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Discussion Starter · #1 ·
I was thinking about using the stock EGT sensor on the up-pipe for my egt gauge (when I get them). Any opinions as far as accuracy and piggy backing the sensor for two purposes. Thanks.
 

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Slvr,

I am gonna do the same thing,

Anxious to see the replies we get.

One person that has some ideas about it is Trey COBB;)

(Cobb doesnt mention using it for the gauge, But he does recomend leavin the O.E.M E.G.T in the pipe)

Shotgun
 

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The stock sensor is way to far away from the motor to be effective.
 

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The only reason I would like to keep the O.E.M E.G.T is that I believe since it tells the E.C.U that the U.P Cat is too hot it would be nice if COBB/Vish/TurboX,etc could set up your E.C.U to shut down the car (i.e Limp Mode) if your E.G.Ts got to high..

Ideas?

Shotgun

Edit: Of course since I will be runnin a gutted U.P their would have to be a way to compensate for the temps,......right?
 

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With a gutted uppipe or other catless uppipe, the stock EGT sensor will eventually throw a P0546 CEL. This is caused by the ECU seeing lower EGT temps than it expects, which is what you want with a catless uppipe. However, if you leave this CEL on long enough, the ECU will get progressively worse and throw other codes eventually leaving your car in limp mode or shutting down the engine all together. The fix is to just use a 2.2K Ohm 1/2W resistor in the female end of the EGT sensor connector. Then get a real EGT gauge installed and keep your eyes on that instead.

Calvin
 

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Ive had my gutted uppipe on my car for close to 3000 miles and have gotten no CEL yet.
 

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Discussion Starter · #8 ·
yeah, that's what I thought. I would naturally think it would be better to use the sensor that comes withe the sensor. I was just thinking about a little less labor for me as far as tapping and mounting the additional sensor. Thanks to everybody for their opinions. Keep them coming.
 

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There's probably going to be compatibility issues. The sender (probe) sends out a current range which the meter reads. Different senders give different ranges of current, so obviously, you need a meter that can read the range properly.

for example, I swithced from a 80 psi oil pressure gauge to a 150psi pressure gauge. The guy at the gauge shop, swithced out the senders also.

SO I doubt that teh oem egt sender will transmit the exact range of current that your after market gauge will read and interpret accurately. Especially if ones JDM and the other is not.

I don't know much about electrical stuff, just pointing out what seems to make sense to me.

Hg.
 

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pityr said:
Ive had my gutted uppipe on my car for close to 3000 miles and have gotten no CEL yet.
I put my uppipe in at 4k miles and only now has the P0546 CEL come up at 23k miles. You may not have it now, but it will come up eventually.

Calvin
 

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So if your aftermarket up-pipe comes with the bung, so you have to use the stock sensor, can the resistor still be used?
 

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Yes. I just disconnected the EGT sensor and put a resistor in the female end. I decided to leave the sensor in the bung since it's hard to reach. You can take it out and replace it with a bolt if you'd like.

Calvin
 

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I read somewhere that a catless uppipe wouldn't throw a cell light. Only the downpipe would throw a cell if you went catless, such as the HKS downpipe. (which I bought) They have MIL eliminators for the downpipe cell, but I haven't heard of one for the uppipe.
 

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Check out what cnk has to say. The people who say that an up-pipe won't throw a CEL probably just didn't wait long enough.

So Calvin, the resistor is on the actual sensor in the up-pipe, or on the wire that goes to the sensor (from some harness I assume)? Since I haven't installed my up-pipe yet, should I just throw a bolt in the hole?
 

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Well, couldn't you just resert the ecu every......10k miles, im sure its not a problem;)
 

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Bask Oner said:
Check out what cnk has to say. The people who say that an up-pipe won't throw a CEL probably just didn't wait long enough.

So Calvin, the resistor is on the actual sensor in the up-pipe, or on the wire that goes to the sensor (from some harness I assume)? Since I haven't installed my up-pipe yet, should I just throw a bolt in the hole?
The resistor goes in the female end of the connector. It's the 3rd one down under the plastic coverplate in front of the passenger front strut. If you're doing the uppipe install, you could just get a 12x1.25 bolt IIRC to plug the hole and just pop the resistor in the open connector. Make sure to use some electrical tape to cover and seal the resistor in to the connector to keep it from popping out and away from the elements.

Calvin
 

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WRXG0blin said:
Well, couldn't you just resert the ecu every......10k miles, im sure its not a problem;)
I tried doing that, but apparently once you get it, it comes back rather quickly. I have an OBD-II scanner and reset my ECU 3 times before giving up and just doing the resistor mod. Besides, everytime you reset your ECU, you have to put up with crappy performance until the ECU relearns.

Calvin
 
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