924Board.org

nivekrs · Joined: 14 Apr 2010 Posts: 55 Location: Wisconsisn

'82 924 non turbo fires and then kills. Did fuel volume test off return line and got 750 ml. Did fuel volume test off feed line after fuel filter and got the same. But then I pull an injector and had wife turn car over while I held it into a container and got nothing. Then I removed the injector from the line and just held the line into a container and got nothing as well. Any ideas? I should at least get fuel from the injector and the injector feed line when the car fires for the few seconds, shouldn't I? Need help. I feel like I am at least starting to isolate this problem.

CorsePerVita · Joined: 25 Jul 2008 Posts: 1992 Location: Redmond, Oregon

If the return line shows up good but nothing at the injectors something is stopping it along the lines, and yes, you should get fuel at the injectors. My guess is if you test all the injectors you may fine one or two getting /some/ ???

Perhaps the fuel distributor is to blame.
_________________
- 1977 Porsche 924 2.0 N/A (Trackday Project)
- 1979 Porsche 924 2.0 N/A (The other daily)
- 1980 Porsche 931 (Daily)
- 1987 Lamborghini Jalpa
- 1999 Ducati 900SS

nivekrs · Joined: 14 Apr 2010 Posts: 55 Location: Wisconsisn

Ok, I'll try all of the injectors and their feed lines. I need to isolate this problem more than I have. Thanks.

JoeShmo · Joined: 15 Jul 2009 Posts: 67 Location: Hornell, NY

So are you saying you can actually start the car, and it runs for a few seconds, then dies?

If so, I'm fighting with the same exact problem on a 77 non-turbo. I've taken the fuel filter out, and noticed it had alot of crud in it. I'm guessing (at least with mine) that a piece of debris is holding something open, causing a non-pressure build up, so fuel is going right back to the tank rather than being pressurized. I too have pulled a single injector, and noticed lack of fuel coming out of it, but upon taking the banjo off, there was indeed fuel there, but apparently not enough to fire the injector. Which I thought was odd, because the car did start (not this time, since I just ran the pump, and didnt actually turn it over). So perhaps other injectors are firing.

Additionally, I did go out an buy a CIS tester, and its not holding pressure (drops to 0 as soon as pump turns off).

Will be interesting what you find, if you get it figured out...

nivekrs · Joined: 14 Apr 2010 Posts: 55 Location: Wisconsisn

Absolutely Joeshmo. and let me know what you find out as well. Just hoping it's not the fuel distributor. Although it would probably be easier to get at than a lot of other things in the fuel system. I'm wondering if maybe the fuel pressure solenoid on the side if the fuel system. Have to look it up in Haynes manual.

JoeShmo · Joined: 15 Jul 2009 Posts: 67 Location: Hornell, NY

Have you tried taking out the fuel filter yet? I know you tested fuel flow after filter, but try taking the filter out, and keep it sideways, so you dont lose much gas (if all the gas falls out, you wont be able to get a good look at it's clarity). Then pour from the "in" side into a glass jar, so you can see if its dirty.

Since I'm in NY, it decided its still winter, so it snowed today. Thus, I have not been able to do more work on the car, as I don't like standing in the cold while trying to figure out what exactly to do next, and how to do it.

The part that I'm dreading, and has been suggested might be the problem is a spring loaded "pressure regulating valve" (pg 76, diagram 3.5 in haynes manual). My favorite part about this little gem, aside from all the little pieces, is the removal procedure on pg 75: "...Be careful not to scratch the bore or the piston since these are mated on assembly and a new piston means a new distributor body.". So not only do I worry about scracting, but losing as well... especially since it goes on to say "if the piston is stuck, either blow it out with compressed air, or work it out using a piece of soft wood". Just wonderful. I don't know what they are talking about with the piece of wood, as theres no way to get at it. compressed air, I'm guessing you blow into another port, and have the piston shoot out, and get lost if you dont catch it with your finger over that hole properly.

CorsePerVita · Joined: 25 Jul 2008 Posts: 1992 Location: Redmond, Oregon

isn't CIS fun? you'll want to stab yourself in the face with an icepick soon but don't give up, you'll figure it out. it's only frustrating when it doesn't run.
_________________
- 1977 Porsche 924 2.0 N/A (Trackday Project)
- 1979 Porsche 924 2.0 N/A (The other daily)
- 1980 Porsche 931 (Daily)
- 1987 Lamborghini Jalpa
- 1999 Ducati 900SS

nivekrs · Joined: 14 Apr 2010 Posts: 55 Location: Wisconsisn

Yes, I did take the plug off the pressure regulating valve and the spring did come out. The piston didn't seem to want to come out. (I kinda left it alone for the reasons you described) But I did spray a bunch of carb cleaner in there. I wonder if it is stuck in some kind of "open" position, thus my loss of pressure on that end. Maybe I should try to work it out carefully.

joejax · Posted: Sun Apr 18, 2010 12:50 pm Post subject:

Be careful with all the little parts in there, I took an extra dist apart and cleaned it real good.
In my excited hast, a piece got wedged in between the top and bottom and the whole thing is now a paper weight

.
So I cleaned my old one as much as possible, without taking it apart, I do not have another to destroy.
I also had a fuel flow issue, alot of gunk in the tank would clog the filter once in a while. I had to clean the tank and fuel pumps.
_________________
I got nothin'
Uhhh...you got any pics?

nivekrs · Joined: 14 Apr 2010 Posts: 55 Location: Wisconsisn

Well, that is actually where this all started. Tank was horrible. Drained gas and pick up on in-tank pump was completely clogged with rust chips. Changed fuel fuel filter at that time also but I'm thinking I should buy a couple more and change them after each tank of gas till the system cleans it's self out. Of course that will be AFTER i actually get it running. Anyway, it seems I'm working forward and it seems like I'm getting closer and closer. I also changed the injectors when I cleaned the tank. Kinda wish I would have waited to put them in though, considering I've obviously pumped a lot of crud through my wonderful CIS system. Poor thing.

JoeShmo · Joined: 15 Jul 2009 Posts: 67 Location: Hornell, NY

I hate that. I know what I MUST do, but don't want to do it. We both probably need to drop the tank, buy a tank re-lining kit from JCWhitney, and reline the old tank, then clean out or replace the pumps/sending unit, etc.. as well as cleaning out the whole CIS. The important part is starting from the tank. No real pount in cleaning it all out, and replacing things when the cause of the whole mess (rust on the inside of the tank) isnt taken care of.

I've actually contemplated getting some sort of plastic racing fuel tank, and putting it in the "trunk", and running with that for a while. I've been unable to find a replacement tank. I wonder if there is a sort of generic plastic tank that'll fit where the metal one is.

Did you actually take your tank off, and clean it all out, or just clean the pickups/pumps?

nivekrs · Joined: 14 Apr 2010 Posts: 55 Location: Wisconsisn

No, I didn't take the tank off because I didn't even want to get into dropping the tranny. I am a novice (Haynes manual) Mechanic. I don't have the knowledge or the resources for that. I simply drained the gas via the return line inlet on the tank and then poured about 5 more gallons through till the rust chips stopped coming out and then wiped out the expansion tank as best i could through the outlet hole with a rag till it looked clean. Not the best job probably but all the scaling is gone and once it's running right,I intend to simply keep the tank full at all times and I think that should keep it from getting worse at least. Now I have 2, 5 gallon gas cans full of cruddy fuel I need to get rid of before my wife tries putting it in the lawnmower Lol.