73 CSi Djet / runnability nightmares (archive)

The complete automotive resource for buyers, sellers, and owners like you.

I bought a 73 CSi over the summer, it is in good condition except for the window mechanisms and a runnability problem that no one can seem to sort out. I'll deal with the windows later, right now I'd like to get it running.

The engine is in good shape with compressions in the 195 - 200 range on all cylinders. Transmission, etc.. all seem strong. The problem occurs during acceleration - the car does not like to rev over 4k rpm. In fact it does not like to go over 4k in neutral. What happens is the engine bogs down, you can take the pedal to the floor and the car will sit at 4k and laugh at you. In neutral you can "blip" it to about 5k but it will fall back to 4.

I took it to a local BMW specalist who did some research and finally zeroed in on the manifold vacuum transmitter. When you pull the hose off the manifold, the car goes rich and will rev in neutral, but I tried to drive it like that and it still bogged down under load. We ended up replacing the vacuum transmitter and the car revs better in neutral but will still bog down most of the time under load. Sometimes, however, it will catch and the car will rev under load and let me tell you, it is a blast to drive. But it is not consistent, even when it does "catch" there is some hesitation (trailer hitching) at the high end of the rev range, about 6k.

Something changed when we replaced the vacuum transmitter, I think we uncovered one problem and ran into another. I think the root cause is in the D-jet somewhere, but I have had no luck finding an expert on this system. I want to keep the D-jet if I can.

The only other idea I have is that the car is running out of spark. The previous owner installed a Pertronix ignition and I read a post somewhere, here I think, from someone who had a hesitation problem and went back to points to cure it. I'd like to try that but I have no schematic to rewire the ignition to take out the Pertronix. Does anyone have a clue as to where to find one or can someone describe the wire run for me?

I'd appreciate any advice you long time coupe owners can give me. The csi owners out there will probably agree with something I read somewhere that fixing a Djet is more art than science. I'm sure some of you have seen this before and can enlighten me with your wisdom.

Questions, comments, or problems, please visit the Roadfly help desk.