I have a problem with trying to figure out what could be causing the service engine light soon to come on. When I first drive my X it runs fine, but when I park it and turn it off for about 15 minutes and then restart it, it runs like its missing. The light starts to blink. It misses for about a minute then runs fine but the light stays on. I took it to have the codes read and it said P0302 # 2 cylinder misfire and P0328 Knock sensor High input BK 1. I have changed the plugs,wire distributor cap and rotor cap. After the codes are cleared. Still having the same problem. Same codes appear. Could this be a injector or knock sensor problem? I know its a big job to change out the knock sensor but i can do it. Just need to know if that's the problem. HELP! PLEASE!

First we need a little more info on your X. Year, engine, mileage, S/C or N/A. All this can be factors.

I will say, without the rest of the info, that it does sound like an injector or possibly a fuel pressure problem. I doubt it's knock sensor for 2 reasons. 1) A knock sensor would not retard timing on startup and then clear. 2) Knock sensors don't throw SES lights, only stored codes. Try using a scanner that has "freeze frame". That will show you all the parameters when it throws the code.

Jeff!

Jeff, thanks for the reply. My x is a 2002 with 118000 miles. 3.3 non supercharged. v6. I did have the codes cleared. With the ignition on and without starting the engine i checked the codes again and it came up P0328 knock sensor high input BNK1. How can that be if the engine was never started after the codes were cleared? I will try a scanner with "freeze frame". Thank you for the info. James

at that many miles, have you had the timing belt replace yet, that should have been done at either 7 years or 105K miles. also the knock sensor code doesnt mean anything on the NON Supercharged models.

Yes I changed the timing belt along with the water pump and front oil seal at 110k miles. Right after I bought the xterra. Was running fine til I ran 3 tanks of gas from Circle K in it. Then the problem started. Chevron from now on. Got good spark and fuel pressure, and compression. going to swap the fuel injector on # 2 with # 1 and see if I get the misfire on the # 1 cylinder.

well if you feel it could have been caused from a fill up at a station, then run out as much as you can, fill up elsewhere and do a full SeaFoam treatment on it.

The missfire on #2 just could have been caused by the fuel, try the seafoam treatment first, might save you some work.

Well changed the # 2 fuel injector and is running good so far. Haven't had a misfire on that
cylinder. Time will tell. Thanks everyone for the input. I appreciate it. James

Why not use Launch? It is very useful to Diagnostics
Faults