heres what my fuse box looks like. my black plastic fuse box cover says that my fuel pump relay should be in the hole where there is no relay (second to last on the left), so does anyone know which one my fuel pump relay is?, or if this is even what the diagram that bob posted is referring to?

thanks
scotthttp://forums.pelicanparts.com/uploa...1314298774.jpg
http://forums.pelicanparts.com/uploa...1314298786.jpg

as you probably know, I need a way to not only run the fuel pump with the key in the ignition on position with the engine off and the flapper valve closed, but also the same with the wur, because I dont hand fuel dumping into the cylinders excessively when the car isnt running

The red relay is for the fuel pump. I forget which two sockets will turn the pump on. Also, there is a air flow sensor on the air flow meter and that is what turns the pump on while running. Circumvent the plug and the pump will stay on. But the plug is on the back of the meter and hard to access. THe relay is probably easiest.

james, thanks for the help
scott

Warm up regulator gets juice from terminal 30 on the fuel pump relay. Energize the fuel pump and you energize the WUR. See the diagram posted earlier. Look at the box two boxes left from the fuel pump. Now trace the wire from that box (WUR) to terminal 30.

Again, terminal 87a and terminal 30 need to be connected with a hard wire between the female sockets. If you want to put a switch in that is ok.

The terminal numbers are on the bottom of the relay.

Bob, thanks again for coming through with all the information i could ask for. I really appreciate it.

Ill go give it a try

Thanks
Scott

i wired 30 to 78a on the male ends on the red relay and then plugged the relay into the spot for the relay, and when i put the key into the ignition "on" position, the fuel pump ran, but the engine tried to turn over and start too!! it took me by surprise somewhat because I wasnt expecting it so i turned the key off. i tried it a second time and this time the engine sputtered for a second and a pit of smoke came out of the tail pipe. I am not sure why the wire i temporarily put in is causing the engine to sputter and the starter motor to spin a bit?

any ideas?

as for the fuel pressure. i didnt give the pump a long enough chance to run to build up to the point that it tops rising

thanks
scott

(this was with the two wire connector on the wur unplugged), for the record

I will dig into this a bit and make absolutely sure I am correct on the info I am giving you.

From a quick scan I see that terminal 87 connects to the starter. If a bare wire touched 87 that may have caused the spinning but I am not sure at this point. Back in a bit.

you know, that might have been the case, but i thought about that happening so i spun the wire really tight to make sure i prevented the wire from touching another terminal. I will check and try it again and see if the same problem occurs. Because it didnt feel like the started motor was on full blast, just a random spin which caused the firing of a few cylinders at most. so the starter definitely wasn't fully "on" or running, which leads me to believe that your idea or a strand of the wire might have been barely touching it.

Thanks for the help
Scott

I just went to my 81, pulled the relay and stuck a wire in the 87a hole and the 30 hole. Turned the key to on and the FP started spinning. Can you perform that test real quick?

If 30 is straight down - 87a is to the drivers side of top center.

heres what the wires looked like, they dont seem to have caused that problem to me because they were and are pretty tightly wrapped around the terminals. but a stray strand of copper from the wire does seem like something that would cause the starter motor to spin.http://forums.pelicanparts.com/uploa...1314320911.jpg
http://forums.pelicanparts.com/uploa...1314320925.jpg

This is interesting. That connection looks clean. Maybe doing this vs the direct wire in the hole does something that I don't understand.

Try the wire only test and I will try wiring my relay now like yours and see if the starter spins when I turn the key on.

Edit - I am back and the starter turned over and the car started. The term "jumper the relay" must mean bypass the relay. The wire only must be the ticket.

Edit #2 - I don't get it. There is a single wire that leads from the ignition switch to the starter solenoid. That is it. The key has to be in the start position to energize that single wire. How could the key be in the on position and start the car?

I agree with you last sentence, which is why I was surprised by my original result. I will try again and this time with the relay out, and the wire in the female holes. connecters on the fuel pump relay connector

thanks for the help
scott

See post #12 in this thread. Says the relay acts opposite to intuition. Also read post 13 from Tony.

I also found a couple of threads where they say to remove the relay and jumper just with a wire. You don't jumper the relay - you jumper the connections in the relay socket. Sorry about the incorrect info.

http://forums.pelicanparts.com/porsche-911-technical-forum/592428-broken-down-fuel-pump.html

Edit - I still don't fully get it. Use the wire only and do your pressure testing. Tomorrow I will pull out the multi meter and try to make sense of it (or keep searching for a post that 'splains it to the layman)

CIS troubleshooting.......
 

Scott,

I've been following your posts with interest and you are totally doing it the wrong way!!!!! You don't jumper the FP relay but the FP socket's terminals. When you turn the IS (ignition switch) to ON position, power is delivered to 87A & 86 (shunted at the socket). If the AFS (air flow switch) is working, the normally closed (NC) 87A - 30 would OPEN and switch to normally open (NO) 87 - 30 to close. Normal. But with power from #87A to #30 (jumper wire) and #87 - #30 (now closed) would cause the starter to run even with the IS @ ON position (not start). This is what you are having with the set-up you have. Use a jumper wire with in-line fuse installed.

Who advised you do this test (connecting 87a-30 of the FP relay)? There are hundred of posts about FP tests in this forum. If I may suggest, I would use the following steps for testing the FP relay socket and its wiring connections.

A). Ignition SW @ ON:
1). FP should not be running. Normal.
2). Remove air filter and briefly raise the air plate for a second or 2. Injectors will spray fuel (have one injector pulled out for visual inspection). Normal.
3). To manually operate the FP, pull out the FP relay. Connect terminals 87A & 30 of the FP relay socket (not the relay). FP should run. Normal.

B). Ignition SW @ OFF:
1). Terminal #85 should be grounded. Normal.
2). Terminal #30 should be grounded with a FP connected. Normal.
3). Terminal #87A no power. Normal.

You could run the FP all day and fuel won't go to the cylinders unless you raise up the FD's plunger to cause the injectors to spray fuel. Keep us posted.

Tony

I think I get it now. When there is juice to 87a from the key being on AND the relay in, pin 86 also receives juice, energizing the relay. This makes the connection break between 87a and 30 and creates a connection between 87 and 30. However, there is no juice going to 87 because the key has not been turned to start. The car waits for that "one wire" to send juice to the starter solenoid and the fuel pump will spin., starter spins, car starts, air plow sensor lifts, sending juice to the other side of the relay magnet through pin 85 and cancels the input from pin 86 and the relay is not energized anymore and the connection to 30 is now made through 87a.

By connecting pins 87a and 30 and plugging in the relay the car was being turned over through the fuel pump fuse when the key was switched to the on position.

I did.

A lot of posts in threads refer to "Jumper the relay" when pressure testing CIS. In post 65 I said to connect the sockets but at the end of one of the sentences I said the pins could be connected also. I never have seen where someone said I will jumper the relay and someone else counter with "No - jumper the sockets - not the relay"

I also looked at the diagrams and thought I understood them.

Here is one example. See post # 3 and then your response at the end. It is not fully clear what "Jumped the relay" means.

http://forums.pelicanparts.com/porsche-911-technical-forum/587215-911sc-fuel-problems.html

Haha, tony, yes your first sentence is most definitely correct. I realized that much when the motor tried to start. When I get the chance, I was planning on testing it without the relay and just using a wire (i was getting there). To answer your question "Who advised you do this test (connecting 87a-30 of the FP relay)?"- Bob has been a big help to me doing this test thus far and he was the one who I have been working with who has been guiding me through the test. That said on this part, we have been trying to figure it out, I am not blaming him for anything, and as far as I aware, nothing bad happened that a blame needs to be issued for.

And personally, in response to "you are totally doing it the wrong way!!!!!" I think I am well along on the right track, using a direct wire lead from the two female terminals was the next thing I was going to try.

But that said, thanks for the help, and the wiring suggestions that you gave.

-Scott

Oooops!!!
 

Bob,

You'll be the last person I would think to offer that suggestion. Was there any particular objective why you suggested it? The reason I asked, is that I've been impressed with your electrical troubleshooting analysis and you've been very helpful to many members. Sorry, I didn't agree with the test method but I do like you.

Tony

I just tested it out (with the gauge in line between the wur and the fuel dizzy with the valve on teh wur side).

Results:
22psi with wur unplugged
pressure rose from 22psi to 52psi when i plugged in the wur

i dont know what the pressure is supposed to be, but 22 seems low according to that video I posted earlier.


Thanks
Scott