CEL and Knock sensor

Tleg93 · Post by **Tleg93** » Mon Aug 02, 2004 3:00 pm

My L has a strange thing going on and I was hoping someone may have had some experience with this issue. My CEL light is on and off intermittently. I checked the codes and it's the Knock sensor that's giving the false reading. My understanding is that the Knock sensor adjusts engine timing to help prevent detonation. Why would it throw a CEL code and then not throw one? The CEL goes on and off. The car was sitting for a while, maybe that has something to do with it? I don't know.

entirelyturbo · Post by **entirelyturbo** » Mon Aug 02, 2004 3:12 pm

Because the original sensors were prone to cracking, so if it comes loose for some reason, it might open the circuit and throw the CEL. Find the sensor (on the block under the place where the throttle cable attaches to the throttle body) and see what color connector you have. If it's grey, replace it. It's like $30 from www.subaruparts.com search knock sensor some more and you'll find the part number. The new one will have a white connector, meaning it's the updated one.

Tleg93 · Post by **Tleg93** » Mon Aug 02, 2004 3:36 pm

Right on, the Subaru dealer near me wants 64.00 usd for the part. I'll check that link out and get it from there. Oh, thanks!!!

sullione · Post by **sullione** » Mon Aug 02, 2004 6:21 pm

Yeah, I paid about $38 including shipping about two weeks ago from www.subaruparts.com. This should be changed anyway if it's not an updated one because it really henders the car with the old one. I love the way my car pulls now. No more hesitation!

legacy92ej22t · Post by **legacy92ej22t** » Mon Aug 02, 2004 6:23 pm

Hey Scott, if you get a new one I can help you put it in. It's a bitch working down in the pit of dispair....

sullione · Post by **sullione** » Mon Aug 02, 2004 6:36 pm

Why isn't there anyone here to help me? Someone needs to move down here so I can say "I need to swap this or change that" and the can say "no problem, I'll help you".

Tleg93 · Post by **Tleg93** » Mon Aug 02, 2004 6:52 pm

I'd help you out if I could for what it's worth. We could all use help from time to time. It makes working on the cars as fun as it can be. I knew Matt before I came to this board. I guess you could say he 'turned me on' to it. (I'm not gonna tune in or drop out though).

He, that should be our motto.

"Turn on, tune up and drop in" or something like that.

entirelyturbo · Post by **entirelyturbo** » Tue Aug 03, 2004 1:00 am

It's not hard. But before you touch anything, be 100% sure you have a magnet reacher thingie, because you will almost inevitably drop something (probably the bolt) that will be completely out of reach of your hand, but maybe you can get it with the magnet.

legacy92ej22t · Post by **legacy92ej22t** » Tue Aug 03, 2004 1:33 am

Ya, I have one of those long, flexible claw things. It's like 2 1/2' long and has a button on the end that when you push it a 4 fingered grabber thing extends out the end. Then when you let off the button it retracts and closes. It's really handy. I like the magnet ones too and they're better then the claw for some things. When I did my knock sensor though I actually used it to thread the bolt back into the block, try that with a magnet!

legacy92ej22t · Post by **legacy92ej22t** » Tue Aug 03, 2004 1:50 am

sullione wrote:Why isn't there anyone here to help me? Someone needs to move down here so I can say "I need to swap this or change that" and the can say "no problem, I'll help you".

Ya, I'd help too if you lived closer. The thing with me is that I actually enjoy wrenching on cars. That and it's good karma to help out others with their cars so that when you need help there is someone to help you.

vrg3 · Post by **vrg3** » Tue Aug 03, 2004 2:14 am

legacy92ej22t wrote:Ya, I have one of those long, flexible claw things.

legacy92ej22t wrote:When I did my knock sensor though I actually used it to thread the bolt back into the block, try that with a magnet!

Yeah, I remember using them that way when I changed my intake manifold gaskets. It was so cool -- the tool acted as a universal joint so you could rotate the bolt from far away at a different angle, and also, if you started to crossthread the bolt somehow, the claw would slip rather than allow the bolt to be forced! I was so proud of myself.

The next day I went to the systems manager in my lab, a gearhead who's made a living fixing racecars, racing cars, running garages, and selling cars. I asked him if he'd heard of those claw thingies. He was like, "Yeah, magic fingers. You never used magic fingers before?" I was like, "Sure I have. But I discovered a new use for them!" I explained the new application. He goes, "Every mechanic uses 'em that way! You're just supposed to figure it out on your own; that's why the packaging never mentions it."

THAWA · Post by **THAWA** » Tue Aug 03, 2004 4:22 am

sullione wrote:Why isn't there anyone here to help me? Someone needs to move down here so I can say "I need to swap this or change that" and the can say "no problem, I'll help you".

come up to the bay area or norcal, there's tons of us here

evolutionmovement · Post by **evolutionmovement** » Tue Aug 03, 2004 4:39 am

It's an easy job and my 1993 turbo knock sensor works great on my brother-in-law's OBS. Try not to do it when the engine's hot though, it's a bit like playing a painful version of that board game Operation.

Steve

sullione · Post by **sullione** » Tue Aug 03, 2004 6:38 am

THAWA, one day I will visit the Bay area. I'll be sure to look you guys up. I've wanted to go there since I arrived in California back in 1999.

THAWA · Post by **THAWA** » Tue Aug 03, 2004 6:40 am

we'll be waitin for ya

Tleg93 · Post by **Tleg93** » Tue Aug 03, 2004 1:02 pm

evolutionmovement wrote:It's an easy job and my 1993 turbo knock sensor works great on my brother-in-law's OBS. Try not to do it when the engine's hot though, it's a bit like playing a painful version of that board game Operation.

Steve

Yeah, I remember that.

"Be careful, don't touch the sides. Awww, butterfingers!"

The CEL went off and stayed off. I guess I can put it off for a while. I wonder why that happened.

legacy92ej22t · Post by **legacy92ej22t** » Tue Aug 03, 2004 1:55 pm

Could be it was from moisture. The car did sit for a while. The moisture may have finally completely evaporated.

vrg3 · Post by **vrg3** » Tue Aug 03, 2004 3:48 pm

Take the opportunity while it's dry to smear dielectric grease into the connectors!

Tleg93 · Post by **Tleg93** » Tue Aug 03, 2004 4:46 pm

Will do Vikash. Thanks for the tip.

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CEL and Knock sensor

CEL and Knock sensor