How To Diagnose And Fix Your Porsche C.I.S Fuel Injection System

The C.I.S Porsche engine is great if it is running well. We find a big difference between running and running well. In this lesson, we take a look at an engine we just rebuilt. We left the fuel distributor and the warm-up regulator as is to test them before deciding if they needed a repair.
Lucky for you they both had issues. We work through the process, and with a little more time in the car, we can get this engine bedded in and running well for a long life.
This is a long video, and you may want to watch it a few times to pin down your problems.
The must-have is a pressure gauge. The light is a bonus, but another harder to get must-have is the gas analyzer. Maybe you could take it to a shop with one.
We still have some tuning to do and will grab more footage. As well as the restoration of the C.I.S system lesson. We are editing that one now!

Noid Light
Fuel pressure test kit
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[julianbaumgartner]

An absolute must-watch for any Porsche CIS owner. Very well done and extremely clear.

[charleseckberg]

Another extremely informative installment.
This Porsche content is by far the best available on YouTube

[georgesbottoli]

c est la premiere fois que je vois une explication sur kjetronic aussi parfaite

[GarageBiljon]

Excellent video! I know how CIS works, but still watched the whole clip as you explain it so well.

[johndoherty]

I am new to Porsche with a well-worn ‘77 911S. This and your other CIS videos opened the book for me. Excellent instructional videos.

[kazstrankowski]

Best video I've seen on CIS diagnostics so far!

[michaelboyd]

Kurt, Your video is excellent!…Reading about how these components work is one thing however, seeing the engine outside the obstructions of an car with the various components and watching and listening to your very clear explanations is ideal!…Great job!!

[aqa]

This is such a fantastic video. Thank you for breaking down the CIS system so clearly and logically.

[evank.]

Thanks for the in-depth video. I now know how to track down the 1 cylinder that keeps popping. 👍🏻

[commanderjoe]

Awesome video, Great explanation! Thank you for taking your time to make this. Also shoutout to the camera guy.

[corym]

Excellent information and diagnosis process. This gives me a much better understanding of the system. Thank you!

[gavintookey]

This video is so informative and helpful. Thank you from an owner of a Lotus Esprit with CIS.

[shabbytiger]

Absolutely fantastic and though explanation. I have a 6 cyl Mercedes with a M110 engine and this session is highly appropriate.

[deniscollins]

Well done one of the most informative videos of all time.

[MECHANISMSSEE]

What an ACE !! I ditched my CIS and running 40 IDA Webers but still have CIS on my VW rabbit pickup so this in a great insight. Thank You.

[adanponce]

By far the best instructional video. Thank you Sir

[KayleighTenny]

Great information, I have a Mercedes 500 slc with a few problems after not using it for a while. Have removed the WUR and ordered a new repair kit. I do wish I had watched this video first ! Have brought the same gauges you use, but didn't realise I could check everything, without the engine running. I may put the unit back together and check, before rebuilding. Thank you for a great video, I will watch the rest now

[stevenb]

Well filmed, narrated and crystal clear instructions make this the best instructional CIS video I have seen. One question, my 74 Fuel Distributor has a banjo fitting with an additional fuel line running to the primary pressure regulator ? Not seen on your set up. I assume that line needs to remain in the test loop, correct ? And does that component have its own test procedure ?

[dennisspors]

Sudden problems with a part of the CIS system. When warm the 76 911s won't idle when warm. No problem with start-up but as it gets warm the rpm drops and then when operating temp is reached, there is no idle. It also runs rough with a few pops. The fuel system (pump, and lines were replaced about four months ago and it worked great. The problem started when the idle dropped a few 100 rpm when warm. Then after a few drives, it will not idle at all. I am thinking there may be a leak (hose) at the warmup regulator? The box and pop-off valve are in great shape with no cracks.

[paulashenden]

great intuitive video on your Porsche engine..