Replacing Knock Sensor

[Skyliner25]

Ok before I cave in to a mechanic and let them charge me 350 + to have a knock sensor installed, I want to know if there's any thing I can do to cheapen the price first.

My check engine light is on and the problem is suppose to be the knocksensor. I got a replacement and they said in order to put it on they need to replace gaskets as well and this comes to 450 at Merlin, 354 at Midas etc but anyway a high price. Anything I can do to lower the price? What are these gaskets that have to be replaced?

[JustSayGo]

There aren't any gaskets to replace with the Knock Sensor. The gaskets would have a name. Ask them what the name is, and why they need to change them?

[kennydoesit]

The knock sensor is located under the hood, near the front and center part of the engine; under the intake manifold. The intake manifold must have to be moved in order to gain access to the knock sensor. Thus, the high labor cost.

In all honesty, every EVERY 95-98 Nissan Maxima that I've diagnosed and worked on has at least the code 0304 which triggers the check engine symbol; the knock sensor code.

Just diagnosed one today that keeps cutting off, but that's being caused by the MASS AIR FLOW sensor; code 0102.

These Maximas are NOTORIOUS for the knock sensor code, though. Maybe there's a recall campaign somewhere and we can make the dealer fix it for free! Hmm.. Checking..

MASS AIR FLOW sensor: $208(adv)-$488(dealer)
KNOCK SENSOR:$130(advauto)-$150(dealer)

[nissandoc]

altima knock sensors are under the intake manifold and can be reached with the car on a lift, no gaskets and no other parts needed. 12 yrs dealer experience, knock sensor alone will not cause mil to come on. dont let these independent shop fools rip you off.

[Mrbizness1]

Originally Posted by kennydoesit

The knock sensor is located under the hood, near the front and center part of the engine; under the intake manifold. The intake manifold must have to be moved in order to gain access to the knock sensor. Thus, the high labor cost.

In all honesty, every EVERY 95-98 Nissan Maxima that I've diagnosed and worked on has at least the code 0304 which triggers the check engine symbol; the knock sensor code.

Just diagnosed one today that keeps cutting off, but that's being caused by the MASS AIR FLOW sensor; code 0102.

These Maximas are NOTORIOUS for the knock sensor code, though. Maybe there's a recall campaign somewhere and we can make the dealer fix it for free! Hmm.. Checking..

MASS AIR FLOW sensor: $208(adv)-$488(dealer)
KNOCK SENSOR:$130(advauto)-$150(dealer)

This is the Altima board, but just had a knock sensor changed on my maxima
Shop did it in 15 minutes with a extension with a universal. Bought it on ebay for $95.00 Map sensor from dealer $180. perge valve $95.00
What ticks me off is the engine runs clean enough to pass emissions inspection, but if the lights on you automatically fail. Shop cleared the codes and I drove it for 25 miles and the light stayed off until he hooked it up to the inspection machine then the light came on.

[kennydoesit]

There is a procedure to follow in order to clear the codes in a 95 Maxima (other Nissans similar), but the codes cannot be erased by just unplugging the battery. This has to be done from the ECU (turning that screw cntr-clockwise then clockwise).

And yes, I have seen knock sensors set MILs on many Nissans.

Originally Posted by Mrbizness1

This is the Altima board, but just had a knock sensor changed on my maxima
Shop did it in 15 minutes with a extension with a universal. Bought it on ebay for $95.00 Map sensor from dealer $180. perge valve $95.00
What ticks me off is the engine runs clean enough to pass emissions inspection, but if the lights on you automatically fail. Shop cleared the codes and I drove it for 25 miles and the light stayed off until he hooked it up to the inspection machine then the light came on.

[rptorain]

i agree with nissandoc a knock sensor will not make the mil come on you will never even know there is a problem.

[altimavenky]

Hi,
I am new to this forum and am really satisfied with the useful responses. I have a Nissan Altima 96.I got it checked recently as the engine light was glowing. It showed the Oxygen Sensor and the Knock Sensor is bad and the total cost to fix it would be $600. I just let it go as I feel it will not make a difference in the running of the vehicle.(Am I right in my thinking if not please advice which is the best place to get it fixed for a cheaper price as my car has already done 176k miles.)I recently changed the gasket as there was a leak in the intake and now it runs fine.The other problems I have is the AirBag light glows and the driver side door doesnt open with the keys and I have noticed this problem in many of the Nissan Cars.

Thanks,
Venky

[robbie20]

Hi i am new to this sit but i have a 1996 nissan altima and i had just replaced the knock sensor in my car yesterday because that is what the code told me it was but no place would touch it because if the spot it was in ( beside the manifold) so i had to take to a nissan dealer and cost me 527 dollars to be put on but did not fix my problem my problem is that my car will idel normal then low than as it is doing that it will putt and jerk thendie and then after a while i can drive it for a while then it will do the same thing over and over again i have replaced in the last 2 weeks ----- knock sensor..$527 for the part and labor ... spark plugs, spark plug wires, distrbutor cap, rotor, fuel filter , intake manifold gasket that so far is what i have replaced and thinking in may just be coil if anyone has any answers please let me know or advise rlb@kc.rr.com thank you robbie baska

[jserrano]

I would think it is the distributor itself that is probably going bad.

[teleguy11]

The knock sensor can be replaced without removing the intake manifold but you will suffer from cuts on your hand from trying to get a wrench on the mounting bolt. Here is a link to diagnosis and specific replacement instructions of the knock sensor.

www.motorvate.ca/mvp.php/507

I am currently searching for a knock sensor for my 1996 Maxima and have found prices ranging from $43.00(ebay) to $131.00(AdvanceAuto).

IMHO this 3.0l engine is the best V6 ever designed because of its reliability, performance, longevity and ease of general maintenance. BTW...This engine does not have a timing belt or a distributor....It has a timing CHAIN that should not need changing unless an obvious problem is discovered. In addition, there is no distributor on this engine. It is a Coil-over design which means there is a coil at the top of each plug...thus eliminating the need for a distributor.

Hope this helps...

Jerry