CIS (w/o Lamba) problems...

IF you are going to send anything CIS related for rebuild, send it to Larry Fletcher (CISTECH) on the www.


NO ONE out there is Better IMO.

And many here would agree.

 

I was head of reaearch at a Federally Approved EPA modify and Test Facility in the early to mid 1980s..thus have more experience screwing around with with cold and hot mixture and running conditions than does 99.9% of thge popilation...reading this...

Simply put, 400i was the easiest Ferrari to make pass, and "burn" as clean in terms of grams per mile, than the 5.0 liter MB sedans and coupes!

It merely takes some time, fastidioius attention to detail, and in my case, the ability to modify the patent for the substrate wash coats better known as: "the Catalyst" wash coat

As a Ca. poster, this is a car uner ARB auspices, thus, all things "must" function as at point of laboratory modify and test procedure of FTP-75 CVS bagged dyno test. The "LA-55" portion of the est is all that really matters, the "shed" is extraneous topic as you'ver deescribed your problem...
firstly-get a PAIR of CIS fuel guages and verify correct and MATCHED function left to right of the cold control pressure, and time decay with metallic strips function to hot control prerssure-this matched figure and an equivalent decay time rate is important-but NOT critical...absolut cold pcontrol pressure is also NOT at all critical for these purposres.
<easure with a tendem pair of digital volt meters-prefer ones with flight recorders, and plot the decay os well as base function of the warm up sensor-also, cap AND PLUG the warm up cold start injector.
verify the control and operational function of the aux air valve.

IS THER AN AUX{"grey market"} "frequency valve still installed on theindividual fuel distibutors-or perhaps a crudely installed dual head attempt at "equalized" presssure ncontol by using a SINGLE "frequency valve" shared by BOTH fuel distributors"-this will lokk like an electric fuel injector which has been plumbed into both the warm upp regulator and the fuel distributor upper or lower comtrol pressure aux port( a USA car will have it directly plumbed between upper and lower chambers on the side of the fuel distributor-thois is the valve which is "buzzing" during operation....in grey karket, frequently it does not buzz until closed loop...it all depends on ther design of the board controlled by the integrator circuit.)

Lastly, you will need to ap;ply BOTH fuel guages to the fuel distributors and observe sytem pressures-that they are exactly equal-at bot ends of opoeration(there are BOSCH kits to shim this function-hot more importante than cold!!!
watch that therre is no sudden pressure loss at cold valve and at Rest pressure...
since nozzles are new, the diagnosis is not too complicated here...PS: 1.2-1.5 % pre cat is as much as you need for fuel...less than 1.2 and it will be doggy, more and all you are doing is washing oil of liner walls...
ciao...

 

try: http://www.cisflowtech.com/

For reference consider Larry the only choice. IMHO

 

Strange...never heard of cold fuel pressure being regarded as irrelevant....

 

I have worked with CIS enough, to never want to do it again, so I don't want to drive away someone who obviously is trying to contribute.

This is how I read it:

 

Oh god.. Bringing me back to the 928... I've found the hot control pressure to be key in he warmup regulator.. If the stupid screen isn't plugged... try some fuel system leaner first.. The industrial kind, the fuel distributor is pretty hardy.. Most issues I've encountered we're warmup regulator and injector related..