911Ragtop

Seems like a fuel delivery issue but heres what's happening. I just picked up this 87' 944. Guy said it doesn't run. I have it now and was able to start it drive it out of the garage and onto my driveway and it's never started since. Now I don't even get it to pop. So I've gone through some things. I probably could add some gas, it seemed empty, I put a gallon or so in it, I could add more if I need to. At the moment heres what I've done.
1. I checked the fuel pump fuse, it's ok, I pulled the fuse and dropped a test light on it and it lit when I turn the key, so I have power at the fuse box.
2. I did the DME Relay jumper wire trick it made no difference and didn't start.
3. I check voltage on battery it was 12.4 so it should be ok, it cranks kinda slow though, maybe time for a new starter but we will get that later.
What I plan to do is this:
1. I understand flywheel sensers can affect starting issues, I will look into that.
2. I will run a test light back to fuel pump wires and see if I have power back there. I hear a buzzing when I turn the key but I'm not sure it's the pump or not, my 924s is silent and this buzzing sounds like a fan under the dash more than a fuel pump....
3. I will disconnect the high-pressure line at the fuel damper and see if there's any gas up there. If not we may have a clog.
4. The guy I got it from said the last thing done was a fuel pump change and it ran then stopped working after the work was done, so hmmmm…
5. I did find a pinched line at the back where the fuel line from tank to fuel pump was not in the right slot and seemed pinched by the sheet metal. I did more it over and moved the fuel filter a little to give more room.

at this point I'm thinking if I have power at the pump, it's something physically wrong like a pinched line, damaged interior line, not enough gas in tank, clogged fuel filter (even though it's kinda new looking it can happen when work is done back there and something shakes looks like old gas gunk-crapola etc. could be gunked up filter in tank too, not sure. I think the car sat for a year, otherwise it was "fairly" well maintained. Oh, and I want to try squirting starter fluid into the air-flow sensor and see if I get some action there.

That's it for now. Any ideas? I'm going to the basics now and start from the tank going forward and see how far the gas makes it.

Spring44

While you don't have much fuel in the tank, drain it and check for rust, fuel varnish or asphaltines in the filter screen and tank sump.



edit: The screen can be cleaned with spray carb cleaner. But it is made of very delicate nylon mesh, so don't scrape on it or get rough with it while cleaning. It is a $75 part.

911Ragtop

911Ragtop

Just got the car running. As I suspected based on previous owner explanation of what happened before it stopped running it was some pinched fuel lines at the back. He paid a street mechanic to fix it and they put on a long hose from the tank to pump and I found that totally kinked .it was way too long about a foot should be a few inches .also found the pump to filter line wedged between the metal pump cover and not in the v slot that it should have been . I also found the fuel pump was not secured . (My brother who is a Porsche owner said the pumps have centrifical force and can rotate if not fasted down .maybe that explains how it was running for a while and it stopped .) So after a year of not running the hose was basically glued together because it was pinched in the metal cover and no gas could get through. It took a replacement Porsche hose from the banjo bolt side of the pump to filter and new filter but once I did that the car started right up and ran smooth . (That was a very expensive street mechanic btw, as it lost the guy a lot of money in the sale for not running. We have a saying "what's cheapest is most expensive" that probably applies here.) . Now that it's running I need to bleed the brakes and do a good inspection of everything and some fine tuning tlc etc. And this Porsche is brought back to life.