Hi,

I have a 99 Ram Van 1500 with a 3.9 L and it has some problems that are baffling me. It all started about 6 months ago when a nut or bolt popped loose in the rear differential causing a grinding noise and disabling the vehicle.

Ever since we repaired the rear differential, the check engine light has been on with a P1899 trouble code. I replaced the the Park/Neutral safety switch and the check engine light came back on. I checked the wiring and everything was fine. I replaced the engine computer and the same trouble code came back.

I confused, can anyone help?

Here are some other symptoms that may or may not be related.

When the van gets up to 55 miles per hour, the ABS light and the brake light come on. Sometimes the brakes will slip a bit on the last few feet of a stop.

The van is stalling at stop lights. It runs fine in park. One the engine is warmed up it doesn't stall.

 

From here it sounds like the tip of the wheel speed sensor on the top of the differential was damaged by the bolt bouncing around inside.