rough start occasionally

[j930]

what should i be looking for on my 84 930? it wint happen every time but occasionally it will start and just seem like its is barley running. idle starts off low and climbs. when it starts correctly the RPMs are around 1400 and come down to 950. when it starts abnormally it will clear itself up after its warmed up. WUR? any thoughts are appreciated

[RarlyL8]

Stick a set of gages on it and see where the cold pressure is. Most likely just needs a slight nudge of the cold pressure plug to bump the pressure down a few pounds.

[mark houghton]

On occasion mine will start from stone cold and "rumble" at maybe 400 rpms for a couple three seconds before settling up in a proper cold idle. I've always attributed it to my fuel accumulator having to "catch up" and get the injectors full fuel delivery. Could be the accumulator, or could be a leaking injector not holding the fuel after shutdown. But 99% of the time she lights right up and idles correctly instantaneously.

[j930]

i went ahead and took a peak at the WUR and its 90 degrees in my garage right now and its almost closed. maybe 3/16 open. i did notice that the hose that connects to the front of the Wur was maybe not clamped super snug. I put it all back together really snug and it cranked right over.

[RarlyL8]

If the hose on the AAV was not tight it could cause these symptoms due to a small intermitant vacuum leak. Clamp it down and see how she does the next few days. It would be great if that is the problem!