Bones944

Just noticed on my 951 today that it seems to be running "slightly" rough at low rpm's, but smooth after about 2200 rpm's, and especially smooth as it transitions to boost. It has always had a mild vibration from 1900 to 2200, (things buzz in the under radio compartment in this range), but seemed slightly rougher below this range today. Cap and rotor are new, belts, seals etc. Almost feels too rich. It was after dark when I got home from work, so I couldn't pull the plugs, but they are usually a nice light tan color. Car has never used oil, and is usually less than half a quart low between changes. I DO know that new motor mounts are in the immediate future, as it vibrates pretty heavily at idle (especially with the a/c on) Ideas?
TIA

Loki

Try some fuel injection cleaner. I believe the recommended is Chevron with techron(sp?).

Chris

Olli Snellman

How about your plug wires.When next time come home at dark, check out if you can see some extra sparks from the wires.
I wouldn't use any injection cleaner.It's rather cheap to have all of your injectors profesionally cleaned.

Olli
'88 951

Bones944

Must have been bad fuel, it runs fine again now. I would like to track down why I have this mild vibration from 1900 to 2200 RPM. It's mild, but you can feel it, and like I said, misc. junk in the console box rattles at this range. It's imperceptible in neutral, of course. I have noticed that this is the RPM range for 45MPH in fifth, and the range the motor returns to at normal shifting at street speeds ( after every shift, I'm normally in this range). I know I need motor mounts, any other ideas for causes?