924Board.org

[Lakeview]

@scm924s

Thanks. That was what I was thinking. My first time doing it and it's a learning experience.

It just didn't seem to go together just right. The barrel part just didn't seem to seat in the head and the top of the orings were sticking out a little. I think they should not.

I'm going to disassemble it today and not sure what that result will be since I used the blue sealer. I kind of wish I hadn't used it now.

[scm924s]

Rebuilding a fuel distributor is not something to be undertaken lightly and i admire you for doing so. However it often results in failure which is why there are professional firms carrying out this work, but not cheap. There are a number of on line guides showing the procedure, just have to be methodical, not sure if any use a joint sealant.
_________________
1984 n/a Ruby Red Metallic
1988 924S Guards red- sold
1986 924S Guards Red - sold
1984 n/a Black - sold
1980 n/a Le Mans#1 - sold
1980 n/a Le Mans#2- sold
1977 Martini - sold

[Lakeview]

@scm924s

I'm finding that out real quick!

I guess you would say my first attempt is a failure. The more you do something the better you get at it...

Disassembled it yesterday. What I found was that when it wouldn't go together and I used the screws to pull the halves together one of the rings around the filter got lodged in the housing. I didn't have the nut end seated all the way in the housing. It put two gouged places in the casting, shredded the orings and the oring at the nut. I used a little emery cloth to try and remove the burred areas. Filter is a little deformed. It should have a new one but I don't see any available online.

I put it back together. This time I tapped the barrel part in with a hammer to seat it. Removed the sealer from one side. The missing parts guide to assembly shows using the sealer if you think the mating surfaces are not true. It went back together fairly easy this time. I had to use the old orings though. I'm going to install it today and see what happens. I don't have very high hopes of it working correctly and not leaking.

I guess I'll be buying a replacement to rebuild if anyone has one laying around. I can't afford to buy a rebuilt at $500 plus. I feel confident when I find another to rebuild it will be smoother.

Looking online a lot of versions, same casting but with different part numbers. What would be the difference? Port sizes, spring rates and such?

[Lakeview]

Update........

I successfully went back through the fuel distribution head and corrected my mistakes. Installed on the car. Amazingly everything seemed normal but I only had fuel on cylinders 3 and 4. I removed the head filters and then had fuel through all lines. I had cleaned the injectors but after installing on the lines only one would spray. Removed the other two head filters. A little better but flow was sporadic.

Bought four new injectors. Changed fuel filter. Purged line before filter. Checked flow at lines and appeared to be putting out the same amount of fuel. Installed new injectors.

Now, car fires but only for about a second and will not stay running. I had installed the kit in the WUR so I'm thinking it's not the problem. Then it seemed to quit firing at all.

Thinking I may have fouled plugs I started checking that. I had no fire on the plug. Investigating that problem and checking the coil wire I found it had no continuity. Replaced it with an old crusty one from my 66 912 and have fire again but still will not run.

I have turned the distributor head screw back and forth from lean to rich with no change.

I guess my next move is to replace the spark plug wires even though they look brand new. All this troubleshooting is exhausting!

And, the only place I see to buy distribution head filters is from missing parts. Are they available anywhere else? Maybe in the states to speed up replacements?

[Raize]

Running on cold start valve fuel I'd imagine.

Coil positive wire has to be OK because you disconnected the one from the starter in your other thread. Unlikely to be plug wires. You can test these with multimeter, should have several KOhms normally - if they show infinity then they're broken.

Can you make it run (even a little bit, even if it's horrible) by giving it throttle at all or is it completely un-cooperative?

[Lakeview]

@Raize

It's completely un-cooperative. Will run for a second and die. No throttle response.

With the new injectors and getting a good even flow from all the lines I would think it's getting fuel. I pulled one injector and checked fuel spray and it looked good.

I ohmed the coil and it checks ok. That's when I checked the coil wire. I didn't check for ohms just continuity. Not sure if new style wires should have continuity if they are carbon core maybe. But when I installed the old vintage coil wire I had fire again. Hell, I've replaced everything else and new wires are not that expensive even though these look fairly new.

I guess my next step is to pull each plug. Check each wire and make sure the plugs are firing and rule out them being fouled. Plugs are new but cheap ones I threw in.

[Cedric]

Maybe try to run the test where you put the injectors in bottles, rund for 30s and then put them on scales to see if they spray close to the same amount/reasonable amount, it can be done at full plate opening and low opening. You can also check that they start spraying at the same time when you start lifting the plate slightly.
_________________
1980 924 Turbo
www.instagram.com/garagecedric/

[Lakeview]

@Cedric

Yep, I've done that. Had good even volume from all four.

Yesterday after @Raize last message thinking I may not have all the cylinders firing I removed each plug individually to check for fire and make sure no plugs were fouled. I went back and removed number four injector. When I pushed the plate up it shot a tremendous amount of fuel out. When I assembled the distributor head I didn't add any shims to up the pressure.

I'm wondering if excessive fuel pressure could cause a problem? I don't have a fuel pressure gauge to check. Could the accumulator be bad? I've watched some YT videos on updating the WUR to dial in fuel pressure. How necessary would that be?

I'm use to working on late model cars where you plug in a scan tool and be able to diagnose a problem quickly. Not the case here though. I tried unplugging the WUR and cold start valve and it didn't won't to fire at all then.

Is there a way to fool the system?

I have obviously caused my own problems as the car had run before. Idling fine and getting up to temp and fan coming on. I'm missing a piece of the puzzle!

[barnwerks]

To work on the CIS system successfully, a fuel pressure gauge assembly with a bypass valve is a necessity, it is the equivalent of a scan tool.

[scm924s]

[Raize]

[scm924s]

[Lakeview]

For some reason I have not been getting notifications about this....

@scm924s. The car hasn't run so the injectors weren't under pressure at that time. I was just trying to see if I had pressure after replacing the injectors and new fuel filter.
I joined the 924UK site when I started this adventure. It has been very helpful since other than my engine problems with the list of other issues I have addressed. That list is getting long. Tie rod ends, rear shocks, hatch seal, hatch shocks, tail light seals, ignition parts, sway bar bushings, headlight switch, brake light switch and more. Chasing an electrical issue with the tail lights not all working. Not having the correct information for a 1983 Euro version is a problem. My US Porsche factory manuals and Haynes do nothing for wiring troubleshooting. Everything is only up to 1982.

@Raize. I have removed the WUR again and found the inlet screen clogged with gook. Removed the screens (only had 3). Disassembled and made sure everything looked ok inside. Installed. It would fire off better but still not run. Still not having a pressure gauge I removed the top line off the head and pressure seemed low. I added the two shims that came with the rebuild kit. Seems to be better but not enough. Car would start enough for me to grab the plate and when moving up it would die and no throttle response. I removed the AAV when I removed the WUR. AAV is closed with only the little notch showing. I use that reference from looking at the rebuild kit. I will try the unplugging AAV you are suggesting but it probably won't change. I think my problem is that I damaged the head when I installed the rebuild kit the first time.
I am currently looking for another 005 head. They seem to be more available in the UK and Germany.
I have watched a lot of "grey goose" YT videos about Jetronic. I will be either making or buying a fuel pressure gauge next. I have learned quite a bit about the system but still not confident in my diagnostic skills!
This being a euro car not much printed diagnostic material. Using 82 and back US information is not helpful.

[Lakeview]

Oh, and something I forgot to mention.

I checked the WUR when I had it off. The element shows 20 ohms. When using my almost useless diagnostic manuals checking for voltage at the connector I don't have any. Manuals say to unplug "can't remember the term" at the moment but I believe it is referring to the sensor on the air cleaner housing. Car doesn't have one. Nor does it have an oxygen sensor.
I checked for voltage across the two pins only. That's what the manual shows and not each to ground.
How do I tell if I'm getting voltage and at this point with not starting does it even matter?

[924RACR]

Not all that critical given the no-start.

That and the aux air valve should both get power from the same circuit, with the fuel pump.

Yeah, you REALLY oughtta have better manuals if that's the level of assistance you're getting...

Ready for the EFI conversion yet? LOL
_________________
Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype