I replaced the knock sensor tonight and am amazed about how much power I've gotten back. The car was running terrible with hesitation, practically no power and horrible gas mileage. After resetting the computer and driving around a bit, I was shocked. The knock sensor ghost code is gone as well. Maybe now I can experience the full power of my MEVI as I think my knock sensor had started going out right after installed the MEVI.

Also picked up a Summit RPM switch to replace my flaky Harlan.

 

It's a beaituful thing .. truthfully my knock sensor replacement was my most noticeable "mod" .. sad but true.

 

How long did it take to replace knock sensor? Any big deal? When you say ghost code is that an undefined code? I'm getting light and codes = knock sensor, undefineded and evap.

 

Ghost code = when you're cel light does not come on, but you do have some code there. Typically the knock sensor does not set off the cel light, even though the code is there.

 

At what mileage, does the knock sensor typically require replacement?

 

To define hesitation for me: Was it as if the car accelerated at varying levels of HP but throttle response was good? Or was it that the car just would not go from a stop and it paused momentarily. I have the KS code and the car is doing the first description above. I was thinking clogged EGR valve system....

 

how many miles do u have?

 

I asked the question about when they typically need to be replaced. Not sure if you're addressing this to me or not. I am coming up to 59K with about 80% highway miles overall. The car runs fine. I'm just wondering if the KS normally requires replacement at 80, 90, 100, 110K or whatever.

 

For clarification, I've gone through 2 of them and i have 229k, 10 eyars old. And for those who have hesistaion etc, check the codes, iot could be in thre as a ghost code as nismos14 stated.. And read the stickys for further information on how the knoskc sensor is tied into power delivery/gas mileage etc.

 

So based on your experience, perhaps one could expect to get 100K or so out of a knock sensor, unless age becomes a determining factor rather than mileage, which I kinda doubt.

You're slipping, NmexMAX, no "this thread sucks" notations yet today, but I'm sure they'll follow.

 

Like I said, trying to be nice and help today.

Well, truthfully, the KS could become cracked, just like my first one, and this has a direct relation to age rather than mileage, still related to mileage, but more age .. Check your and see if it's cracked ... But yes, a vague statment could say every 100k.

 

The symptoms I was getting were extreme hesitiation and lack of power throughout the power band. Running in 1st and shifting to 2nd was horrible because of the complete loss of power once hitting 2nd. It was actually getting to be dangerous getting on the freeway. It would also have no power in low end at all. I could barely start from a roll in 2nd gear.

I have 130k on the Maxima. I actually tried to change it a while ago and gave up because I couldn't crack the bolt. I decided this time to try it again and used a flex socket wrench to crack the bolt. This time I was successful. I used a U-Flex 12MM and 18" extension to loosen it the rest of the way. I then used a magnet tool to grab the bolt. Reinstallation was easy. It took me about 10 minutes total. I also removed the green plug to make a little more room. Make sure to reattach it otherwise it'll throw a 1005 code which can be cleared with a reset. Drive it around for a bit when done and clear that ECU code. I found out that MEVI does not make it any harder to replace as it doesn't really change anything from the stock intake.

 

Age, heat and corrosion would effect it more than mileage will.

 

I just replaced mine at 120k - but I think it has been bad for the past 10-20k - I know, I should have checked for codes earlier.

In any case, the KS casing was cracked. I personally think the KS was overtightened at the factory - the bolt was a b**** to break loose - definitely tighter than the spec torque (15-20 ft/lbs IIRC). What was interesting for me is that the resistance checked out ok (both on and off the car), but I kept getting the 0304 code. Once I replaced it, and reset the ECU, the code doesn't repost and I have all sorts of power back.

 

Yeah, mine wasn't cracked, it was just corroded to hell.

 

Mine was cracked also, I'm starting to suspect that alot where over tightened from the factory.

 

Plenty of you have changed this little gem is it a big deal? How long did it take? What to watch out for? My car has the code and poor low end power, other than its fine.

 

Please don't ask that question .. this thread was ok .. but now after that comment

 

Read the stickies.

 

Give me a break, simple question! I can't find in stickies where this is detailed...........

 

From the How-to sticky:
http://forums.maxima.org/showpost.ph...45&postcount=4

 

Cool, that helps thanks.

 

..... If it's not detailed enough, then

Knock Sensor > j00