Ugh... Another knock Sensor gone

S1cTech · 11-07-2009, 04:08 AM

wow, So I noticed how bad my car was as of late. Got soooo slow. I had a hard time spinning the tires with clutch engaged. lol and my 1st gear pulls in the bottom end felt like I was taking off in 2nd.

I am not sure if a knocksensor would cause that much of an issue but I guess inconjuction with a possible misfire hesitation I am getting when I double tap the throttle at 60mph.

Did a scan. Came up with the Knocksensor again(less then a year I replaced it) Tested one of the old ones. It was reading ohm levels but I am not sure what are good numbers. Anyone kno what is a good ohm level? And what causes these to go so much? I been tearing through my wallet with 91 and up forever just because I know it is the best to use anyway and cleanest but I thought my knocksensor would acutally live longer. lol

smai555 · 11-07-2009, 04:21 AM

i dont know what it should ohm out at perhaps you should check the wiring ... i always get my codes and clear them out to see if they come back, if they do then i will check wiring and sensors .. what brand knock sensor did you get?

chillin014 · 11-07-2009, 08:01 AM

An extra few dollars a tank is "tearing through your wallet" ?? lol. Anyway, my car sounds like yours...extremely underpowered. And I did the resistor-mod as well.

Haynes manual says just to check for continuity between the knock sensor terminals. I forget the resistance necessary but Haynes says "10 M ohms"

smai555 · 11-07-2009, 12:15 PM

Quote:

Originally Posted by chillin014

An extra few dollars a tank is "tearing through your wallet" ?? lol. Anyway, my car sounds like yours...extremely underpowered. And I did the resistor-mod as well.

Haynes manual says just to check for continuity between the knock sensor terminals. I forget the resistance necessary but Haynes says "10 M ohms"

whats the resistor mod? do u replace the knock sensor with a resistor? that sounds dangerous .....

HandsonMaxima. · 11-07-2009, 02:29 PM

it is dangerous, you become the cars knock sensor, its should be only used for short periods of time.

you replace the knock sensor with a 470k ohm resistor to fool the ecu into thinking everything is fine and dandy.

and yeah, i understand about the 91, but then i got hit with the recession and, bam, down to 89, sometimes 87!

chillin014 · 11-07-2009, 02:39 PM

It may be dangerous in theory but I personally don't worry about it. If I could depend on the technology to work right I'd leave it be but I'm tired of having a powerless car. I've never thought twice about running anything but 93.
Unfortunately, I dont think the stupid *** resistor mod is working anyways since apparently it can still detect knock (so i've read)

mahanddeem · 11-07-2009, 07:07 PM

Cheap KS go bad pretty quickly...that's why it's best to have the OEM.......

S1cTech · 11-08-2009, 08:48 AM

Quote:

Originally Posted by chillin014

An extra few dollars a tank is "tearing through your wallet" ?? lol. Anyway, my car sounds like yours...extremely underpowered. And I did the resistor-mod as well.

Haynes manual says just to check for continuity between the knock sensor terminals. I forget the resistance necessary but Haynes says "10 M ohms"

lol well its not tearing through my wallet but $10 or so bucks extra per a tank and it doesn't save my knocksensor what is the point other then cleaner nicer smelling gas? lol. I am still always gonna put in 91 regardless but I been putting in 93 mainly for my knocksensor so she stayed happy. And it was used OEM.

99BlackMaxMS · 11-08-2009, 11:26 AM

Quote:

Originally Posted by S1cTech

lol well its not tearing through my wallet but $10 or so bucks extra per a tank and it doesn't save my knocksensor what is the point other then cleaner nicer smelling gas? lol. I am still always gonna put in 91 regardless but I been putting in 93 mainly for my knocksensor so she stayed happy. And it was used OEM.

Wow, I really don't understand people who complain about filling with 93, it sucks but its really not that much more money. Even if premium is 25 cents more than regular (which it is in most places), its only an extra $4.25 if you fill from when the gas light comes on (17 gal), so I don't know where you are filling up that it would be a $10 difference.

Anyways, about your knock sensor, were there any other codes with the knock sensor? 99% of the time I get the knock sensor code when I throw anything (O2 sensor, misfire, etc). If your check engine light is on, it is most likely not your KS and whatever the other code is. And was the knock sensor that you replaced OEM?

StickShiftV6 · 11-08-2009, 12:41 PM

I used a cheap e-bay knock sensor that was supposed to be oem a few years ago and had the same problem, replaced it with one from the nissan dealer and haven't had any problems yet.

njmaxseltd · 11-09-2009, 07:26 AM

The KS cannot feel the type of gas you put in your car. It's go nothing to do with fuel. It only reacts to engine knock and chances are your engine isn't knocking just because you use 87 or 89 in your tank.

S1cTech · 11-10-2009, 12:04 AM

Quote:

Originally Posted by 99BlackMaxMS

Wow, I really don't understand people who complain about filling with 93, it sucks but its really not that much more money. Even if premium is 25 cents more than regular (which it is in most places), its only an extra $4.25 if you fill from when the gas light comes on (17 gal), so I don't know where you are filling up that it would be a $10 difference.

Anyways, about your knock sensor, were there any other codes with the knock sensor? 99% of the time I get the knock sensor code when I throw anything (O2 sensor, misfire, etc). If your check engine light is on, it is most likely not your KS and whatever the other code is. And was the knock sensor that you replaced OEM?

Yes. OEM.

Yes, I feel like she is misfiring and low on the bottom end

I think my MAF is messsed up too.

Yes there are other SES lights like t he EGR valve that been there for like 3 years. lol

S1cTech · 11-10-2009, 12:05 AM

Quote:

Originally Posted by njmaxseltd

The KS cannot feel the type of gas you put in your car. It's go nothing to do with fuel. It only reacts to engine knock and chances are your engine isn't knocking just because you use 87 or 89 in your tank.

ah ,yes. I know that. but if their knock. IT senses it, And lower Octane gas usually can cause knock.

cashoit · 11-10-2009, 06:18 AM

Hold on a sec....I got the cheap bay sensor and no problems (granted its only been maybe a month since i changed it) .Only cost me 30 bucks..Isnt the OEM from dealer like 200 bucks?? I saw it at autozone for at least a 100 bucks.

Either way...why are ppl using resistors??? Spend some cash, hit up ebay, and replace the sensor. Its easy to do.

And knock is imprecise firing of the engine. Using lower grade gas will make the firing inside your cylinders less potent but not cause knock. Low grade COULD contribute to knock but so cant higher grade. It depends at what precise moment the engine is mis-firing and fine tuning to find which grade is best suited for YOUR car. depending on the condition of the spark plugs and what air intake modifications made to the car u may actually need 89.

My advice, use fuel injection cleaner regularly, and replace the KS. SEARCH, many ppl have used the Cheapbays and they work jus fine.

f550maranello2 · 11-11-2009, 10:01 AM

Quote:

Originally Posted by cashoit

Either way...why are ppl using resistors??? Spend some cash, hit up ebay, and replace the sensor. Its easy to do.

I use a resistor, there is nothing wrong with using it and putting in 93 octane. basically what you are doing it eliminating the sensor...