1973 1/2 911 T
 

My 1973 1/2 T (CIS injection) starts o.k. and idles for 4 or 5 minutes, then shuts down. It will restart, but, will not keep running. If I let it sit for a couple of hours it will do the same thing. I believe I may have gotten some bad gas previously and I have drained the gas tank and changed the fuel filter. The plugs and the injectors are o.k.

Could the fuel pump be plugged up with dirt , and, is there a way to check it and clean it? Someone suggested it may be a warm up regulator problem. Any help would be greatly appreciated!

There are two tests that can be very instructive on an electric fuel pump ... current draw, and output volume.


My suggestion is to do both immediately after one of your five-minute stalls ...

The current draw should NOT exceed 8 Amps, and the output of the pump should be a minimum of 750 cc in 30 seconds.

I have the same car with the CIS. I use my hand throttle to start even on warm days aftert he car has cooled down. Before, the plastic peice for the handle throttle linkage was broke and it barely held idle on its own. Now greatly improved.

I replaced my warm up regulator as well. If your not using the hand throttle on start up then do so and wait til the car is waremd up til release. If thats not the problem, try getting the pressures checked on the WUR. Check the hose on the idle stabilizer (bell shaped unit just behind and on the left side of the airbox. That could be your problem.

Their is a great CIS checklist under Tech. Notes that you can copy and use as a troubleshooting guide for the CIS. I had to learn the hard way with repleacement of the airbox, cold start valve, WUR, injectors, hand throttle linkage, idle stabilizer, fuel accumulator, etc.

Once the CIS is working properly life is great!!!!

Regards
Bob
73.5T