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Discussion Starter #1
Hello all, I have a 98 type SH and i have error code 23(knock sensor). Next weekend I plan on dropping the ATTS unit to gain access to the knock sensor and replace it. I have been trying to decide if I want to go oem or go autozone or something of the sort. From what I have seen if I get one from a store it may fail early or not work at all. I want to hear different opinions on what I should do. Another question is what car(or engine) can I go to the junk yard pull one from with having to tear a lot from it to get to it.

Also another thing I have looked at is that is if I have a bad knock sensor I should have lack of power under 3k rpm if I remember correctly. I feel like it still pulls hard through the gears. I haven't taken it pass 5k since I don't want to hit VTEC with this error code. So does this mean that its not my knock sensor or am I just misled in my information?
 

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I'm pretty sure if you go to the junkyard you can pull one off basically any B or h series engine and most likely F seires too, they all have the same part number from my experience . On the h22 there just below the intake manifold just above the oil filter iirc, so they are a pita to get out with the engine in the car but real easy if the engine is already pulled which you should be able to find at a junkyard. but I personally would just buy a new OEM sensor.
 

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Buy the right part from Honda and do it right the first time.

All of the aftermarket ones are junk and fail prematurely. There are a few threads on here from members who have cheaped out and had to do the same work twice.

Pay up, get the right part, and cry once. Or, cheap out, get the cheap part, and cry twice when you have to replace it with the part you should have gotten in the first place.
 

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Please for your own sake buy an OEM sensor. they are expensive but trust me you don't want to have to do this again any time soon, especially since you own a type SH. (Replacing a knock sensor on the base model is very simple in comparison.)

If you have skinny arms and small hands you can get back under the manifold (but above the water pipe) from the throttle body side and gain access to it (remove your intake to gain more access). You can also get a socket to loosen and torque the sensor with some wobble extension under the backside of the manifold after you remove the vacuum box that is attached underneath.

I did it this way the last time I replaced mine (very recently), while it only took about an hour this way (nice compared to the time it would take to drop the ATTS), my wrist still hurts from having to bend it in a very awkward position.
 

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Discussion Starter #5
Ok thank you all for your replies. I will bite the bullet and get a new oem one. So does anyone know why I don't experience signs of a bad knock sensor or could it just be something else simple?? Also is it safe to baby it 100-150 miles on the highway to where I will be working on it?

Also is there anything else I would want to do while back there to make sure I don't have to go back there again?
 

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Ok thank you all for your replies. I will bite the bullet and get a new oem one. So does anyone know why I don't experience signs of a bad knock sensor or could it just be something else simple?? Also is it safe to baby it 100-150 miles on the highway to where I will be working on it?

Also is there anything else I would want to do while back there to make sure I don't have to go back there again?
Well the thing is that your knock sensor definitely isn't functioning if your getting the code for it, (There isn't many things that can go wrong in this case... if you look in the manual, the only reasons for this code are 1 bad sensor or 2 the circuit for the sensor is damaged) personally I couldn't notice a major difference in performance for the short time while my knock sensor was inop, but I believe when it has the code the ECM will retard the timing much more than usual as a safegaurd to try and prevent any detonation (which will in turn reduce performance). Normally when the knock sensor is working properly the ECM monitors the signals from the sensor and adjust timing that way, but when its inop, it has nothing to go off of so it goes into a safe mode.

You should be perfectly fine to drive with the bad sensor, you may or may not notice a drop in performance while you do.

As for other stuff to replace... if you're going the route of dropping the ATTS, you will lose some fluid from it when you drop it and remove the axles etc... it takes Honda ATF, I don't remember exactly how much but its not even 2 quarts to fill up when its completely dry. You might as well replace the fluid with fresh fluid since you're going through the hassle.

It might also be a good idea to replace the exhaust gaskets if you really wanted to (you don't have to remove any exhaust pieces to get the ATTS out but I think its easier just to remove the downpipe section with the CAT to give myself more room but its up to you), if you did happen to remove a section of exhaust they will probably work just fine when you reassemble the exhaust but they are circular metal pieces that are designed to crush into place when the hardware is all torqued down and that is how they seal. If you happened to have an exhaust leak after, it wouldn't be too hard to replace them though.

EDIT: Be careful when dropping the ATTS, the sensors on there are incredibly fragile and some of them are almost impossible to replace with the ATTS still mounted on the block. Nothing worse than seeing that ATTS light come on the dash after you've been in that area.
 

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Mine started throwing a code months ago and i still drove the car fine untill i dropped it to the paint shop, it was running pretty shitty though and not a peppy and vtec didn't really feel there as much or maybe it was me. Bought a new one from honda a few weeks ago to replace asap when i'm home since i'm way to OCD for lights on the dash to be on that shouldn't be. Base Model but By the looks of it i will still have to at least remove the oil filter to get at it properly? I took the other one out the same day i took the car to the paint shop but honestly couldn't get it to go back on(just wanted to see how hard it was) so i figured the oil filter needed to come off unless you had 2-3hrs to get lucky with it and mess around trying. even getting it off was a pain!!
 

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Mine started throwing a code months ago and i still drove the car fine untill i dropped it to the paint shop, it was running pretty shitty though and not a peppy and vtec didn't really feel there as much or maybe it was me. Bought a new one from honda a few weeks ago to replace asap when i'm home since i'm way to OCD for lights on the dash to be on that shouldn't be. Base Model but By the looks of it i will still have to at least remove the oil filter to get at it properly? I took the other one out the same day i took the car to the paint shop but honestly couldn't get it to go back on(just wanted to see how hard it was) so i figured the oil filter needed to come off unless you had 2-3hrs to get lucky with it and mess around trying. even getting it off was a pain!!
Just pull off the oil filter, you'll probably have to add some oil after but it gives you more access. A relatively simple job on the base model.
 

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perfect. won't be a issue since in 5 days i go to pick my car up after a 7 grand paint job : ( lol, inclosed trailer right to storage and oil drained and that sensor changed asap so it's ready for next year along with my yearly winter valve adjustment! 230k all original KM on going perfectly strong zero leaks and good compression still....for now haha
 
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