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Does this really work, and can it be a permanent fix. I have had a slight stumble for awhile now between 2000-3000 rpms. '96 2.2 5mt new plugs, wires, filters, 02 sensor, clean maf. It feels like the timming is being retarded, ie: lack of fuel. I was really thinking it was a fuel problem but I've been doing a lot of reading abouth this knock sensor problem. So I am wondering how safe/dangerous it would be to relocate it to the clutch bracket thing, for the rest of time?

knocksensor.jpg

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You won't have a cel because the sensor is still conected.

 

However I would look into the possibility that the knock sensor was doing its job when retarding your timing. It does this when a knock/ping is detected. You may not be able to hear it, but the sensor can. May want to try upgrading the fuel grade you use, and put the sensor in it's stock location. And see if that helps.

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Its a common problem of being over-sensitive, so essentially it's not doing its job. The picture is not mine, I haven't relocated yet.

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Well sounds like you've done your research on it. If others haven't reported problems then go for it.

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Provided there aren't other issues with the engine that could be causing knock, it shouldn't harm to relocate it. I wrapped mine in bubble wrap and grounded it with a big alligator clip about 8 months ago and the car is running great. I've been using premium to help reduce chance of knock due to fuel octane being too low.

 

Sometimes combustion chambers and stuff get all coked and carboned up thus effectively increasing the compression ratio. There was an article about this on EndWrench I think. This can cause slight knocking resulting in retarded timing. If you have a scangauge, you could hook that up and see what kind of retard you're getting when you have the issue.

 

Oh, does your knock sensor have a crack in it like this pic (this item should look familiar to one of the posters in this thread...:grin:)

knocksensorcrack1.jpg

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I'm pulling it tom. so we'll see.

 

I've seafoamed it a couple times (intake and fuel), so carbon should be at a minimum.

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Provided there aren't other issues with the engine that could be causing knock, it shouldn't harm to relocate it. I wrapped mine in bubble wrap and grounded it with a big alligator clip about 8 months ago and the car is running great. I've been using premium to help reduce chance of knock due to fuel octane being too low.

 

Sometimes combustion chambers and stuff get all coked and carboned up thus effectively increasing the compression ratio. There was an article about this on EndWrench I think. This can cause slight knocking resulting in retarded timing. If you have a scangauge, you could hook that up and see what kind of retard you're getting when you have the issue.

 

Oh, does your knock sensor have a crack in it like this pic (this item should look familiar to one of the posters in this thread...:grin:)

knocksensorcrack1.jpg

 

I know nothing of which you speak....:grin:

 

If you wanna see a cracked up one, I'll shoot you a pic of the one on the ej22t I'm rebuilding.

 

On a side note, would this relocation be the thing to do if a motor(non turbo variety of course) has a busted up one, but not throwing a code for it?

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That relocation pic looks exactly like how I have my mom's outback set up. Her's has bad piston slap, and it was tripping the knock sensor off, and pulling the timing back to 15degrees.

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since we got the car going back in December. It rattles nonstop, real bad pistonslap. Runs well enough though. we run 89 in it just to be safe.

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So I guess I am pinging. I relocated it, just to actually hear the pinging occur. SOB, I have no idea why it is pinging. It only pings in the 2-3k rpm range, seemed to happen more often when I floored it in 3rd gear, going kinda slow. I don't know what to do. I'll prolly bring it in in a couple weeks. What do you guys think? All possibile tune up items have been done in the past 10k (wires - oem, plugs - ngk vpower, fuel filter, front 02, air filter, pcv, seafoam, tbelt, clutch, and all seals besides HG).

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Here's an article from EndWrench:

Usually low-octane fuel causes pinging, not some problem with the engine or ignition system. While few motorists believe they’ve done something themselves that causes the pinging, if you suggest it, most will switch gasoline brands and grades as an inexpensive diagnostic test. If, as is likely, the pinging goes away with the low-octane fuel, everybody wins.

 

The reason for the change of fuel brands is different fuel manufacturers blend their fuels differently. Sometimes, a blend of lesser octane may go to a dealer. The pump at the station may be labeled 87 octane, but in fact, the gas being pumped may be less than that. Subaru vehicles are designed to operate on 87 octane or better.

 

If your customer has put premium in the vehicle in an attempt to cure the ping, tell him or her to go back to a regular grade gasoline when switching brands. SVX and Legacy Turbo models must have premium gas to operate

properly.

 

It should also be pointed out that one tank of fuel may not make the problem go away since the new gas will mix with the old gas and will be ‘diluted.’ It may take several tanks of this other gasoline before the customer notices a change. So explain that this is not going to be an overnight cure. Also, suggest that the motorist stay away from non-major brands since the quality of the fuel may be questionable.

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Well, I read this thread few days ago and decided to relocate my knock sensor.

My KS has been replaced few monthes ago (the old one was cracked) bcoz he threw CEL while going uphill with the gas pedal on the floor.

 

Anyway, since relocating the KS (as shown in the first post) the car pulls amazingly and it _seems_ to be more economical in fuel consumption. I guess i will finish the "fuel consuption test" in about 1-2 weeks - but I would have like to know if there's anybody who tried this thing and had success with better fuel consumption and performace.

 

10x

 

Itzik

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I relocated my sensor on my 01 Forester.

I didn't notice much difference.

The light comes on less frequently but still comes on.

 

Performance is the same.

Fuel ecomomy is the same.

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If the KS is faulty/going faulty (i.e. giving knock sensor codes), relocating it won't help. Fuel economy/power may increase if ECU was pulling timing due to detecting knock and now after relocation it is not detecting knock. If KS is functioning properly and engine is not knocking and ECU is not pulling timing based on KS signal, then relocating it will make 0 difference.

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If the KS is faulty/going faulty (i.e. giving knock sensor codes), relocating it won't help. Fuel economy/power may increase if ECU was pulling timing due to detecting knock and now after relocation it is not detecting knock. If KS is functioning properly and engine is not knocking and ECU is not pulling timing based on KS signal, then relocating it will make 0 difference.

Exactly. Because of that i asked if someone has already expirienced this procedure and can tell us more.

 

Itzik

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Cool. I pulled mine completely, wrapped it in bubble wrap, and grounded the bolt hole. Didn't notice any difference, but I wasn't having issues before I did it either. Been that way for 6 months. Maybe I'll put it back in now.

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I re-gapped my plugs, well 3 of them, the last on requires more effort. I gapped em at like .42ish. It seemed to help, I also ran a bottle of techron. I'll prolly run another bottle after I fill up with some mobil gas. Every once and a while it will stumble, but I think it's getting better.

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Update: A friend of mine, from work, done the same relocating on his car, impreza 2003 AWD GX (2.0L), and he confirmed good results about performance (car "pulls" m-u-c-h better).

 

Itzik

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Well, i had some time to do a small fuel economy test after relocating the knock-sensor.

On mixed driving i've got 26MPG. I'd says its pretty damn good. Probably on highways it can get more. I'll do some tests in urban driving to see whats the diffrence before and after, especially on heavy traffic and stop&go traffic.

 

Itzik

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