Rough start after sitting

mjbrox · Post by **mjbrox** » 17 Aug 2010, 11:49

I normally do not drive my 99V70 on the weekend so it will sometimes go from Fri Night till Monday morning with out running.

When it does go this long with out running it starts kinda rough. It turns over and starts just fine but it idles rough for about 10-15 seconds. After that it sounds like there are some tics for about 10 seconds, then it sounds perfect.

Plenty of oil by the way.

Post by **jblackburn** » 17 Aug 2010, 12:08

Mine will do that sometimes if it sits for a while (a few days - a week) without being driven. Do you get a big cloud of blue smoke if you rev it after starting up after the weekend?

mjbrox · Post by **mjbrox** » 17 Aug 2010, 12:38

jablackburn wrote:Mine will do that sometimes if it sits for a while (a few days - a week) without being driven. Do you get a big cloud of blue smoke if you rev it after starting up after the weekend?

No, not that I notice

Post by **jblackburn** » 17 Aug 2010, 13:10

If it's not oil leaking down into the cylinders, your charcoal canister might have fuel in it and causes it to bog down at first start. You can try to disconnect the line from the purge valve into the intake manifold and start it to see if the same thing happens.

Once you get it going, please reconnect that line - fuel vapors in a hot engine compartment = not good.

mjbrox · Post by **mjbrox** » 17 Aug 2010, 13:20

what is that charcoal thing?

I am also getting a CEL light every now and then. I can not remember the code, but my research pointed to vacuum hose leak.

I guess i need to identify and replace all the hoses.

Retired MVS Contributor · Post by **Retired MVS Contributor** » 17 Aug 2010, 13:50

It also might be leaking injectors...Pressure (resting pressure) remains in the system for awhile to prevent vapor lock because the injectors are very hot after a run...If one or more of the infectors is leaking after shutdown, you will have one of two conditions...Either a flooded intake, or, if it has been shut down long enough, a dry fuel rail...Put a pressure gauge on the test fitting on the fuel rail, run it, and observe the pressure...Then shut it down and watch the resting pressure...It will drop, but some pressure, maybe 15 or 20 PSI, should remain for 1/2 hour to 1 hour...If it does not,there is a leak somewhere, most likely the injectors, and possibly the pressure regulator...