Here's my problem, i replaced the head on my '95 420a and upon removing the vacuum hose from the end of the fuel rail and the back of the upper intake manifold the little connection at the end of the hose broke. probably from being old and brittle. well when i put the new hose back on, i noticed that the nipples on the fpr and the back of the intake were different sizes. so i had to get some smaller hose and a coupler to connect two different size hoses. My car runs fine, but takes a few turns of the crank to start up. Is this because the inside diameter of the hose is a bit larger than the factory hose? Will a different size hose make it act differenly?

shouldn't

It could possibly if air is leaking around the nipple. How do you have them connected? Are you using any clamps or zip ties to hold them tight on there?

well first i had one piece connecting the FPR to the intake, but even with the smallest hose clamp i could find it was leaking when i started my car (after installing the head), but now i have a smaller piece that fits tight onto the FPR nipple to a plastic vac hose connector to a larger hose to the intake. But i'm not using any clamps or zip ties cause the hoses fit tight.

Originally posted by ronjeremy525
Will a different size hose make it act differenly?

No.

thanks