Hi,
I have a 99 Pathfinder 4 x 4 XE that now has 195,000 miles on it. I am having a problem. Sometimes when I accelerate the vehicle will jerk for a split second. It appears that it loses power while accelerating for about a 1/2 a second and then catches up so that is where the jerk comes from. Does anyone have any guess as to what might be faulty... the transmission, fuel pump, etc? This never happens while I am coasting. It only happens when I accelerate and it only happens once or twice in a 5-10 mile drive... for now.

There are no odd noises or other symptoms.

There are many things that can cause this. My first piece of advice is get the ECU(the computer) read for faults(any garage can do this for 20-30buck).

The activity you are describing can be caused my many factors, most of which are sensors that connect to the ecu.

When is the last time you had the transmission/differential fluid changed? Mine was doing this, and I changed the rear diff fluid and it stopped.

Jose

OK,
Here is what it ended to be....

The mass air flow sensor was bad ($230 part) and the air intake snorkle ($80 part) on the engine had a hole. The mechanics were amazed that the car started at all with this sensor being bad. They said that the hole in the air intake snorkle actually allowed it to run temporarily and produce the jerk I referred it. When the tapped on this sensor while it was running the pathfinder would shut off. When they put tape over the hole in the snorkle the pathfinder would shut off. So, they replaced both. They normally don't charge for a scan, but they did charge me $40 this time. I find that when something goes wrong with the car, this expensive scan is usually clueless. This time, they had to have the scanner plugged in to the pathfinder while driving it while watching readings while the car jerked. That is how they figured it out. The labor was $108, so it was a total of $457.88.

Any comments?