Reader Question My 1998 Nissan Pathfinder has approximately 195,000 miles. I just had my timing and drive belts (original) replaced as a preventive measure. Now, my “check engine soon” light has appeared on my dash.
I was told that it was a possible oxygen sensor problem and/or a fuel pressure regulator problem(s). I was told that not enough gas was being distributed on “one” side of the three cylinders and the other side (three cylinders) is functioning properly.
What do you suggest?
Thank you for your attention and assistance. I look forward to your reply.
This light could be on for MANY reasons, a bad oxygen sensor is of course one of them. I would get your on board computer “codes” read by a qualified mechanic and see what is happening. If this light came on IMMEDIATELY after the last repair, I would suspect they have something unplugged, or a wire connection on a sensor is broken or something of that nature.
The timing belt job is a big job on this vehicle and the likelihood that the last repair induced your new problem is pretty high.
I would go back to the timing belt mechanic and ask them to triple check their installation and look under your hood for anything left undone or left loose.
Let them know you are going to get the computer codes read elsewhere and if they say the light is on because of this timing belt installation you will expect these guys to pay your diagnostic fee.
I would only say this IF the check engine light came on immediately after the repair….if it did not, it could be totally unrelated.
Here is more about check engine lights.