In Reply to: Re: How to tell if your fuel pressure regulator is posted by Paul H. on April 03, 2000 at 02:59:31:
: As far as I understand, the O2 sensor, when unplugged caused the DME to enter an open loop state, which slightly enriches the mixture.
: Just as an experiment, try plugging the hose from the carbon canister to the inlet manifold. I have long been suspicious that this may be contributing to a similar hesistation condition on my '91 535i 5spd.
: I experimented with this recently, and am convinced that drivability improved. I have now installed a "restrictor" orifice in the hose, which allows the canister to be purged, but in a limited way.
: I have an electric purge valve, but don't know what is correct operation for it. I do know that it operates, in a pulsed manner, all the time. I'd have thought that it should be not operating at high manifold vacuum ie. idle and part throttle.
: Anyway, food for thought.
Paul, I tried what you suggested. I can not notice any change in idle quality when removing (& plugging the vacuum line to the FR. On, Off, on, off not change. I did remove the purge valve & plugged it. Drove around the block and could not tell much difference. With or without the FR hooked up. Any other suggestions?
BTW, the purge valve doe pulsate about 1-2 times a second
Thanks, Richard V.