doing, one step at a time! You have to respond to the excellent suggestions/procedures offered by Tony and others to let us all know what you are doing. Even if you choose not to follow any advice given, you need to tell us that and then explain what you did instead. Seriously, throw us a bone now and then:D. We're here to help but only you can make that happen.

1). Tell us something how you fixed the FP.

I had to replace the the fuse #6(counting fuse from left to right) . As soon as I did it I heard the pump running.
and gas was finally coming to the fuel line next to the fuel filter(of course I uncrew it to check the pressure).

Is the FP delivering fuel when you lift the AFS with ignition SW @ ON?
no, I do not hear the fp delivring fuel when you lift the AFS. There is no pressure of anything on that side.


2). The high pitch noise is coming from the CDI. Hope you have a CDI (???).
Yes, it is and here is the CDI:
http://farm7.static.flickr.com/6100/...4b5954da_m.jpg


3). When you say 'car won't crank', do you mean the starter won't do anything? have you checked your battery and terminals including ground points?

What I mean by 'car won't crank' is that the starter won't do anything.

Yes the battery has been fully charged at Autozone.

What do you mean by teminals and ground points ?

I took more pictures of the fuse area
http://farm7.static.flickr.com/6108/...5aebb90e_z.jpg
What's the following fuse? How many wires should be connected to it?
http://farm7.static.flickr.com/6220/...afa38c71_z.jpg
Where should the wire with the white end be connected to?
http://farm7.static.flickr.com/6222/...06cf418f_z.jpg

What your picture shows is an add-on relay set-up, not a fuse. You will need to find out where each of the colored wires come from and where they lead before you can figure out what it's for. Were any wires to that relay disturbed when you were fixing the FP? That could be a relay for the starter and that may be the cause for your failure to "crank", but you need to be sure of the wiring. Let us know if you disturbed that set-up in any way, or if it is exactly like it was when the starter was working.

Looks like a rusty relay which may not even work? Add-on relay for starter?
Follow the wires to see what it's suppost to activate?
Some of the wiring and stuff is not original and it's hard to say why or what for?

As soon as you get the Bentley, go to page 971-2 and check each fuse for correct size from #1 to #21.

Then, you can follow the wiring from the starter solenoid back to the ignition switch.

See Will Ferch's post #13 in this thread. That relay is probably for upgraded headlights and has nothing to do with your engine.

http://forums.pelicanparts.com/porsche-911-technical-forum/594358-fuse-box-layout-help.html

I am going to hold back on sending the diagrams (sorry for the delay) as there is value in all of us being on the same page - meaning - obtain the Bentley manual.

I guarantee if you keep us advised and hang with us, even if you are frustrated, we will get you going.

Wow, Just got the Bentley Manual. Now I need to spend some time to understand how to read the diagram and start troubleshooting.

So, My wife was helping me out. she was turning the key on and I was in the back listening to what was going on. I could heat a "click" noise from the black relay and also a humming noise from the CDI unit. But the car will not crank. Won't start.

I have no clue about which step to take. Should I replace the coil, distribution cap, the CDI unit all together?

I have the bentley book and does not know where to start.

Thanks for your help