maximaking

iTrader: (1)

OK guys, I got the knowck sensor code from the ecu, did a search and found thhat the know sensor is tested by checking the resistance between the sensor and a known good ground. my reading was dead center of the range for spec. Im not sure if its a bad sensor or not. This seems to be a common problem, I got ~140k miles and I know that this wasn't a one time thing as the light came back on w/the same code after reseting it after a few hours. Could this be bad gas causing the problem? I always use name brand gas except for this time where I went to a small gas station in the country.

Thanks
Todd

munji

I am not positicve if poor gasoline is the direct cause of the problem but I wouldn't be surprised if it were. I ran into a similar problem, I used 89 octane for awhile, got the 304, then switched to 92 which is the best we have in Kansas which is funked up since St. Louis has 93 but that is different story) Anyhow, I changed out my knock sensor after it blew codes at me and now all is well.....I recommend changing it and always running high octane.......

chris j vurnis

Change the knock sensor.
Even if it passes the resistance check, it could still be too sensitive over time.

95Max

Do you have only the knock sensor code?

Posible causes if only knock code:

1)The sensor
2)Running low octane gas
3)Bad gas

Once you get the "good" gas back in the tank clear the codes and see if the code comes back

NmexMAX

iTrader: (22)

My error code went away instantly after I changed it. Maybe the wiring harness.

TooMAX

iTrader: (1)

In addition to the other suggestions here, I'd also clean the two ground wires on the top/front of the manifold.

eskim_77

The engine light just came on with Knock Sensor 0304. Besides this, I have 0504 Automatic Transmission Control Unit, and 0705 EVAP Control Unit. How bad is replacing Knock Sensor? Is it difficult? Hard to reach? Expensive? I can't believe this is happening to my car because I have only 65K miles(1997), and 99%, I use Mobil and Exxon for gas. I can probably counts, I filled up with 89 gas less than 10 times. Anyway changing Knock sensor will cure one of problem, I guess. Do you have part number for knock sensor?
Thanks in advance.

sinewave

So why are you going to replace the knock sensor but not change the Automatic Transmission Control Unit, and EVAP Control Unit? You have an error code for each.

I wouldn't change ANYTHING without investigating further. Remember that the ECU is not TESTING sensors and telling you what's bad, it is just reporting what is being effected by a problem.

To me, three seemingly unrelated error codes indicate something else is going wrong. I would clean battery cables, ground connections, wiring harness connections, etc. For the wiring harness connectors, I would disconnect them one at a time, spray them with CRC Electronics cleaner and reconnect.

If you closely study FSM wiring and connection diagrams, I'll bet you will find at lest one connector that all three of these signal wires share. That's where I would concentrate my search.