CIS troubleshooting.........
 

Diederick,

You still have to test your car for both cold and warm conditions. If your engine is already warmed up, do the test multiple time. And let the motor cool down at least 3~4 hours to do the cold start test. Hook up the pressure gauge and monitor the cold control pressures until it maxed out and stabilized to WCP.

It would be nice to have the control fuel pressures transition data every 30 sec. or 1 min. intervals. I do this all the time when I am evaluating a WUR and save these data.

Tony

Hi Tony, I keep a stopwatch and note the pressure every minute. I'll post the results of my next attempt. Something that keeps bothering me is why the system pressure won't rise. The FD is rebuilt, the pump has been changed, the filter has been changed, I shimmed the pressure regulator up but it still maxes out at 4.5 bar (65 PSI).

System fuel pressure.........
 

Diederick,

Do you have some extra shims (0.1, 0.2, & 0.3 mm) available? Just for curiosity, add some additional shim/s like 0.30 mm and see if you could get the system fuel pressure to increase. If you added a 0.3 mm or more shim, the fuel pressure reading should show an increase. If there is no change, either pressure gauge or the primary valve pressure regulator is questionable.

Tony

I've added the shims of my rebuild kit and that made no difference. I'm currently running 4 shims measuring 3mm in total. I don't have any tiny shims like this lying around. I measured an OD of 6mm and I'm not sure what to use else.
What's the primary valve pressure regulator? Is that the piston in the bore of the pressure regulator in the FD?

Just for comparison..........
 

Diederick,

The fuel distributor that is mounted on my CIS bench tester is set at 72 psi. that I use regularly for calibrating WUR’s for normally aspirated CIS. Occasionally like today, I tested a WUR-054 (for 930/turbo) that belongs to a local friend.

I removed the 2 thin shims (72 psi.) from the pressure regulator and replaced it with a single 3.8 mm thick shim made from a 5-mm nut set to deliver 95~100 psi. system pressure.

Your fuel distributor is capable of delivering as much as 100 psi. or more system pressure provided you have a good working and correct FP. This is something you have to check and verify.

Tony

I'm pretty stunned by my test results of tonight. First of all, I should mention my optima battery measured 11 volts during the fuel test. I suppose the past feel test and cranking have drained the battery. Could this voltage corrupt the test results?

I installed my quality manometer onto the pressure kit and set about measuring pressures. System pressure was 4.3 bar and switching to cold control pressure the gauge showed 0 bar, warm control pressure ended up being 1.5 bar. I punched the WCP to the low end of the range 2.7 bar. Spec is 2.7-3.1. Applied vacuum only gave 3.1 where spec is 3.4-3.7. Will check CCP tomorrow when all is cold. However, I'm stunned all was in spec with the little gauge installed. No idea why pressures were so low again.

Also, during the fuel pressure test, which lasted no longer than 10 minutes, I heard a tiny injector squeeze every now and then. I backed off the mixture just to be safe. However, this leads me to believe the FD is leaking internally (again?). The main thing holding me back from purchasing a rebuild FD from a renowned Europe vendor is the steep price but I'm kind of fed up with this FD. Could the FD be the culprit of all this misfortune?https://uploads.tapatalk-cdn.com/202...391c6dfa1b.jpg

Let’s test and evaluate your FD.......
 

Diederick,

Wished you reside near me and have all your CIS components tested and evaluated for FREE. I offer this service to assist fellow CIS owners get their cars back on the road plus it makes the troubleshooting much easier if these critical components are good and working.

Your problem/s could be attributed to several factors.

• The gauges could be defective.
• The CIS component/s could be out of spec.
• The power supply from the battery was low.
• And many others.

These are the tests I use for evaluating the FD:

• The FD plunger moves up and down freely with very light resistance. Note: No residual pressure in the FD when doing this test.
• Disconnect all the six (6) fuel lines to the injectors and place the ends in appropriate containers in case we have premature fuel delivery. Test run the FP with a fully charged battery. With plunger at rest, there should be no sign of fuel delivery or fuel drips.
• When you raised the plunger up while the FP is running, fuel would be delivered to the injectors in equal volumes. Using graduated cylinders to measure each flow rate is recommended.
• While the FD is under pressure (FP running) inspect the perimeter of the FD for any sign of external fuel leak.

Keep us posted.

Tony

Tony, I wish I had taken you up on that offer last year when we were sending PMs. That would have been priceless but unfortunately COVID, shipping and custom duties complicate everything.

Actually, Ruben from missing parts had me run those test on the FD too. I sent him data of measured quantities for 20 seconds of half lift and full lift of the metering plate. He was happy with the results.
Before the rebuild the injectors dripped, so I replaced all of them. With the injectors off I noticed that 2 injector lines would get some fuel when they weren't supposed to. All seemed fixed up until last night when I heard the squeeks during the test.

All in all, the rebuild took three attempts. After the first go I had 5 bars of pressure and I was over the moon. However, seconds later I noticed the two halves weren't sealing. So I took the halves apart and applied his supplied sealant very lightly, yet this attempt the tiny control pressure hole gunked up. The third attempt was with loctite 574 applied super thinly to the halves and that has sealed well.

But the SP never got to 5 bars anymore. I'm blaming the FD for most of my problems. I'll give it another go with fuel battery charge today and perhaps decide then. Purchasing an expensive item that hopefully solves this problem is about as expensive as the labor bill if I give up and have to outsource the problem.

Did you fix the oscillating plate problem ?

The FD and WUR have been send out to a specialist. I gave up trying when I went back to the car and CCP was over 3 bar whilst I set it to 1.1 when I left the previous time. No idea what was going on... I'm hoping the engine will run when he's done with both.

Sounds good.

I would do the same, send it out to a pro, if the FD is suspect, given the intricacies of that device. The oscillation brings to mind system behavior where the response is too fast without enough damping resulting in the fluttering. When you get the parts back, it would be interesting to install just the rebuilt FD and see if that fixes it.

So. Almost one year later and the car still isn't running (right). I have since acquired nearly all items for a Triumph ITB swap but I want to give CIS one last go. Heck, it's spring/summer and yet again I'm not driving the 911.

Where I left off last year is having the FD and WUR rebuilt by Ruben of Missing Parts in Germany - I believe Tony knows him too as he is a specialist and sells the hard-to-get parts. Fuel pressures tested out well at Missing parts and fuel delivery was good and equal among the injectors. However, when I installed the FD on my engine the system pressure still didn't go above 4.5. This is at the lower spec but not very high. Shimming the pressure regulator in the FD didn't make a difference. The fuel delivery test at the FD gave just under 500ml instead of the required 750ml+ that the books states. However, fuel delivery test at the WUR was in spec. This leads me to believe there is a blockage of faulty item in the chain before the FD that is working against me. Eventually and after double checking the pressures with a separate fuel test kit that I have I changed the fuel pressure on my adjustable WUR so that it got near spec.

Cold pressure is 0.8 @15C
Warm pressure is 3.3 w/o and 3.7 with vacuum.
System pressure is 4.5 bar

Cold is a little low for my liking and warm is a little high. Ideally warm should be 2.7-3.1 w/o vacuum. But IMHO the pressures are close enough to make the engine run OK.

Here's the facts.
Fuel pump - New Pierburg replaced last year
Fuel accumulator - might be culprit as it's one of the few items not replaced.
Fuel filter - New Mahle replaced last year.
FD and WUR rebuilt by specialist.
AAR tested in freezer and closes in 7 minutes.
NOS Thermo valve installed.
New injectors.
AEM AFR gauge present.
And I have a permanent pressure gauge installed.
I set the sensor plate yesterday and set the mixture again according to the Klassik Automotive Training School videos.

I purchased a smoke tester last year too and did a smoke test yesterday which shows no leaks. All rubbers and sleeves etc have been renewed on this journey and I have an aluminum housing that I purchased from a Pelicanite to assure a leakproof system.

My car is parked in an underground garage which makes it a little hard to let it warm up and idle without being frowned upon, but this morning I drove a few laps in the garage. AFR started in the 10s and the car bogged the first few meters but I let it coast and it went better after one lap. I saw the AFR rise slowly into the 13s and 14s when I opened the throttle - which seemed odd to me. I stopped after a few laps and checked my pressure gauge at idle (900rpm). The fuel pressure had risen to warm already and it was around 3.8 and when I pulled the vacuum line it dropped to 3.3. AFR was around 13.8 so that seemed to go well. But when I pressed the gas pedal in neutral the engine stalled. And it refused to start again - endless cranking and it felt like the engine was running at 250rpm and wouldn't catch. Disconnecting the cold start injector made no difference.

In my view there are now two issues besides fine tuning the mixture (which doesn't seem to be too far off):
- revving in neutral makes the engine stall
- engine won't restart. I don't know if this already qualifies as a warm start.

Residual pressure should be 1.5 bar at 10 minutes and 1.3 at 20 minutes. But after 10 minutes the pressure had slowly dropped to around 1 bar. Could the accumulator be faulty? Maybe the accumulator is also to blame for restricting the fuel pressure and delivery? Should I go out and purchase a new one? They aren't cheap so I'd rather be sure.

Also I don't want to be throwing money at the CIS by replacing the last items that I haven't yet: Fuel accumulator and thermotime switch as they're both over $200 each. On the other hand I don't want to be throwing in the towel as it hurts not driving the car for so long.

I tried to be as elaborate as possible and look forward to your views.

CIS troubleshooting.......
 

Diederrick,

If I were doing the troubleshooting, I will check these:

• Residual Pressure Loss.
• Test the FP for max. pressure capacity.
• Confirmed that the air leak test created a positive pressure in the air box.

You could bench test the FA. The actual test would only take several seconds. It would be either good or defective. The fuel pump test would also takes less than 10 sec. to confirm whether the FP is good or not.

And the most important thing is doing the air leak test correctly. You need to isolate the system (airbox) and confirm that a positive pressure was created during the smoke test. Email me if you need some help.

Tony

Hi Tony,

Thanks for your reply.
I intend to test the FP by undoing the fuel line at the FP and measure fuel delivery in 30 seconds. 750ml should be minimum but preferably 1 liter. If the FP delivers sufficiently then perhaps the FA is leaking fuel back to the return instead of forward to the filter and FD. Correct?

The FA should hold 20" of vacuum is what I read. Is it possible to test that in situ with a little hand pump? Or should I take it out and do some sort of bench test?

Should the FP (which is new) test good then it's hard to imagine the FA not being faulty.
Should the FP test insufficient then it's either the pump or a blockage in the system. Perhaps the fuel filter at the bottom of the tank. No idea if that's ever been renewed but that's the next step.

I would say the airbox creates positive pressure. When tested with my smoke tester I capped off the TB and 90 degree pipe above the AAV with the supplied rubber caps and no visible leaks were identified. Then at some point the airbox was so full that smoke came out of the pop-off valve. I don't believe this to be a leak because a running engine produces negative pressure and would suck the pup-off valve closed so to speak.

The engine start right away when cold but not when warm pressures are present. So I have trouble with a warm (pressure not oil temp) start. I don't yet understand why the engine will drive but not rev in neutral.

CIS troubleshooting........
 

Diederick,

First, let’s get the engine to start both cold and warm consistently. Then deal with the fine tuning of the CIS. You could test both the FP and FA conveniently using a pressure gauge. I have posted several procedures in the 911 Technical Forum and should be accessible for reference. It is critical that your battery is fully charged (12~13 volts).

Confirm that your FP could deliver at least 90 psi. using your CIS gauge and the FA is not leaking. BTW, your WUR & FD need to be recalibrated specially the WUR. Contact Ruben and explain the problem.

Tony

Hi Tony, thanks for your reply! Working from home has its benefits as I went out to test the FA during my lunch break. I undid the line that comes from the FP and put it in a container. Hooked up my remote FP switch and went ahead and tested the delivery. I turned the switch off after 12 seconds because fuel came gushing out and I had already collected nearly 500ml in the container. I was happy because that means the new FP delivers a ton of fuel and the problem lies somewhere in the chain of components between the FP and FD.

My theory is that the FA, being in the chain, sends fuel back to the tank and therefore less fuel is delivered to the FD and hence system pressure has been low as well. So, I'm ordering a new FA. I took the FA out but I'm struggling with how to bench test it.

I know what you mean with recalibrating the WUR and FD. Ruben calibrated those for me but after I installed them the pressure were still low. So, I adjusted the WUR with the allen bolt I installed into it. Now if my FA is indeed bad and a new item would raise delivery and pressure I'm going to have to lower the pressure again on the WUR. This will be fine with me and I'm pretty sure I'll manage that part.

Well Tony, I know you like us that struggle with our CIS to test the items to assess they're defective before replacing them. And so I just did!

I found this post of yours and did just that. I put the FA in a glass of water. Blocked one passage and put my hand pump on the other and sure enough bubbles came out of the bottom at 15 inHG and if my memory serves me well that is too low. Am I correct that the diaphragm/spring is defective and the FA is leaking?

Test procedure.......
 

Diederick,

The vacuum test for the FUEL ACCUMULATOR is to determine if the rubber membrane or diaphragm is good or defective. If you could produce VACUUM inside the FA, it means it could hold pressure. I don’t know where you got the 15”Hg information(?). Just ignore it.

I could test a FA by simply blowing air by mouth to the partially submerged FA in water as shown in the test set-up. Any sign of air bubbles is an indication of an air leak. Your FA is defective.

If people would only listen and perform the necessary tests in a timely manner, life would be much easier. Why would it take this long for people to do the right thing? Next is to test your maximum delivery pressure. Connect the gauge and test your FP with the valve CLOSED and share your data.

Tony

Thanks Tony. I'll gather the correct fitting (M14?) from my kit to hook up my pressure tester to the fuel line going to the FA. I'll try and go out to my 911 soon, hopefully tomorrow evening. We'll see if it meets the spec of 6.5 bar

Hi Diederick,

didn't followed the thread from last year...but as I read from yesterday and some of the recent postings, I want you to point to this concerning qour questions according the fuel accumulator:

https://forums.pelicanparts.com/porsche-911-technical-forum/1119829-accumulator-pump-check-valve.html#post11704708

I want to encourage you - you made the right steps and I guess you're close to the solution - ok, no wonder - almost everything has been replaced. The thing is - mostly not only one fault is on every not perfect running CIS engine the standard. But the system can hide other faults by "tuning" it on every aspect by the mechanic....mmostly good enough for very much common car drivers....and that's the problem...

To your questions:
1. Will a lower voltage influence the fuel pressure? Of course, the pump does not powers as much with 11volts as it could with 12-14volts. Load the battery asap anmd for further troubleshoot.
2. A leaking fuel injector: Always bad. They're mechanically pressure operated only, this means over the time they will wear out mechanically in starting to leak at lower pressures, so this could be a culprit for a too low fuel pressure. But as I read you already replaced them all? Probably at least one is stil bad? Did changed their position to see if the error wanders together with the injector?
3. Your AAR closes in 7 mins - too long for my understanding, 2-4mins max time is ok. Probably it hangs due to dirt, you can flood it (of course electrically disconnected) to clean it, several times if necessary. In general they won't fail mechanically, but as always - nothing is impossible. Does it warms up electrically? Take it out of the car to perform those tests again after cleaning it.
4. You already replaced the fuel pump, very good. Pierburg is also very good, unless you exactly took the right replacement. BUT: The Bosch pumps always ship with a new check valve. Pierburg don't, from what I know. Did you verified the check valve as well? The check valve is as important to a proper fuel pressure in the whole system as the fuel pump and the fuel accumulator do. On my SC I found an emptied check valve (no ball, no spring), so the CIS could not hold the pressure that long. BUT - the pressures it showed wered exactly those given by Porsche/Bosch. And even still the fuel accumulator and the check valve were still bad...
With a new fuel pump, check valve and fuel accumulator, my car now holds a pressure of more than 2,2bar after turning off the engine, and it takes hours to fully drain the pressure (over night), so it surpasses the factory pressure values by far now...the cold and hot start is perfect now!

Here I found a list to compare the Pierburg against the Bosch; remember that this list is not valid for the 930.10/204HP RoW 911 SC!

https://i.imgur.com/81P0X1e.png

Porsche/Bosch numbers for the 180HP 911 SC:
911 608 102 00
911 608 102 02
Bosch 0 580 254 984

Good luck and keep us posted!

Thomas

Hi Thomas,

Thanks for your elaborate reply. I hope I'm near to having the engine run properly. I've invested nearly €2500 in parts and it's unbelievable that the engine still runs worse than when I started with bad rubber seals and gaskets, broken injector sleeves, leaking injectors, incorrectly routed vacuum hoses and the list goes on.

I want to focus on the check valve here because I did a lot of research before purchasing the Pierburg pump. I got the 7.21659.70.0 from the E3T series as they call them. These pumps are supposed to have an internal check valve, see the first paragraph in the left upper corner in the attached screenshot of documentation.

Also, I was quite happy with the way the AAR closed. Mind you it was tested when it came out of the freezer and thus was frozen at -20C.

I'm hoping to test fuel deliver pressure soon and install the FA when it arrives later this week.
https://uploads.tapatalk-cdn.com/202...8b0435b2fe.jpg

I got ill last week so I was out for a few days. In the meantime a nice new silver Bosch fuel accumulator arrived. As well as the M14x1.5 to M12x1.5 fitting to test the check valve. I finally got a chance to go out today.

My conclusion is that (1) the check valves passes the test. A few seconds of the fuel pump on gave over 6 bar of pressure. That slowly dropped to 2 bar and per 5 minutes the pressure dropped 0.05 bar to 1.8 bar after 20 minutes.

http://forums.pelicanparts.com/uploa...1654524133.jpg

And (2) CIS is still fighting me in every possible way. I then spent over an hour to install the fuel accumulator. The main problem was to get the hard line to the filter to seal. I eventually took out the fuel filter and assembled both on the floor. But to no avail. After many attempts I still get a wet fitting.

http://forums.pelicanparts.com/uploa...1654524241.jpg

That would be the center fitting or left in the photo. The one that seems to screw on further than the line from the pump. Am I doing something wrong. Believe me: they are on tight. I removed all the fuel lines several times and none of them leak except for this one.

Also, I let the fuel pump run for a few seconds to check the cold pressure. Unfortunately I was just under 1 bar. I had hoped it to be higher due to the old fuel accumulator losing pressure but OK. I also heard some squeeking injectors. Remember, they are new and did not open at this low pressure before. What is going here?

Well, I slept on it... but it still doesn't make any sense. There are no fiber rings or crush rings missing because there should be none.

I suppose I'd best take the assembly (filter and acc.) out and inspect it on the work bench. I'll check to see if the ball of the hard line is undamaged because that's what's supposed to seat in the accumulator fitting. I did notice the surface was hard to mate especially compared to a cone fitting. The ball seat tends to wiggle.

I'd rather not resort to thread sealant unless anyone would advise me to. I have Permatex PTFE sealant and Loctite 574 at hand. Or I could use some PTFE tape. But I can't see how that should be necessary.

I took the assembly out and to the workbench. It seems the ball seat of the hardline is OK.

https://uploads.tapatalk-cdn.com/202...6737de325a.jpg

But the inlet has a hairline scratch that took me 3 photos to capture but must be the culprit of the leak. Could this be a manufacturing error?

https://uploads.tapatalk-cdn.com/202...77f96de12f.jpg

Wow that’s a tiny scratch!! I’d bet that with some 800 grit you could eliminate it.

Fuel Accumulator.......
 

Diederick,

Did the the new fuel accumulator come like that? The compression fitting of the outlet is not even close to the smoothness of the inlet. I would contact the vendor and show the picture of the fuel accumulator. They might replace it. That is certainly a poor quality merchandise. You would be lucky to make it leak-free.

Tony

Hi Tony, yes it came like this. New Bosch item though sealed in plastic and a Bosch box. I contacted the vendor indeed. Hopefully they'll have good customer service and will replace it.

Just another example of my bad luck with CIS. If it weren't a $180 item I'd place another order right away and get back at it. But I'll wait for their answer first.

I'm a little hesistant to sand the outlet. I wouldn't want to get particles in the FA.

Over thinking.........
 

Diederick,

What ever metallic particles you created fixing the fuel accumulator would be filtered. Blow compressed air to the FA after sanding or position the FA upside down and perform the sanding operation. Wipe clean the fitting and you are done.

Think positive and you could overcome more challenging problems in life. You might as well fix the ball section of the S-tube between the fuel accumulator and fuel filter to improve the sealing and eliminate the leak. Summer is coming very soon and good driving season on your calendar.

Tony

Thanks for your positivity, Tony! I'm off to a father and son evening after work and see Eric Clapton perform tonight. But tomorrow I'll get some 800 grit and sand the ball section of the S tube and outlet of the FA and report back.

2.7 will not run well after CIS rebuild
 

Given how small that scratch is, I don’t think it’ll take much effort to get a nice surface.

You could also use a drill or dremel tool with a conical polishing bit to address the entire surface.

Like Tony said- this is simple and you’ve totally got this!!

Edit: a thought:
Isn’t the FA, port agnostic in that it doesn’t matter which is the input and which is the output? If that’s the case (can’t remember and not at my car to check) then you could flip it to see if indeed that scratch is the culprit or if it’s the female part of the cohline fitting… not sure if that’s more work than just nicking off the scratch but a thought none the less.

I'm late to the discussion and confess I haven't read all the replies but I read your initial post and that all looks good.
Check your timing. Make sure your distributor isn't 180 degrees out of time. That your sensor plate dances makes me think your out of time and intake valves are still open when they should be closed.

Hello one and all! It took me a few days due to busy family life and, if truth be told, it's a little hard sometimes to find the energy to go out for the so manieth time to get the CIS sorted.

However, I put the filter and accumulator assembly back in place after having carefully and meticulously mated the two on the work bench - away from the car. My 911 is not parked at my house so I often go back and forth with parts and tools. When the lines were on and tight I grabbed my remote fuel pump switch, connected the battery, turned the key and flicked the switch.

I heard fuel and pressure building... and an odd whistle. I waited a second or two and at that point fuel came squirting out of the fuel line that runs from the filter to the CSV and FD. F***. The FA kept dry and all seemed well. But now a new issue has risen.

http://forums.pelicanparts.com/uploa...1655148911.jpg

I'm pretty sure I didn't break the line during the dismantling of the filter and accumulator. I admit it's a little stretched and could point to the right rear. But I suppose this was going to happen at some point. This line looks particularly brittle and the rest seem fine. And in that perspective I'm glad it happened now and not while driving.

What's the best next step here? I found it's part number 93011057000 and like $200. Do I have any other options? Should I have the polyamide of my original line replaced?

I got Len Cummings to make me one - mine leaked also after moving it to replace the accumulator.

len.cummings@verizon.net

Forty plus year old fuel lines........
 

Diederick,

I could offer you one of my spare delivery fuel lines but they are old too. Not worth paying the shipping cost across the Atlantic. Just spoke to Len an hour ago and he is very busy.

I am traveling to Europe next month and if you could have Len make the delivery fuel line, I would be more than happy to take it with me and mail it from Barcelona. Len could use the fittings of my fuel lines if needed. Or find someone local with experience.

http://forums.pelicanparts.com/uploa...1655159160.jpg

Or you can have one of my spares for FREE that I will pressure test and mail it to you if you could wait till mid July. Arriving at Barcelona on the 16th. Contact Len Cummings ASAP.

Tony

Not sure if someone mentioned it but you may want to pull the tank out and clean it and replace the screen. I'm doing that right now.

Hi Otto, replacing the tank screen is on my list. However my fuel delivery and flow test were good.

Tony, thanks so much for offering your help. I slept on it and decided to place an order with a Dutch company that sells the fuel line new. I'm hoping to receive the line later this week and test my luck once more.

Critical data.........
 

Diederick,

I don’t know how we missed these data from your initial post (#1). Except for the WCP w/o vac, the CP and [B]WCP w/ vac are OUT OF SPEC for WUR-033. From what control fuel pressure chart/s did you get them from? Have you corrected the fluttering behavior of the AFM arm? Check the cold control pressures versus time at 1 min. intervals until the CCP settles to WCP.

Could you make the motor starts and run for a few seconds before stalling? Where are you now as far as start up? Did you check for unmetered air? Have you verified if the CSV is spraying during initial start? Keep us posted.

Tony

Tony, thanks for being so thorough and I know you troubleshoot many threads at the same time but we're revisiting some bits here. The pressure you quoted are from last year - before Ruben rebuilt my FD and WUR. This rebuild also solved the fluttering AFM arm. I posted the current pressures on page 3 and they are:

Cold pressure is 0.8 @15C
Warm pressure is 3.3 w/o and 3.7 with vacuum.
System pressure is 4.5 bar

I use the following for reference:

http://forums.pelicanparts.com/uploa...1655302860.png

http://forums.pelicanparts.com/uploa...1655302882.jpg

As stated on page 3 cold and warm pressures are a little too far apart. Cold could be higher and warm should be lower. However, I will revisit the pressure test once the fuel line is in place and I'll see if the new FA makes any difference.

Also I mentioned on page 3 that I used my diagnostic leak tester and found no leaks.

My order for a new fuel line got cancelled because it's NLA according to company of the link I posted. So I tried my luck with the local Amsterdam Porsche dealership and they'll have it in the morning - which should be great!

I can start the engine and drive laps in the underground parking garage. My AEM UEGO AFR gauge showed lean AFR when driving 1st gear. Then the engine would stall if I'd rev in neutral after which I would be unable to start the engine. This was all pre FA replacement. I'm hoping to achieve different results after dumping another $400 into the bottomless CIS pit for the FA and fuel line.

Since you had the WUR rebuilt, the enrichment between 3.7 to 3.3 bar is only 0.4 bar (5.8 psi.) and the system pressure is only 4.5 bar/65.3 psi. These values should have been adjusted higher but if you are happy with these numbers, leave them alone.

My interest is how you did the smoke test because many had done the test incorrectly. Without knowing how it was done, there is a likely hood it was not correctly done. But I will give you the benefit of the doubt that it was correctly tested.

Is the engine running satisfactorily now? If NOT, something is not right. So you are back to square one.

Tony

Tony, I purchased a diagnostic smoke tester and hooked it up to the brake booster outlet on the air box. Then I used the assortment of caps and plugs that came with the kit to close off the TB and the 90 deg pipe coming off the AAV. The tester requires 12v and some baby oil and produces enough smoke to find leaks. In the past I found tiny leaks but I sorted those out. I should also note that I purchased a tube of DC high vacuum grease a while back and I smeared it on virtually all gaskets and seals.

Today I picked up my new fuel hose. I replaced the old one. But I couldn't get the banjo fitting at the CSV to seal. Very odd. I used new copper washers and tightened the bolt using my 1/4" ratchet that I use for all the 12mm banjo bolts of the CIS. I'd like to say that I've developed a feel for how tight to go. Plus a 1/4" ratchet is still on the safe side because it doesn't provide too much leverage. Initially I went tight, then tighter but that didn't solve the spillage.

I then wondered whether the CSV or red plastic was giving issues. While taking the CSV off I wondered whether I was going to regret this because it's going to be a pain to put those two Allen bolts back in. I didn't crush or damage the copper washers and the CSV looked fine. The red plastic was still connected to the pipe at the back and I did not dare to take it off so it's staying.

I took the CSV home and hooked it up to a battery. It clicks alright. Sprayed some carb cleaner in and I wouldn't say it sprays but it sorta drips. Actually I have a spare that came with CIS parts some time ago. I tried that one too and it showed similar performance. So I guess the spray is tiny? Not like a modern injector that has a V shaped spray pattern. Am I right? Anyway I'm soaking both overnight in some Liqui Moly diesel cleaner that I have left from when I tried to clean and salvage my old injectors - that was unsuccessful and I currently have new ones installed.

Something I still can't wrap my head around is that right now I randomly hear injectors squeel and open. I haven't run the engine for 2 weeks now or so. So I'm talking while I run the fuel pump and see a cold pressure of around 1 bar. I have new injectors and a rebuilt FD. Why would they stay closed until the prescribed 2.5 bar?