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HELP reoccuring EGT sensor breaking

7.1K views 19 replies 7 participants last post by  Nate Hurd  
#1 ·
So i posted a thread before because i kept getting a p0546 to pop up with a stock wrx (minus the BOV). well subaru has replaced this egt sensor twice and is now saying that the sensor is getting damaged, they dont know how but they say it seems to be the turbo and are pulling it tomorrow. car has a salvaged title so it could be anything but im hoping somebody can tell me what i may be looking at here? are turbos repairable, would they have the capability of breaking the egt sensor over and over or is it something else. if i need a new turbo should i upgrade or just get another 03 oem
 
#3 ·
Personally I wouldnt do to much upgrading when it comes to the turbo on the stock EJ20. However, I know the VF39 and VF43 are popular upgrades from the stock TD04... How many miles are on this vehicle?...Your saying that the EGT sensor is getting physically damaged (likes pieces breaking off) in the exhaust pipe?
 
#4 ·
I wouldn't be surprised if the Previous Owner decatted the UP. Be prepared for the dealership to demand $1000 from you to put a brand new UP in the car.

When you gut the UP and leave the EGT sensor in, it apparently likes to break off and get sucked into the turbo. That usually destroys the turbo, though.
 
#5 · (Edited)
I wouldn't be surprised if the Previous Owner decatted the UP. Be prepared for the dealership to demand $1000 from you to put a brand new UP in the car.

When you gut the UP and leave the EGT sensor in, it apparently likes to break off and get sucked into the turbo. That usually destroys the turbo, though.
I have never heard of/seen this..I have def. heard of the cat breaking apart and getting sucked up in there...lord, you would think the EGT sensor is solid enough that the spool from the turbo wouldnt produce so much suction to snap the sensing tip off...
 
#6 ·
I agree with the posts above. Many replace the Upipe with an after market pipe that has no cat in it. This allows for better airflow, spool, etc. The EGT sensor is a little needle sensor that has the capabilty of breaking off and either getting sucked into the turbo or forced into the motor (depending if you're in vaccum or boost at the time of breaking). Now, what most people do to take care of this issue is remove the sensor completely and basically soder a resistor in the wiring to defeat it totally. Then, they plug the hole in the Upipe, and go on their way. You might find this is the route they took, and the resistor has actally failed / been removed. They might not even find the sensor! Or, a lot of people (after they've defeated the sensor with the resistor) just cut the sensor needle off and screw it back into the hole in the new Upipe, because they have no bolt to go in the bung.

To agree with the above, if they find any of what I described above, they will request to replace the Upipe and egt sensor, and that + labor will net you a $1000 bill. My recommendation is if they do say that, decline. Bring it home and do the EGT sensor delete that I've decribed. You'll run just fine and won't have any more codes. Search the forum for exact instructions on how to do it! :wiggles:
 
#8 ·
hey sorry i havnt gotten back sooner on this post(dealing with subaru a lot) so what they are telling me is that the catalytic converter is somehow loose, and under pressure is pushing the sensor up into the turbo futher than it should and the sensor tip is breaking off. now what is pissing me off is that they said they have found damage in my turbo because of these sensor breaking but say that its my fault that damage to the turbo happened. if the catalytic converter is doing its job just fine but is loose i will do the resister mod being i plan on putting up pipe and downpipe mods on there eventually anyway. the car only has 18000 miles as it is a salvage title and sat in a guys driveway for 3 years.(he told me nothing was wrong with car then found out 100 miles later he put non turbo'd center and rear diffs on the thing after the accident). anyway ive been reading whats going on with turbo upgrades with the td05, do i have to do the same upgrades with those turbos youve recommended? and does anyone have any advise to what im legally entitled to with subaru being they misdiagnosed my problem twice resulting in my turbo being damaged from these sensors breaking off because i just talked to them and they say they will not pay for a thing.
 
#9 · (Edited)
the catalytic converter is somehow loose, and under pressure is pushing the sensor up into the turbo futher than it should and the sensor tip is breaking off.
I've read warnings about how this could happen. I think this is the first documented case I've read on the subject.

It might be time to cut your losses.
Just buy an aftermarket uppipe, used TD04, and either install them or have a local tuner install them.
The sensor that keeps breaking off will be removed, and a resistor needs to be inserted in to the sensors plug.

The Dealer won't install aftermarket uppipes due to emissions standards.

Edit : Knowing that the Pre-cat is loose requires that section of pipe be replaced. It's only going to get worse, and with time the cat material will continue break off and go in to the turbo.

The turbo was damaged the first time it ingested the EGT sensor. At that point you needed a new turbo, having it happen again after the dealer did some work doesn't really matter.

TD04's cannot be repaired. Installing something larger will require other mods (injectors, fuel pump, downpipe, tuning).

Having non-turbo diffs might be a problem if you start pushing too much power to the wheels.
 
#11 ·
As for turbo upgrades, the choices are vast, but just about anything other then the stock turbo (TD series) will require the following on your year:
-Injectors
-bigger IC (either TMIC or FMIC)
-Fuel Pump (Warblo 255 or equivilant)
-UP & DP
-Tune
 
#13 · (Edited)
ok so heres my issue, i live in california, and so not having a cat is a big no no, that being so they want to replace my cat for a new 600+$ one plus labor... Now the only code i am always getting is the p0546 because the sensor keeps breaking. my question is being that is the only code popping, is my cat working ok otherwise. is there a cel code for a cat not working properly because Subaru is saying since its loose its not working properly but i feel that i would be getting another code. If there is another code that would be popping up its quite obvious that subaru just wants more money and they can go screw themselves. I need to get the car smogged being i just bought it but i defintely wont have them smog it because theyll fail it on purpose to get more work out of me. Any ideas?

as to the damage of the turbo, they say that there is play in the bearing, and the fan(turbine?) is rubbing up on the walls not tremediously but there is evidence of damage. so thats why im wondering about the upgrading being id rather kill 2 birds with one stone (fixing turbo +upgrading it as well)
 
#14 ·
ok so heres my issue, i live in california, and so not having a cat is a big no no
There are lots of catless uppipe WRX's running around in California. The Uppipe is difficult to see, and only the people with a very keen eye will notice it. Just put the resistor in the EGT plug, and make sure there are no CEL's.

Now the only code i am always getting is the p0546 because the sensor keeps breaking. my question is being that is the only code popping, is my cat working ok otherwise.
If your cat is moving around then then it's not doing its job properly, and it needs to be replaced.

is there a cel code for a cat not working properly because Subaru is saying since its loose its not working properly but i feel that i would be getting another code. If there is another code that would be popping up its quite obvious that subaru just wants more money and they can go screw themselves.
There is not a cel for the uppipe cat not working improperly. The sensor that would figure this out is the O2 sensor. The front O2 sensor is before the uppipe cat, and the back O2 sensor is front of the rear cat.
As detailed here
Image

As you stated before they will want more money to fix this.

I need to get the car smogged being i just bought it but i defintely wont have them smog it because theyll fail it on purpose to get more work out of me. Any ideas?
Smog it without the uppipe cat, as long as you have the rear two and no CEL's the car will pass.

as to the damage of the turbo, they say that there is play in the bearing, and the fan(turbine?) is rubbing up on the walls not tremediously but there is evidence of damage. so thats why im wondering about the upgrading being id rather kill 2 birds with one stone (fixing turbo +upgrading it as well)
If the compressor fan is impacting the side walls then you need to replace the turbo.
As stated before if you want to upgrade the turbo at that time you can, but you must follow the mod path Truckster27 pointed out. Take note a catless uppipe and an aftermarket downpipe are required. The aftermarket downpipes can be a catted or catless.

Here is are the FAQ's you need to read.
Uppipe FAQ: Read if you are thinking of buying one! - NASIOC
Exhaust FAQ: Read if you are thinking of buying one! - NASIOC
Turbo FAQ: Read if you are thinking of upgrading! - NASIOC

Here are a bunch of other FAQ's you should read. Grab some popcorn.
http://www.clubwrx.net/forums/engine-modifications/80872-engine-performance-faq-read-me.html
Unabomber's Manifesto - NASIOC
 
#17 ·
Just FYI, the cat in the UP is a Pre Cat. It isn't used for regular emissions, it's only purpose is to reduce emissions when the car and engine are cold, and only for a short period of time. Removing the cat and putting a resister in place of the sensor worked very well for me, no DTC's or any other problems. In fact, I couldn't get the freaking EGT probe to seat properly after I removed it, so it was 'delete' or new probe, and I'm not dropping money on a new probe if it's just gonna break.

jeremy96gase, that's a nifty and useful diagram you posted, I'm going to use that to help me figure out what I want to do with my exhaust. :) Thinking downpipe, move the rear cat forward, put a series 40 muffler in there, and run a straight pipe out the back. Not sure if I want to keep the resonator or not.
 
#20 · (Edited)
Hay what's up guys.. So I have been trying to do this resistor mod for a couple of days and just can't get it to work.. I have a 03 impreza

The issue: I have replaced the EGT 3 times now then found this thread and decided to give it a try (cheeper that spending $350 that breaks with in 3 miles). so I am getting the P0546 and P0546 Pd code.

What I have done: I bought a package of the 2.2 ohm (1/2 watt) resistors and have located the Egt sensor connector on the passenger side just under the piece of black plastic held on by two quarter turn thumb screws and pulled the third connector down and attempted the resistor mod twice now. Both times drove it, each time I drive it the CEL comes back on with the P0546 and P0546 Pd codes. am I doing something wrong? I haven't soldered it or any thing. the first time I tried it I trimmed a little off the resistor legs and stuck them straight down the connector, then did it again not cutting the resistor but just bending (doubling over) the legs of the resistor, and still the CEL comes back on.. Any help would be greatly appreciated!!