Edmonton911

Hello everyone;
I realize this is a common repetitive topic and i have spent 10 hrs reading the other ones.

I just bought a 1980 911sc Targa with 74,000 km. Drove it 125km home, started up next day and then took it to the car wash, came home. Turned it off and then tried starting it about 40 min later. I figured it might have been the hot start issue the previous owner spoke off (need new fuel pump check valve or accumulator as per threads). However from reading on the forums this should not affect the cold start should it? It has now not started for two days. It is turning over. Hooked up a trickle charger to the batter that slowly charged it to full and said the battery was 90% of original capacity. Took the two most forward spark plug wires off on the driver side and hooked up a spare plug... it sparked for both. I know i should hear a buzz of the fuel pump when i start the ignition... there an annoying one from the dash but if i turn the key off and then on again there is a very high pitch and quiet sound... is this the fuel pump working?

I am going to try and find one of those fuel injection pressure gauge kits at the local part source but if someone could explain to me where to hook it up on the CIS that would be greatly appreciated as I am a big time newbie to Porsches' and aircooled engines in general.

Any help is greatly appreciated.

HarryD

welcome to our BBS. I think you will find all kinds of great help here.

For a car to start/run, you need fuel, air, crank and spark.

You have confirmed the car cranks over, and you have spark. This means you may not have fuel delivery.

You can check if your CIS injectors are working (and you have fuel pressure) by removing the cover on the air cleaner, remove the air filter, and GENTLY use your finger to slightly push up the air plate inside the inlet plenum. If you have fuel flow, would will hear the injectors "squeal". If you do not hear this sound, the you may have a dead fuel pump or some other component in the CIS system has failed.

You will need a CIS specific pressure tester to get decent results. The shortest path is to find a local shop that is knowledgeable in CIS (it was widely used in the '70-80's by Porsche, Volkswagen, Audi, BMW, Mercedes-Benz, Rolls-Royce, Bentley, Lotus, Ferrari, Peugeot, Renault, Volvo, Saab, DeLorean and Ford) and have them do the testing.

theiceman

.. for a car to run you need fuel , spark and compression ...

i'll be back in a bit as i have to run but no the pump doesnt run with the ignition on .. it should run when you lift the air plate .. id be thinking about frequency valve at this point .. gotta run .

HarryD

Also to help you work on your car, you should get a Bentley Manual.

budge96

check fuse for fuel pump, high whine sound is ignition CDI box

HarryD

Sounds like good advice.

Only for a Bosch box. Permatunes are silent. If he is getting a spark, then he needs to look into fuel delivery first.

theiceman

Back ....

yes you have spark so you are good there .. no you say you just got it right ? how do you know the gas guage is accurate ... are you sure you're not just out of gas ? try throwing in a few gallons first. You can also try calling PO as sometimes they can help if you bougtht it private.

with the ignition on take off the air cover and take out the air filter , stick your hand under there and gently lift the air plate, you should hear the fuel pump run .. it is usually quite loud so no mistake .. be very carefull here as its dumping fuel into your cyliners when you do this . if you hear it run stop immediately, you know its working ..
As mentioned get a Bently or a bosh manual and read about the frequency valve on your car , i think yours has it .. mine doesnt .. those with this setup can chime in also.

Edmonton911

I am impressed by all the quick responses and appreciate all the support. I will try and catch up with some information quickly.
-Thanks HarryD I will try that with the air plate in the plenum as soon as i get home from work. Thanks for the info on the gauge kit. The one i bought at parts source probably wont do much good then... on line it says most cars have a port on the fuel rail for testing... do these cars?
-I checked all the fuses right after i checked the battery (namely the 16th from the front which is for the fuel pump as per owners manual), i have very little experience wtih the european style fuses but all of the metal strips appeared continuous and so I assume this means they are ok.
-I asked parts source for the bentley manual and they do not have it, i will try and find it somewhere if not order from the internet but really want to get my new toy back on the road.
-Thanks for all the help and will update tonight on results of the airplate / fuel injection testing.
-I had the same thought with the fuel gauge so I bought a jerry can full of premium and put it in.
-Iceman who is PO, yes i did buy it private?

Bought the car for $17,500 and appears to be in very good condition so hopefully I have not been had. I will get some pictures uploaded to a site so i can put the url on here. My next thread on here will be asking guys if it has the carrera tensioners or not because it has oil lines running to the cam chain cover and from the pelican parts site it seems like those are only put in for that.

Thanks again for all the help, i feel a little less defeated this morning as a result.

theiceman

PO is Previous Owner ....
Parts Source will never be able to help you with this baby.. dont ever go there as they are
1. useles
2. a rip off..

You should be able to get a Bently on Ebay or Amazon .. Also you definitely need a copy of 101 projects for your Porsche 911 based on your experience .. it is a very good starter book and not only gives you affordable well explained projects , but also things to watch out for, you can get that at pelican or Amazon i would imagine.

Edmonton911

Alright, removed the airbox and put my hand up through the plenum and pushed on the plate... notta, nothing, zilcho, no sounds buzzing or anything. Now how do i isolate and find out which part of my fuel injection it is?
-Thanks for the help theiceman and everyone else... just a little bit more and we will get her going again!

BTW what do most of you use to host your pictures for putting in the threads? I posted a pic below. does my airbox already have the pressure relief valve mod so that you dont blow up your airbox or what is that in the bottom left.

rusnak

Could be fuel pump. Bentley publishing would be a good friend right now. Get the 911 SC Service Manual

Mark Salvetti

Yes, that's a pop-off valve on the left side of the airbox.

Just to be sure, when you lifted the plate and didn't hear anything, the ignition was On?

If your fuse is OK, then you should have power at the red fuel pump relay. Remove the relay, and with the ignition On, you should have voltage in sockets 87a and 86.

How about the fuel pump relay itself? That's easy to check - remove the relay and run a jumper between sockets 30 and 87a. Turn the ignition to On, if the fuel pump runs, replace the relay.

We're throwing stuff at you piecemeal. The Bentley has 16 pages on troubleshooting Fuel Supply. Amazon has one (literally, one left) for $90.

Mark

Edmonton911

Any help until i get my hands on one of those bentley's would be appreciated. i think i am going to get my hands on a fuel pump tomorrow.

HarryD

Here is anther site for Expert help.

http://forums.pelicanparts.com/usercp.php

Oddly enough they sell parts too at this site www.pelicanparts.com.

I would suspect a dead fuel pump but first you need to verify power to the pump. Do you have a volt meter?

HarryD

I use the "manage attachments" function that is included here. You find it on the "advanced screen" or when you reply with a quote.