I bought a 97SE used a few weeks ago and I tested the ECU tonight (no light on though) hoping to find nothing, yet I got a definite 03 04 (knock) and 07 05 (EVAP control or something). What do I do?!!?

Derek

 

First fix the 0705 code, 0304 is a ghost code and should go away after you fix 0705 and reset the computer.

 

I have read 07 05 could be as simple as tightening or getting a new gas cap. If I do that and then reset the ECU, will the CEL come on if the code is thrown again? I ask because the light is not on and hasnt been since I got it. I thought it'd be smart to go check it hoping for nothing. 03 04 is a ghost code? Ive read is notorious for knock sensor, which sucks. I have used 91 octane since Ive had it, yet I dont know what octane previous owner used. Anyone?

 

I wouldn't freak out just yet -- tighten the gas cap, drive around
for a while -- when you release the gas cap, do you hear the
pressure "hiss"? if you do, it's prolly not the gas cap.

Reset the computer...check back in a week, and a week after that --
if the code is there, then start investigating...

my $0.02,
FLO_BOY

 

I reset the ECU and drove for about 20mins. I then checked it and the 07 05 code went away but the 03 04 remains. My idle is between 500-600...not sure if that matters. Gas mileage isnt too great either using 91 octane (highest available). Is it knock sensor replacement time for sure? Is this something a 17yr old boy can do himself with limited car knowledge? If so, detailed instructions would be great!

 

It's not THAT hard -- unless you have monster hands...

go to my website (look at my profile at the left here) and it shows
you where the sensor is, and what it looks like...website may have
exceeded daily limit, but, give it a try.

you'll certainly need a socket set with a "u-joint" swivel head (forgot the name of it...). The sensor itself is kinda pricey...you'll be pis$ed when you see how small this thing is!

other than that --> SEARCH --> I know for a fact that this will be in here.

FLO_BOY

 

Is it a knock sensor for sure? Could it be o2? Any way to check before I waste the $130+ on knock? I just got this car and was hoping for it to be reliable....so what should i do?

 

I dunno...your car is reliable (or should be)...the Knock Sensor is not. MANY MANY people on here have had to change their knock sensors.

couple things to think about:

-- Does your car feel sluggish? I know you've had the car for only a short time, so, this is a tough one...

-- Reset the ECU...wait...see what happens....

-- give in...replace the sensor.

while you could replace an O2 sensor -- which one would you change?
There are a couple of O2 sensors, so, it would be a crap-shoot to pick one...atleast with the code, you know what sensor to swap.

Not changing your knock sensor (if busted) will give you poor gas mileage and less power as your timing will be retarded (slowed down, not handicapped )

hope this helps.
FLO_BOY

 

Mileage is crappy and at low RPMs acceleration seems sluggish, but thats with no comparison. After reading through 49 pages of search for 'knock sensor' I came across a problem. Im in CA and most likely have a Cali-spec...I have read this has a swirl valve in the way which requires you to take a manifold off...is this true? If so, I think this repair would be too much for me to do...ideas, help, anyone in Bay Area that would do it for cheap or just help me out? Anyone? Thanks!

 

Hey man i just changed my knock sensor yesterday.. its really not that hard if you have small hands.. Or if you a have a girl friend or a little brother with small hands. anyways run a search for "how replace knock sensor" only in the fourth generation forum. there is a post with a link to some detailed instructions... might i add that when you find the knock sensor,,, remove a green sensor clip that is next to it, in order to try to get your hand down under the manafold.. removing the sensor is easy.. its getting the bolt started again that is difficult... if you cant find the link just PM me or email me and ill forward it to you...

 

Any different on a Cali-spec?

 

for a knock sensor, I don't believe so.

-FLO_BOY

 

no there wouldnt be a differance for a cali car,, not on the knock sensor... maybe the O2 sensor...