Hey heres' a ??. I just had the exhaust done on my X and all was good until today, when I noticed I was down on power. It feels like maybe a knock sensor went or maybe the fuel filter is shot. It feels like I have a "dead spot" around 1500-3000 rpm range and the the S/C tries to kick in and it doesn't feel as strong as it should. It has 60000 miles on it and have never changed the plugs and/or the fuel filter. Help me out on this one!! Thanks

Go to auto zone and have the codes pulled. Then tell us what you find.

OK...ran daignostic test and found 1 code for the knock sensor..code is p0328 high circuit input. Could this be because of the new exhaust?? It didn't say the the sensor is bad, could it possibly be that I have too much airflow and if so do they make a better knock sensor or should I get a cold air intake to even up the flow coming into the motor??

Oh and also, is it easy to replace the sensor if I have to??

Most likely a bad knock sensor. The nissan engine will not turn on the SES light with just a knock sensor out.

I will see if I can find a writeup on the knock sensor replacement.

You're the best Alpine!! Also..do you think that if I put a cold air intake on it would it even the air flow out??
Thanks

I cant seem to find a good write up on the knock sensor replacement.

In terms of a cold air intake it will improve the performance a hair, or even if you change out to a K&N drop in filter.

You must remove the supercharger and manifold to replace the knock sensor. If Nissan does it you're looking at $750-$1000 P&L to do it. It's a real PITA! Mine just went out too. With a supercharged engine you gotta replace the sensor. The power loss you'e feeling is when the knock sensor goes out it retards the timing and bypasses the blower. The sensor is located on the left bank between cylinders 2 and 4.

A P0328 is a bad knock sensor code

Well then...hi-ho-hi-ho its off to Nissan I go...thank god I have an extended warranty!! Already called to see if it was covered and YES my friends it is!!! Otherwise it was going on the auction block!!LOL Thanks to all that helped me out!!

Do you always feel the power drop? Or does it go away when you shut off the engine and restart it? That's what mine does.

BigE, the power drop occurs after each trip of the sensor. The KS is a one reset sensor. Turn the truck off, it resets. Turn it on and go a few miles and boom, it trips. Then it retards timing and bypasses the blower and gets REALLY bad mileage. The only fix is to replace it. My only question is, could something like a bearing noise from the nose gear on the blower trip the sensor? I've noticed this on mine. I just don't know what comes first. The nose gear noise or sensor trip. If the gear is noisy all the time I could see it tripping the sensor or if the sensor trips and bypass occurs, is the bypass causing the noise?

Why isn't there a recall on this?!?!?

Nissan

Exactly!

Strange thing this morning. Got all the way to work, 18 miles, and the KS never tripped. I had full boost all the way... :rolleyes:

I just don't get it.

Same thing happens to me...when the motor goes through the first heat cycle is runs great, then it starts to happen intermittently, I don't get it.So it's going to the dealer to be looked at.

Hello, I've had this same issue for about 1 year now. I have an 02 with 58,000 on it. I took it in under warranty and dealership replaced the supercharger(parts $1800)and no charge because of powertrain warr. Anyways, tech asked me if I ran anything under 91 octane in it because it would trip the bypass. I always run 93 and had belts changed at 30,000. Nonetheless, I still have the issue. Seems to occur once it has warmed up and between 1800 to 3800 rpms.It's a really bad lag.

We should all print out a letter with how many miles we have, the problem, what's been replaced, the year of our X's, name and address and mail them all together in one big envelope.

I'm glad at least others are having the problem so that we can hopefully find the solution a little easier. I just don't think I can take it in and drop $750 to $1000 right now. A recall would be a lifesaver. The lag is a safety issue if you try to pass or merge in traffic.

a. Parts wear out

b. Sensors wear out, Knock sensor, O2 Sensors, MAF sensor

c. If you buy any vehicle expecting it to last forever and not have to fix something.... get a damn bus pass.

d. The knock sensor wont be recalled it is a maintenance issue, so fix your shit.

Damn Kev.....I detect a little haste in your last post. Most of us can fix our "SHIT" but when you start fixing the same thing over and over again, you start to wonder if its a reliability issue with it.Am I wrong?? :rolleyes:

So, two knock sensors "wearing out" before I get to 40,000 miles is normal? Thanks for the input, now go roll around in your Nissan stock, smartass. :p

I just hate to hear everyone say "OMG my parts broke (wore out) Nissan better do a recall so I dont have to pay".

Knock Sensor every 3 yrs or so seems to be the norm for Nissans. The KS will not throw a code on its own and I bet I can walk up to any nissan that is more than 3 years old and get a voltage code with a code reader on about 40-50% of them.

Nissan Stock HA!!!

Well I did manage to get about 70,000 miles out of my second sensor. I guess I should be thankful. Access to this sensor should have been engineered better for the supercharged engines. But yes Kevin. I will fix my shit. I do think Nissan should do a recall for the supercharged engine to do a refit of the sensor somewhere else on the engine. I also know that would never happen.
What really sucks is that it's not something you can ignore or let go, unless you don't mind having a truck with about 100hp and get 7mpg.

I didn't even get 10,000 miles out of my 2nd sensor. Never had this problem or anything like it with any other vehicle that I have owned. Luckily, I only get the power drop (which isn't always there) and not the big drop in mileage.

Hey Alpine...I just got back from the Nissan dealer and they said that yes their is a knock sensor code but all systems passed and they cleared the code and when I drove it home the same shit happened..loss of power and ran real shitty. In your one post you said sensors wear out...since it started doing it again,do you think the knock sensor is "going bad"? Because I will go back and insist they replace it. Let me know what you think.

I am willing to bet it is a bad sensor. It tripped the code in the computer again on the way home and when you take it back it will be there again.