strange CIS problem

[914efi]

I have blown out the diaphragm twice on my fuel distributor(same cylinder). Everything in the system seems to be right and I am at a loss as to why this would happen.

One thought was that the check valve in the fuel pump was bad which allowed a surge of pressure to hit the FD. I checked it and the pressure bleeds down overnight to a few PSI. This was just with a gauge on the pump output, not the specific CIS gauge.

Could this be the problem? I also had a hot start issue during the short period before this happened.

I definitely have other problems related to idle fluctaution and the hot start issue mentioned above, but I don't think they are part of this issue.

Thanks for any help

[echrisconnor]

There's a fuel pressure regulator on the fuel distributor which prevents excessive system pressure and bleeds it back to the tank. This may be obstructed on your car, howeer, if you've replaced the diaphram twice, this would be an obvious thing to check when rebuilding the FD. Have you checked this? It's on right side of the FD, and is a little piston with an O ring on the end.

Chris

[914efi]

Yes, it has been checked by the rebuilder each time. I have not removed it myself to make sure that the O-ring is in place. He did mention that those can get lost in the system.