I have the most strange of problems with my 960/S90. As a lifelong Volvo owner, I have been able to tackle most all problems encountered. The really fun one was the replacement of the sensor on the distributer plate on my 740 using JB weld and a rivet gun... worked perfectly after that

well...here goes.

for a couple of years my 960/S90 will hestitate and blow black smoke intermittently. It boggs down and then suddenly lurches with a further press on the gas pedal. NOW, HERE IS THE KICKER, It will do this immediately when I fill the Fuel tank. In other words I can induce the problem by simply filling the gas tank.It will start to sputter and spew black smoke right at the gas station. I have hoped that as time went on it would reveal itself as something that actually disables the car. it has not, but it is quite frustrating. the dealer wants $600-1000 dollars to LOOK at it... could be as high as $2000 according to them, but they dont venture a guess (at least not to me)

It will do this for days, or it may go for weeks without a hitch (or immediately on a full tank). No real link to weather, rain or humidity as far as I can tell. Please help?

Dear kafklatsch,

May this find you well. Have you checked for trouble codes immediately before filling the fuel tank and then immediately thereafter, both before you try to start the engine and then after you start the engine (and it belches black smoke)? If there were something amiss with the vapor canister, I'd guess the system would set a code.

Hope this helps.

Yours faithfully,

Spook

It is a weird one. A few things come to mind that you may have already thought of.

A problem with the evaporation system, this is for the emissions, could you be sucking in fuel directly into the intake system?

A bad fuel pressure regulator, that has caused a similar problem on my car?

A bad fuel injector is leaking down, should show up as a rise in oil level on the dip stick?

A bad coolant temp sensor?

DanR '94 964 342,000 miles (108,000 on the new engine)
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DanR