Yet another rough idle post heh

parksah07 · Post by **parksah07** » 28 Oct 2004, 00:23

ok guys, seeing a few rough idle posts here, gonna ask about a 98 v70, when im at a light the car seems to have a note-able vibration, when the cars moving you cant notice anything, i put some STP fuel injector cleaner in it, its been in for a good 40kms and its still having a rough idle, could this be the fuel filter or spark plugs or which?
any help is appreciated, thanks guys

Tsquared · Post by **Tsquared** » 28 Oct 2004, 16:14

How many miles on the V70? How many since spark plug replacement? Plug wire replacement? Distribuator cap replacement? Fuel filter/air filter replacemnet? How are your vacume lines, any crack at the elbows?

parksah07 · Post by **parksah07** » 07 Nov 2004, 23:44

sorry post got pushed down

it has 325k on it, (KM) and im not sure about the above, the rough idle is at a light when im stopped, the second i start moving again its smooth sailing so

a) the car moving cancels out the vibration and im too dumb to notice it
b) it cancels out the fact of a bad spark plug? (un-even firing of pistons?)

i dont see any cracks in the vacumn lines, im real interested in getting a nice cone K&N air filter but i hear its hard to setup

thanks

Tsquared · Post by **Tsquared** » 08 Nov 2004, 18:56

You will be going backwards with a cone style air filter. The Volvo airbox is one of the few designs that maximizes cold air into the intake. If you have a turbo that is severely tweaked you will still flow enough cfm to stay ahead of the other choke points in the system.

By adding a K&N filter to a stock airbox you will notice no differance in performance (it will be nominal via gas milage or on a dyno). The real plus of the K&N is that it is washable and is cost effective if you are going to keep the car for more than 4 years.

1toncrewcab · Post by **1toncrewcab** » 18 Nov 2004, 22:33

My 96 850 had an intermitent rough idle, usually when I first started up, but sometimes when I stopped in traffic. When I finaly got around to looking at it, I found that if I pulled a plug wire off while the engine was running, it would arc through the plug wire boot to the side of the spark plug well. This led me to believe the rubber material was breaking down, so I replaced the wires. Just to verify, I pulled the new wires off with the engine running and there was no arcing. I have not had any problems since then. I don't know if the V70 has the spark plug wells like the 850 engine, don't know a thing about any vovlo but the 850, but maybe this will help.