Porsche Enthusiasts Club Forum
https://forums.tipec.net/

Fuel Problems?
https://forums.tipec.net/viewtopic.php?f=7&t=644		 Page 1 of 2
Author:  madame petrolhead [ Mon Feb 11, 2008 9:25 pm ]
Post subject:  Fuel Problems?
Could one of you kind boys help fix poor Freddie?
My 1980 911sc wont start. This has happened a couple of times before and on each occasion the fuse for the fuel pump has been changed and it has worked fine. However, I have found recently the idling speed is staying too high on warm up, nd last time I started the car it misfired and was difficult to start.

From the technical informatiion I have found my guess would be as follows:

The fuse is ok, and with the ignition on I am getting a spark on at least one side of the fuse, I think it is likely to be the fuel pump relay or a wiring problem to the fuel pump.

I'm going to get someone to take a live to the fuel pump to test it, andif thats working change the relay to see if that solves the problem.

Has anyone else had this problem and can anyone tell me how to find the relay and if its black or red as I have three black relays in my fusebox in the front luggage compartment? Many Thanks :cry:
Author:  EL Gordo [ Mon Feb 11, 2008 9:28 pm ]
Post subject:  Re: Fuel Problems?
Attachment:
CIS_troubleshoot.jpg



does this help at all??

you can also jumper the relay (between 30 and 87a i think but check !!!) this should set the fuel pump off, or, if you can, try wiggling the relay slowly in and out with the ignition on and see if you can hear the relay click and the pump turn over, the red relays are a pain in the arse anyway !!!!!!

Good luck
Author:  madame petrolhead [ Mon Feb 11, 2008 9:38 pm ]
Post subject:  Re: Fuel Problems?
Thanks for your quick response and info, but where do I find the red relay, any idea?
Author:  EL Gordo [ Mon Feb 11, 2008 9:42 pm ]
Post subject:  Re: Fuel Problems?
you have a pm !!!!
Author:  EL Gordo [ Mon Feb 11, 2008 9:43 pm ]
Post subject:  Re: Fuel Problems?
the first relay, the one nearest the windscreen should be a red relay, the black ones are only for the second 2 holes !
Author:  EL Gordo [ Mon Feb 11, 2008 9:51 pm ]
Post subject:  Re: Fuel Problems?
running 12 v to the pump means you will have to take an undetray off, and you need to run it to the BLACK wire on the pump, the 12v can come from the battery direct, or any of the live fuses. Most probably you need to fit a red relay in the first position. I carry at least 2 spares as they are a right pain. the ones on ebay from the states are just as good as the opc and cheaper as well. OPC stock them though if you want to get one in a rush. :D
Author:  EL Gordo [ Mon Feb 11, 2008 9:57 pm ]
Post subject:  Re: Fuel Problems?
Attachment:
relaydiag1.jpg


As you can see the red relay has some destructions about how it cannot be interchanged with the black one, try putting a red one in before you do owt else

ps sorry for so many posts ! I have had cause to become a bit of a relay and fuel pump expert of late !
Author:  madame petrolhead [ Mon Feb 11, 2008 10:08 pm ]
Post subject:  Re: Fuel Problems?
Thanks so much for all your help, Hubby says all the relays in the front luggage compartment are black, but will buy a red one and fit it in position nearest windscreen.

Think you're right about keeping a couple spare in dash just in case!!!

This will keep Hubby busy and in the goodbooks over the weekend, whilst I supervise!

Will let you know how we get on.

Cheers
Lynn
Author:  EL Gordo [ Mon Feb 11, 2008 10:09 pm ]
Post subject:  Re: Fuel Problems?
when you have the red relay (do buy a couple !!) try slowly rocking it and pulling it out, then reinserting until you hear it click, listen for the fuel pump running whilst you do this !! ignition on of course.

gordon

oh and join tipec if you havaent already :D
Author:  ExAudiSi [ Mon Feb 11, 2008 10:18 pm ]
Post subject:  Re: Fuel Problems?
dekandgord wrote:
oh and join tipec if you havaent already :D



Yes, please do.

Thanks for encouraging new members for the North East region Gordon :D
The more the merrier!
Author:  Sean Smallman [ Mon Feb 11, 2008 10:26 pm ]
Post subject:  Re: Fuel Problems?
It would be a good idea to join the club first then get a discount off of the parts you need.
Author:  ExAudiSi [ Mon Feb 11, 2008 10:40 pm ]
Post subject:  Re: Fuel Problems?
Good point, well put :D

The OPC at Silverlink give discount for TIPEC members (well they do for me anyway) so definitely worthwhile joining the Club.
Author:  madame petrolhead [ Mon Feb 11, 2008 11:26 pm ]
Post subject:  Re: Fuel Problems?
Hi Guys,
I'm already a member of tipec, joined in May 07. Absolutely love my 911sc, which has been no problem until now! So have to make him better. Really appreciate all your help, you're all so knowledgeable.
Thanks
Lynn
PS I agree, the more members the better.
Author:  EL Gordo [ Tue Feb 12, 2008 9:32 am ]
Post subject:  Re: Fuel Problems?
dont gofget to let ys know how you get on? any pics of the car?
Author:  madame petrolhead [ Thu Feb 14, 2008 7:35 pm ]
Post subject:  Re: Fuel Problems?
Gordanddek, you are stars!!!!
New RED relay plugs arrived today, we replaced the old one nearest the windscreen (by torchlight @ 7.15pm as Mike was desperate to solve the problem).

Freddie fired up first time, and sounds as sweet as ever. As soon as I've worked out how to upload, will post some pics.

Can we just ask one more question? the relay we removed was black, clearly it should have been red, so we just want to make sure the others are correct.

Before this change the relays at the top of the fuse box in order from windscreen to headlamp, were: BLACK, BLACK, RED.
Having changed the fuel pump relay, they are now RED, BLACK, RED. Can you tell me if this is correct, as we will change the other relays soon as a precaution. From what we've read they sould be changed every five years, as you know they are not the most reliable of things.

Thanks again for all your help, we really appreciate it.
Regards
Lynn :D
Page 1 of 2 All times are UTC
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
http://www.phpbb.com/