This is my first post and please forgive me if this is a long story but i'm at my wit's end...

October
car is idling rough and gassy, check engine light is on (but has been so for nearly a year without any visible/noticeable symptoms til now).

my volvo guy replaces the following: Mass Airflow Sensor, Oxygen Sensor, Throttle Switch. car runs much smoother but still idling very rich and gassy when sitting at a light or in the driveway. the next morning, after i get the car back, the 'check engine' light comes on... i begin to get nervous, and rightfully so.

2 or 3 weeks later, i replace the battery (car won't start, not even turn over). it's at least a 5 year old battery so i figure what the heck, it probably needs it. new battery gets the car running but by this time, its running a little rougher again especially when starting from cold which by this time of year here in NJ is every morning.

2 days later, on a cold morning, the car is now not starting at all. it turns and turns but doesn't catch and start. i get it towed to my volvo guy again who later that week tells me it's some bosch spark plugs that were bad news all along (platinum, i think). he replaces the plugs, and while he's working on it, rules out a computer problem by actually switching my car's computer with another customer's (same make/model/year)to see if either behaves differently with the other's computer - they do not, therefore the computer is not the problem. he finds a code relating to the coolant temperature sensor and replaces that.

he gets me the car back and asks if i've ever had the fuel filter replaced. i tell him not since i've owned it (5 years nearly) so it's possible that the car has the original fuel filter. he tells me that it would certainly help to have a new fuel filter. i make an appointment to bring the car back to do that.

last tuesday (the day of my appointment) the car won't start again - same symptoms as the last time - turns and turns, not catching. like the plugs are fouled again.

i have the car towed once more to my volvo guy. his theory at this point is that it is the cold start injector (a fifth fuel injector that delivers more fuel to the engine to get a quicker start on cold days). he says if this injector is malfunctioning or not turning off once the engine is started or warmed, this could be the cause of the rich mix.

now we're at yesterday (yes nearly 6 weeks since it all began and the car has been in the shop since last tuesday) and he says the attempt at removing/disabling the Cold Start Injector has no effect on the rich idle condition and he's going to get together with another guy (from another shop) to put their heads together and trace the problem thru the entire fuel delivery system.

so here i am, with quite a few questions, wondering what my next move is, for one. and secondly, wondering if anyone has any ideas what this could be so that i could get involved with my volvo guy and suggest what other experts think might be the problem(s).

if you've gotten this far, thanks. if you have any ideas or comments, thanks especially for that.

regards,

austinpm1