A search of the P0335 code shows that it may produce the symptoms you are having.  Noisy tach signals seem to be fairly common with the FiTech systems.  A change in humidity or a change in the position of the tach wire when you did something else, or a loosened connection can cause it to suddenly happen.  If the system does not know the RPM or if the RPM signal is inconsistent the system may/will get confused.  I'd start with the tach signal first and see if that helps.

I just did a google search on "fitech P0335 RPM noise" and it showed links to FiTech as well as a lot of other threads where people had this issue and what they did to solve them.  I don't think it will run right if it doesn't know engine speed.  I don't have one but keep considering this an option for my 1970 F250 as we intend to travel the US after retirement.  It seems like these systems work pretty well - until they don't.

I haven't put a lot of miles on mine but no issues so far.  Had if for 2 years now.   I wonder if its a computer problem.  Mine seemed to a power draw to.  I put a switch in my trunk at the main power that I could shut it off when sitting.  Steve69

I got it fixed - I think.

After your good advice and several calls to FiTech, I discovered I had a stuck injector.  Stuck open, that is.  Replaced it and everything runs great.  It seems better than before.  Started up immediately and runs smoothly at 850 rpm.  Air fuel is right at 13.5.  

While working on it I thought the gas gauge  was going down rather rapidly, but I didn't really think about it since the stuck injector was pouring gas into the venturie.  After starting it, I took a short drive down to the end of the street.  Round trip is about a mile.  On the way back I noticed smoke coming out the back.  Got to the garage and huge clouds of light colored smoke were coming out of both tail pipes.  So much that I am not about to drive it on the street.  During the drive the gauge appeared to go down a little.  An over rich condition can cause it, but the engine is running very good.  Maybe even more power than before.  It's after 5, so everyone is closed.  Maybe you guys can continue to help me with this.  I have not done any fuel tuning since I rebuilt the Stromberg's on my 40 Ford.

Last edited by lowercasesteve (5/24/2018 6:48 PM)

AFR of 10 during idle is extremely rich. A good cruising / idling afr is right around 14, while WOT should be around 11-12. I would do as Don says and check your oil for contamination. Hard to say what the smoke is without seeing it in person.

If you don't mind me asking... What are your thoughts on these type of systems? I still have the standard Autolite 4100 (great carb by the way) and as soon as that starts giving me grief or is in need of a rebuild, I am converting to EFI. I am curious as to how you are finding it.
Thanks.

Changed out the oil and filter.  Lots of gas in the oil.  Where did that come from?  could the rings have been compromised from gas pollution?

Car started right up and ran with no smoke.  Idles right at 850 rpm.  Runs smoothly, but there still lingers some gas smell out of the dip stick.  Probably left over from before.  I think I will run it a few more miles and change the oil again, just to be safe.

Thanks for your help - all.