question about knock sensor wires?

JDM CRESS

New Member
Jun 29, 2005
80
0
0
brooklyn, ny
i was on the phone earlier with the guy doing my harness. good news he got the body plugs i sent him and he is now ready to sit down 1 afternoon to do my harness.

i mentioned the knock sensor wires to him and asked him about redoing them with 2.0 usb shielded wire like what was advised for the wiring on here. he told me he's just gonna check to see if the knock sensor wires have any breaks in them, and that its alot of work to replace them. he said once theres no breaks in the wire im ok.

is it really ok? i really dont wanna have that problem that other guys have. cuz im sure this knock sensor thing is really overlooked with alot of 1jz owners. so should i just let him do what he has to do, or tell him to do those wires over for me??? i do trust the guy, hes very well known when it comes to wiring up cars, especially cressidas! but at the same im tryin to make him aware of the internet sources "THANK YOU SUPRAFORUMS/SUPRAMANIA".

let me know what you guys think about this.

thanks,

daniel
 

suprastanger507mgte

2x88+2x89+1x91+2x92=ME
Apr 5, 2005
3,148
6
38
Hayward , Ca
Man if the wiring loom is already out of the car, it cannot be that much more work.
Looking at what difference wiring the knock sensors have made for other guys, i'd difinetely ask him to do it..
 

T701jz

3M ENGINEER - R.&.D
Jul 23, 2005
657
0
0
Santa Clarita Ca.
Why even bother if you're going to mod this engine any way. One way or another you will need to use a FCD to bypass the knock sensor. The MR2
Has the same problem with the knock sensors and they end up using a FCD.
I think it's better not to full around with the factory harness, that's MO.
 

zoonwen

1JZ Supra
Apr 27, 2005
199
0
0
42
Denton, TX
just rewire them, my wires looked fine also but still threw a code and went away with 2.0 usb cable. Its actually not that hard to rewire them with the swap in. I was able to reach both sensor connectors, but the reach was very tight. I located the sensors with a flashlight then had to feel my way to them with my hands.
 

JDM CRESS

New Member
Jun 29, 2005
80
0
0
brooklyn, ny
zoonwen said:
just rewire them, my wires looked fine also but still threw a code and went away with 2.0 usb cable. Its actually not that hard to rewire them with the swap in. I was able to reach both sensor connectors, but the reach was very tight. I located the sensors with a flashlight then had to feel my way to them with my hands.

so you ran the usb cable outside of the wire loom?

this would mean i wouldnt have to go in the harness if i wanted to rewire them, that i would just have to run another wire from the knock sensors to the ecu???
 
I

itr206

Guest
Why even touch the knock wires?
We didnt touch anything with mine.
We cut the wires right before the ECU plugs and extended them there. Made life much easier and went alot quicker
 

JDM CRESS

New Member
Jun 29, 2005
80
0
0
brooklyn, ny
itr206 said:
Why even touch the knock wires?
We didnt touch anything with mine.
We cut the wires right before the ECU plugs and extended them there. Made life much easier and went alot quicker

yea that does sound quick and easy.
 
I

itr206

Guest
Saves you headache of messing with the knock wires and screwing them up too.
Its obvious mine runs well the way we did it.
 

zoonwen

1JZ Supra
Apr 27, 2005
199
0
0
42
Denton, TX
I just left the cut wire in the loom, you could just extend it with out rewireing it but anyone who knows anything about 1jz swaps would suggest you rewire them because they will wear out eventually anyways.
 
I

itr206

Guest
Why would the wire wear out?
I dunno. i dont see doing extra work for no reason.
 

935motorsports

Active Member
Mar 30, 2005
2,569
0
36
47
San Diego, CA
If you are extending a harness, the stock harness already has shielding which connects to ground points in the harness. If you extend from the ECU connectors, you will not be touching the shielding and because of this it is not an issue.

I recently pulled apart a harness to verify this and about 12 inches back there is the shielding, already there for you.
 

suprra_girl

7M POWAH! ;)
Mar 30, 2005
1,776
1
0
Auckland, New Zealand
www.supra.co.nz
T701jz said:
Why even bother if you're going to mod this engine any way. One way or another you will need to use a FCD to bypass the knock sensor. The MR2
Has the same problem with the knock sensors and they end up using a FCD.
I think it's better not to full around with the factory harness, that's MO.

am i the only one that has found this post strange!?
 

T701jz

3M ENGINEER - R.&.D
Jul 23, 2005
657
0
0
Santa Clarita Ca.
am i the only one that has found this post strange!?

Quote:
Originally Posted by JDM CRESS
your not the only one.

but hey, what do i know? im the one who asked the question.


suprastranger
I have had weird posts in my threads as well lol
________________________________________________

I'm sorry if you find this post strange. But, I understand. So once you have a running 1j or own one, you will come to realize that this post was not so strange at all.
 

T701jz

3M ENGINEER - R.&.D
Jul 23, 2005
657
0
0
Santa Clarita Ca.
For the past months now my self and my mechanic are doing all sorts of RND test with this engine before we move on to a bigger upgrade. So we don't add or contribute any more symptoms to the engine. During our test we encountered a few problems that even Mike Urbano was puzzled about the symptom that were experiencing. The knock sensor might seem to be functioning ok with out sending any alarm indication, but it was enough to send a fuel cut at the higher rate of boost. We believe that the knock sensor was picking up some kind of noise to the system, so we decided to install an fcd and the problem went away. Yes, we also install a boost cut/d before we install the fcd. We are currently in the process of installing a Allen Bradley control module/processor to the system to detect few other things we want to see what's going on in the engine (mechanical and electrical). There are a lot of things that we don't know about what really these sensors are program to do in the ECU more then we think we know.
 
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devil358

in ur sink
Apr 6, 2005
106
0
0
Richmond, VA
wow....really old post....lol....I searched...and look what I went and did....revived an old post...lol

quick question....

If then check engine light is on for the knock sensor, then it means there is a break in the circuit or something like that. So that would make the car go into an open loop mode (or is it closed loop....I forget which one) and wouldn't this make the car pull timing and not drive well?

I just finished my swap and instantly got a code 52, so I have the intention of just going ahead and rewiring the sensors. When I had this on my 7M it would run like crap when you went into boost cuz it was pulling so much timing, but out of boost drove fine. My 1J is doing the same thing.

Would it be correct in assuming that is what is going on? or am I completely insane? lol....

Once I get the knock sensors rewired, the car shouldn't pull so much timing and fall on it's face when it goes into boost.

Correct?
 

Ken

New Member
Apr 6, 2005
350
0
0
42
Houston, TX
you're right. i was getting a code 52 a few weeks after my swap. Car was dragging total ass, it felt like the exhaust was welded shut.

After rewiring it was a totally different car.