knock sensor

[kondo]

So I went to get my S-AFC installed and dyno tuned wednesday. There is someting wrong with my car. The last time I had my car dynoed it hit 186hp and 204 ft/lb with the stock pulley, injen intake and greddy evo. I have since uprgaded to a 5.5 psi pulley. Somehow my car was only hitting 186 HP and 185 Ft/LB as a baseline. How the hell did I not gain any Hp and lose torque by raising the boost. After an hour a messing with the S-AFC my car got up to 198 HP and 210 ft/lb. Then on the next run at about 5K rpm my car made some weird noise and the power instanly droped and it ended up only making something like 185 HP. When comparing the AF ratio between the crap run and the run before they were exactly the same. Then we noticed that the check engine light had come on. So the the tuner checked the code and it said it was the knock sensor I don't have the exact code number and explination in front of me right now but WTF. So I ended up cutting my dyno run short because the dyno guy had to go to LA for a show this weekend. But when he gets back he said I can come in when the shop closes and he will screw with my car until he gets the S-AFC dialed in right. So whats up with the knock sensor? I had my SC dealer installed so will they fix it for free if they don't notice that I upgraded my pulley? Or is there a way around this, the dyno guy was saying that I can put some cheap American knock sensor in that is less sensitive and will trick the ECU. Has anyone else had issues with knock sensors? I remember reading about someone who went through a few of them. Also any explination for my loss of HP by upgrading the pulley.
Thanks, I will try to put the code up later if I get a chance.

Nick

[krook]

unfortunately, ryan was right about upgrading the pulley. once you do, it'll most likely blow the knock sensors. do you have the upgraded 2.9 pulley or do you still have your 2.75 pulley on there.

i'm interested in how this will all turn out. i have a 2.7 pulley from pulleyboys waiting to be installed. let us know how it all turns out Nick!

[Yanks0114]

The sensors are pretty expensive so your best bet would be to goto toyota and have them replace it. I'd put the stock pulley back on and have them check over the car because you still should be higher than 186hp. The ECU might also have been retarding timing. I'd stick with the toyota knock sensors because they are free under warranty

[Flipside909]

So whats up with the knock sensor? I had my SC dealer installed so will they fix it for free if they don't notice that I upgraded my pulley? Or is there a way around this, the dyno guy was saying that I can put some cheap American knock sensor in that is less sensitive and will trick the ECU. Has anyone else had issues with knock sensors.

Nick

Knock sensors are probably out. If so, you should notice sluggish performance and some cases the CEL will pop up. They will not fix it for free if they notice the stock pulley. They will probably tell you it's $200 a piece for each sensor...you have 2 of them. Theres no away around this...and theres no such thing as a "cheap American knock sensor". No one has yet found an alternative to the Toyota/Denso made knock sensors. About 70% of the people with S/C's in our club have had knock sensor problems about once...a few twice..and some 3 times. You aren't alone.

[Yanks0114]

They will not fix it for free if they notice the stock pulley.

I'm assuming you meant the upgraded pulley. Chances are they wont notice, but if at all possible put the factory one back on. Its not worth it to risk it, especially if you don't trust any other dealerships then the one you are going to or they other ones are far away.

[Flipside909]

They will not fix it for free if they notice the stock pulley.

I'm assuming you meant the upgraded pulley.

Yes typo, I meant upgraded.

[EricSol]

Guys, with this pisswater 91 octane in CA your lucky to be able to run 4psi. If you wnat more boost you have to lower the compression or pull timing or run race gas.

[kondo]

Here is the code that the guy at the shop pulled P0330, and the explination in his book was "knock sensor bank 2 malfunction". I think I'm going to put the stock pulley back on and take the car to toyota sometime next week if I get a chance. Ill play it off like I don't know what is going on and see if they think it is the knock sensors. If not I want to see if they give me a BS explination. The last time my check engine light went off they said it was caused by a vacume hose leak.
Nick

[Flipside909]

Here is the code that the guy at the shop pulled P0330, and the explination in his book was "knock sensor bank 2 malfunction". I think I'm going to put the stock pulley back on and take the car to toyota sometime next week if I get a chance. Ill play it off like I don't know what is going on and see if they think it is the knock sensors. If not I want to see if they give me a BS explination. The last time my check engine light went off they said it was caused by a vacume hose leak.
Nick

Yeah knock sensor bank 2 is gone. But yes, slap the stock pulley back on and get it checked. If the dealer you take it gives you flack...try the next dealer nearby.

[808Camry]

So wait let me get this straight. Since upgrading to a smaller pulley, most guys have seen knock sensor problems, I guess no way to prevent this but to leave the stock pulley on there?

[chef Solara]

To my understanding,Please correct me if I'm wrong. But the knock sensor is gone because the car is running to lean, Right? At least that's what the toyota guys told me.
My car's check engine light also came on, so i took it in and I had several vacume hose leaks, Also my brake booster is completly shot, Everytime I hit the brake I hear a very loud hiss.
So on monday the booster is getting replaced, and hopefully that will turn off my CEL.

[Flipside909]

To my understanding,Please correct me if I'm wrong. But the knock sensor is gone because the car is running to lean, Right? At least that's what the toyota guys told me.
My car's check engine light also came on, so i took it in and I had several vacume hose leaks, Also my brake booster is completly shot, Everytime I hit the brake I hear a very loud hiss.
So on monday the booster is getting replaced, and hopefully that will turn off my CEL.

No you are correct about running lean. It gets worse the higher the boost...especially if you don't have an S-AFC to assist.

[kondo]

Well today I took my car in to toyota at 8am to get the check engine light issue fixed. After three hours I was told the probleom was fixed, They thought that the vacume hoses were not hooked up correctly because my SC was running at idle. So they got a new diagram from TRD on how to hook up the vacume hoses so that the SC does not run durring idle. So they thought that would fix it. However after driving about 10 miles down the road the check engine light came back on so I went back and waited another four hours. They then told me that both of my knock sensors needed to be replaced along with the wiring harnes, and that they would not cover it under the TRD warrenty because the blown knock sensors were not "supercharger related". They then told me that they would fix it for the low low price of $1020. So I had a talk with the mechanic and he tried to explain how the SC could not blow the knock sensors. I told him that I knew of other people(team SC3) that had similar issues with knock sensors. So he said that he would call TRD on monday and see if they would cover the repairs under warrenty, but he basicly said that they would not. So am I completely screwed? Has anyone else replaced knock sensors themselfs. BTW I had the stock pulley on when they checked the car just in case.

Well I went to the store and bought 2 cases of hamms for $8.88 each and I am going to get trashed and forget about how I wasted 9 hours siting in the toyota waiting room only to find out that the dealersihp is not going to fix my car for free.

Nick

[krook]

bastards. drink up nick hopefully, they'll (TRD) will take care of it. is there not a TSB on that knock sensor? or are the knock sensors only blowing with AFTERMARKET pulleys?

[808Camry]

the knock sensors are blowing with aftermarket pulley's, making me scared to slap on my 5.5 psi pulley