engine only runs with excessive choke

[Sange]

Hi Everyone - thanks again for your feedback. Let me answer a few of your questions:

1. Timing and advance - I cannot comment on the exact procedure but I double checked that my mechanic optimized this during the initial tune up in the spring and again after installing the electronic conversion kit a few weeks ago and the engine ran solid during our one week trip and we motored for 12 hours.
2. Mechanical vs Electric Fuel Pump- I doubt the electrical pump is going to make a difference as I just had the mechanical pump re-built. Reading a few comments on this forum including Don's feedback from years ago it appears that A4 owners are evenly divided and it's a matter of opinion and preference. From what I've gathered the mechanical pump is designed to pull the fuel and the electric pushes the fuel. If the electric pump doesn't make a difference I'm simply reverting back to the re-built mechanical pump. My preference is to stick with the mechanical but we'll see what happens during Monday's test.
3. Air/fuel mixture has been optimized with both the old carb and the rebuilt carb installed a few days ago. This definitely makes a difference but does not get rid of the hesitation. It is set to run a bit richer
4. Hesitation - only occurs in gear when moving primarily from low throttle to high throttle. Does not occur at the dock when running off the dock lines which is strange to me.
5. Lead additive to fuel - Far stretch and was not suggested that it would fix the problem, just suggested for regular maintenance -I will not be doing this. However, up until now I've been using Startron for the fuel. I will start using MMO effective immediately and sourced some locally here in Ontario yesterday
6. A friend of mine with the same boat C&C30-A4, also had the hesitation issue. He found an issue with the compression and 2 valves sticking. He removed the plugs and applied the MMO to release the valves. He has been treating his fuel and oil with MMO for regular maintenance and it's working for his A4. I also checked the forum and a bunch of videos and everybody seems to swear by the MMO. Sooo, I will be doing the same moving forward effective immediately. I'm also going to buy a compression tester to record the values before and after applying the MMO to quantify the condition and improvement.
7. Fuel Filters - I only have one New primary fuel filter that was installed a few days ago at the same time the rebuilt carb was installed and new fuel lines were installed. I am now going to purchase and install an in-line polishing filter and fuel pressure gauge before the carb as suggested thank you. I will try this first before adding a 3rd and need to investigate this further. Do you have a picture of your set-up with the 3 filters that I can use as a reference?
8. Brand new plugs and wires installed during electronic ignition conversion. Yes they are in the correct firing order
9. Will examine plugs and take pics when I remove them to apply MMO to the valves
10. Re-built carb - The carb was sent out to a specialty carb re-build shop and thats all that they do. I was told that they use a kit and new gaskets so trust this was done correctly. The re-built carb definitely performs much better than the other carb and my choke is now working.
11. Fuel looks clean but I have no idea if there is crud in the fuel tank. How else can I determine this simply?
12. Exhaust system issue - can you please elaborate on the issue I should be looking into?

Thanks again guys. Your feedback and questions have been very helpful and much appreciated!!
Frank