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Many many thanks for your compliments gentlemen - it is really heartening that the efforts are recognised, it has been one hell of a battle but the final part begins now Flexi line is in hand and CV bolts are on the doorstep.....

It's raining and I'm on the drive but in the immortal words of Blackadder himself, "What else can you do when the devil vomits into your kettle?" - the rain wont beat me tonight!

Final hurdle - no power to the fuel pump

There's 10 litres in the tank so there is fuel in there, I've checked voltage at the connector near the filter pictured below and nothing there. I've changed the fuse and DME Relay and still nothing.... any ideas?

In the heady days of NASA, engineers who went the extra mile where given the accolade of 'steely-eyed missile man'. So, in recognition of your efforts above and beyond...you sir are 'a steely-eyed Porsche man!'...Failure was NOT an option..

I have followed this thread with interest as like me, you are a fellow driveway mechanic - one hell of a job you have pulled off there.



With regard to the fuel pump, the contacts in the pump connector (pictured) probably need a really good clean and WD40, as it doesn't take much to cause problems. I had a similar issue when I put my 944 back together. Hope it is that.

Thank Rhett

Tried the cleaning out of the terminals (cotton buds and WD40) but there still isn't any power/ voltage at the connector form the car itself.

Tried the DME relay bypass on 30/ 87/ 87b and still nothing although the cable got mighty hot!! so there is power at the DME relay at Terminal 30....

Really struggling on this one now my electrical know-how isn't great

Found the wiring diagram (ref N47) but my limited knowledge on such things mean I cant decipher where the cable go physically on the car - I can see they head up to the top of the fuel tank when under the car but whilst the connectors P5 and 20B could need looking at, I have no idea how to find these on the car....

Any ideas?

Connected battery to the pump and that is fine.

Connected the earth from the pump directly to the earth on the car and connected the live from the connector to the live on the pump - still nothing. There is definitely something between the DME/ Fuse and the connector. Question is what. What is preventing power fomr the DME/ Fuse getting to the connector and therefore the pump...

I can't get my head around the items 20B, L105 or L4 on the wiring diagram or where they may be on the car - HELP, HELP, HELP!!!

Hi, the way these wiring diagrams work is they have a long sequence of numbers running down the side of the sheet, and a sequence of letters running along the top and bottom. This gives a simple co-ordinate system. So, L4 mans you have to find the diagram with a 4 row, and go across to the L column. You will then find a corresponding box with the co-ordinates of where you just came from. P5 is probably the ground point identifier (there should be a key on a diagram somewhere). Item 208 is probably a junction point for several conductors. These usually occur inside the cable form itself, so hard to get to.

The items within the dotted line are all part of the central electric (fuse and relay box). I am guessing that the relay G5 in the picture is the DME relay (it has slightly different name though..). Are you getting 12V across fuse 34 when you turn the ignition on?

L4 and L105 - they appear to be feeds to some other devices, you will need to check the diagram out and find what they are. If the devices that hang onto that conductor are working then the culprit can only be the T45 connector to the pump.

I know you have cleaned the contact with a cotton bud, but you really need to use something a bit more abrasive. Corrosion on those small pins will stop the contact working. I used the tip of a jewellers screwdriver to clean out mine, I couldn't see any voltage on my meter probes until I did that, then I got 12V. Be careful not to short anything out whilst doing that...

Hope that helps a bit!

TBH, from the diagram I cannot see any other connectors involved...keep me informed, I will help where I can!

She lives!

I was a muppet! Traced the connector up to the top of the fuel tank and hey presto, another connector!!





Checked this and made sure it as properly seated which it didn't seem to be and then we had life from the pump until a leak from the one connection that was hidden under the tank cover - yes, the one on the pump outlet



So pipe clamps, dismantle the tank cover, pump undone, cleaned up and back on



and I then tried again with just running the pump first to check for any more leaks - there weren't any - videos will follow

Now tucked up until morning when I'll drop her of the axle stands, tighten the wheel nuts and drive to the MoT

Glad you got it sorted. However, I am a bit surprised that the fuel tank level sender connector was involved...? That is the one on the top of the tank...

Main thing is she is up and running!

It's certainly a strange one Rhett - it is the one on the top of the tank in the photo's... I can only assume there is a cut off in the tank level sender that cuts power to the pump if the sender doesn't read a fuel level to prevent the pump running dry....

But as you say, she's up and running - just need the MoT tomorrow and I'll be heading out for a drive - fingers crossed

Thank you Rhett, Martin, Gryphon, Brian, Dave, Karl, Jase, David, Richard, Adrian, Pilch, Infrasilver, Stu for all your help, advice and support - it has been massively appreciated ^a^ Hope this thread may give some enlightenment to someone trying this again in the future!!

A video of the first start up for your (or rather my) enjoyment!

https://youtu.be/nJOQ5jFYGQ8

The jobs are all done and she is now at the MoT station - I await the call......

Hurray!!! She's passed without any issues or advisories

She just needs a wash and brush up and a bit of polishing

That is really good news!



It's back on the road where all good Porsches should be! Congrats again on a big job well done.

It most certainly is Rhett!

I'm off home shortly and am heading straight out for a drive

excellent news!

many times ive read this thread and been motivated to go out to the garage and crack on with some jobs

a sterling job sir and well done

Brian