97blackSE

iTrader: (1)

Okay, Here's The DILLY, lol
Well, A while Back, I had The Front Left O2 sensor go on me...Due to a SERIOUS lack of money, I left the sensor for awhile...It was odd tho, the only time the CEL would come on, was when i really got on the car for an extended period of time. (i knew that the O2 sensor was bad, even thought the light wasn't always on, b/c i was getting 17mpg on lucky days) After about a week of having a bad O2 sensor, when the light came on again, i pulled the code to make sure it was still 0303...it was, and 0304 too! I was informed by a friend that the Knock Sensor Code is often just a ghost code... Well i changed the faulty o2 sensor, and BING, 23mpg and no more CEL under any circumstance...However, when i went to reset my ecu after installing new o2, i was still getting 0304! So i reset, and have been driving for about a month now...Then i remebered the code, so i decided to slap the Car into diagnostic again...ALAS, still gettin 0304...! I wonder if i should change it! i mean, i AM getting a consistent 22-23mpg...and my car seems to have plenty of power...i whomped a modded cavalier Z24 the other day like it was no one's business...
I don't understand why i have this lurking code, and no CEL, doesn't make sense...i have found someone selling a brand new Knock sensor for 100...should i just jump on it and change it? HELP ME!

FLO_BOY

you can test your KS...not sure how though

if you don't feel any power issues, then don't change it,
but, if you are continuously getting the code, then it's
not a bad idea to change it...

FLO_BOY

Jamsan

iTrader: (2)

change the biotch

njmaxseltd

iTrader: (19)

The KS code 0304 is set when the KS produces a voltage signal outside the acceptable range.

This may be caused by excessive knock and ping.

Make sure your engine is running right before you change the KS.

High carbon deposits will cause some engine ping on high mileage cars.

The 0304 code that gets constantly set may be telling you something about how your car is running, rather then the sensor itself being the issue.

97blackSE

iTrader: (1)

O.K. well, I just did a whole $hitload of maintenace things...Changed oil, Fuel Filter, O2 sensor, Cleaned Throttle body, and PCV...New Alternator...I'm also about to do my plugs...
I have Just Under 75,000Miles...
Does this tell you anything njmaxseltd?
Kyle
How can I "make sure the car is running right"
before I change my sensor?

FLO_BOY

tells me that you really love your car...hehehe...free bump!
FLO_BOY

97blackSE

iTrader: (1)

Well FLO_BOY, I do, and I am just kinda ****ed, cuz I have done SOOOO many repairs on this car...I will be psyched when they are all sorted out and i can save money for MODS, and not for REPAIRS!

njmaxseltd

iTrader: (19)

It's really hard to say 97, sounds like you've got your maintenance all up to par. Reset it again, drive around going easy on the throttle for a week and see if the code comes back. Play a bit, if you can't get the code to go away for more then a week, replace the sensor.

97blackSE

iTrader: (1)

Will Do!

delacruz_17

iTrader: (1)

To check if ur KS is working, do the following. Disconnect the KS from the harness. Use a Ohm-meter (set to measuring at least 10 M-ohms), check for continuity between the two terminals of the KS connector. If there is an open ciruit then u got a mested up KS buddy it needs to be replaced. For more info on checking and replacing ur KS check out dis site http://www.motorvate.ca/mvp.php/507

95seMax

iTrader: (11)

just change it dont worry
and buy mine when u decide to change it , $100 shipped for NIB Bosch knock sensor, pics on homepage

solar2000

how do you tell if your sensors (any of them) go bad??

DougAtoms

a bit slugish on the low end and sometimes weak starts, ie doesn't start up right away on cold starts, needs a bit of throttle. Many people don't notice the performance drop but usually always notice the performance increase after replacing a bad knock sensor. Replace the sensor, its bad. The diagnostics are correct, trust the ECU. $100 is great price. Use premium gas as required by manual.

KINGMAX

take it out and test it with an ohm meter. Also I replaced my knock sensor awhile back, the only code I was pulling was 0304, I had loss of power and it also seemed kinda bumpy under acceleration. If you reset the ecu the code should come up within 5-10 miles of driving if the sensor is bad. BTW, if you want to replace it without taking apart the intake manifold you need small hands to get in there...unless you have a 95-96 for some reason the upper intake manifold sits up higher than on '97-'99 models and you can easily get to it. Once you get in there there is one bolt that goes throught the center of it into the block, and a single wiring harness that plugs into it. Your best bet is to get the socket on there first and then the wratchet there is only enough room to loosen it one click at a time so be patient. It takes about 9-10 clicks before you can take it off by hand. Good Luck

bananamax

The best thing that you can do is buy a Haynes or Chilton manual. Awesome info inside.

DougAtoms

A factory manual is for serious mechanics and for those who want to get the job done in the most cost effective way. It blows away Chiltons and Haynes. If you want to service your car like a professional, use a professional tool. The payback will occur in the first repair.

Jime

iTrader: (10)

If you really want to know if the KS is working properly or not get or borrow and OBDII reader. It will give you a constant readout of the engine timing. Take it out and do a WOT run in 2nd or 3rd and monitor the timing.

Then, insert a 470k Ohm resisitor in the KS plug. Just disconnect and insert the resisitor across the plug that goes back to the computer.

Take it out again and compare timing readings. If they are the same the KS is ok. If your timing is being pulled back then your KS is bad or you have a knock problem.