Help!!

I have 3 volvo 850s. My 1994 850 (mileage about 70,000) has started to just plain stop, usually at slower speeds or when it is idling. It always restarts eventually, usually after a few minutes and a lot of honking. It is getting very dangerous. One dealer replaced the fuel pump. That didn't fix the problem. Dealer said they can't pull up the problem code unless it is stalled out when they are looking at it.

Does anyone have any ideas? Temperature sensor or Fuel Pump Relay maybe?? How about crankshaft position sensor (RPM Sensor) or the camshaft postion sensor?

 

I read code 3-1-1. And this is what some guy told me.

"The RPM sensor is dying. A whole bunch of engine and transmission "decisions" are based on the RPM sensor or, as it is otherwise called, the crankshaft position sensor. You can do the resistance measurements but unless it has shorted out it won't tell you anything. It is a hall effect device that creates a pulse as the magnet on the flywheel passes by it. When they wear out the pulse gets weak enough that the ECU/TCU can no longer reliably decide if that was a pulse or not. Eventually the car will digress to a point where it will simply quit for no apparent reason and then start gain. The problem gets worse and worse until it won't run at all. Change the RPM sensor and life will be good.

...Lee"

 

Also check the Cam position sensor. The plug is known to fall apart.