Misfire and a gas temperature sensor what do I do!?!?

ksm271 · 07-05-2008, 09:55 PM

ALRIGHT ..... SO I HAVE A 05 WRX. NOT A LOT OF MODS SINCE I BARELY STARTED, ALL I GOT ON IT AT THE MOMENT IS A CAT BACK, ACT CLUTCH AND FLYWHEEL, BOOST CONTROLLER BY GREDDY AND BOV.....

IVE HAD THE CAR FOR ABOUT ALMOST ABOUT TO BE A YEAR-(IN LIKE 4 MONTHS YAY!!!)
ANYWAY-I WAS DRIVING FROM WORK ONE DAY AND ALL OF A SUDDEN I GOT CHECK ENGINE LIGHT-IMMEDIATELY I LOST ALOT OF POWER. I RAN IT THROUGH THE COMPUTER AND GOT A P0303(CYLINDER #3 MISFIRE DETECTED)...
JUST TO BE SAFE I CHANGED ALL THE SPARK PLUGS/REPLACED THE COIL PACK ON THAT CYLINDER(IM PRETTY SURE ITS THE CYLINDER RIGHT INFRONT OF THE PASSENGER SIDE SEAT....RIGHT???.) ANYWAY- I TOOK IT OUT AND RAN IT. I GOT THE EVIL LIGHT AGAIN!!!- THIS IS WHAT IT READS THIS TIME-

P0546
Exhaust gas temperature sensor circuit high input

IM COMPLETE LOST NOW-I DONT KNOW WHAT THE HELL IS WRONG WITH MY SUBY.
IT FEELS LIKE IF ITS BEING RESTRICTED. THE CAR WILL NOT GO PAST 5 RPMS, NOT TO MENTION THAT IT STRUGGLES TO GET THERE.

SOMEONE PLEASE HELP ME!!! - IM THINKING IT MIGHT BE MY CATALYTIC BUT IM NOT SURE..... CAN ANYBODY TELL ME WHATS GOING ON??
-I'D REALLY APPRECIATE IT.

nagyhead · 07-06-2008, 11:00 AM

Damn stop yelling!

You can remove the EGT sensor from the up pipe and plug the hole with a M12x1.25 bolt. follow the wire up until you see a connection, remove the sensor and its wire. get a 2.2k ohm 1/2 watt resistor from Radio Shack and bend it in half and stick the 2 ends into the connection that the sensor plugged into. reset your ECU by pulling the battery cable and stepping on the brake until you odometer disappears.
Although this will not make the car rev past 5 grand. that is a completely separate issue

wagonracer · 07-06-2008, 11:53 AM

Yes, you are correct re the location of cylinder #3.

I would be suspicious of the boost controller and whether you're tuned for it. If you get greedy with the boost, esp with a MBC, you can send your car into a limp mode, since the stock EM has a limiter for the turbo. If I recall correctly it's based on turbo RPMs, not boost level. Anybody know for sure?

The resistor mod described above will prevent the CEL that you got, I've had it on my car for ages with no problems, but I think you are experiencing tune issues. Try pulling back the boost, reset the ECU as described above and see what she does then.

Now, another possibilty that could be causing the misfire CEL, would be your BOV. If it doesn't recirculate, you can create a very rich condition at partial throttle. Was the plug fouled badly ?

Once you get the car running better, do some diligent searching here in these forums, learn about BOV's, boost controllers and engine management. You'll be glad you did

ksm271 · 07-07-2008, 05:04 PM

yeah you know what there are not a lot of people that work on wrx's in my area. so im glad i decided to jump online and try to talk as much as i can well i did what you guys told me, the CEL went away, I also turned the boost low, and then I turned it completely off. so far the car sounds and runs smoothly at the first 3 to 4 rpms, its starts to struggle after 4 though, the CEL is gone, but I'm still lacking a lot of power. the plug is fine so far that I can tell- i also noticed another thing though, it seems that the blow off valve was not acting like a bov. in fact when I rev her up to high rpms, the bov starts sucking in air as well.
again, the car feels restricted-i havent had a problem with it recirculating either-
and thanks for the heads up-i will definitely be checking these forums out-

can it be the cat?, can it get clogged? downpipe?

03 CrazyTaxi · 07-07-2008, 08:30 PM

Quote:

Originally Posted by ksm271

can it be the cat?, can it get clogged? downpipe?

Well, if you had P0420 then yeah it would be the cat. Since you don't, it may be something else.

ksm271 · 07-08-2008, 06:01 PM

damn...well I really dont feel like taking it to the dealer but I dont think I have a choice-i also thought that it wouldn't be the cat. I have a apexi cat back system on it, but i haven't had a problem with it ever. Up pipe? Down pipe?, I dont know if im mistaken, but isnt the sensor that is giving me this light on the up pipe? Im so confused!..

03 CrazyTaxi · 07-08-2008, 06:28 PM

Sounds alot like you are in limp mode. Are you hitting full boost? If not, it's def. in limp mode. That means it's something you'll really want to get looked at quickly. You may have to suck it up and go to the dealer. Looks like you have an 05, is it still under warranty?

ksm271 · 07-09-2008, 08:09 PM

Yeah actually at the moment I think it is under warranty. That I know of its 30,000miles and/or 3 years, and yeah its a 05 so I think ill take it in, I'm one of the fortunate ones that has a dealership that will take cars even though they have been heavily modified, I barely have a few things on mine so its definitely not going to be a problem. Also, can anyone explain what would cause it to go to limp mode?. Also.. whats a limp mode on the car ?
I don't want to sound like a retard, but I'm barely getting into this whole tuning thing,

so I would appreciate it if anyone explained it to me.

thanks

ride5000 · 07-10-2008, 08:12 AM

could be a maf sensor issue. take it off and clean it.

pull all 4 plugs, check the condition, regap if necessary. i always like to test compression every time i pull the plugs.

check and replace your air filter if necessary.

sfelix818 · 07-10-2008, 11:12 AM

Did you reset the ecu, like nagyhead said ^^^??

ksm271 · 07-10-2008, 06:04 PM

Yeah I tried it, it kinda seem to work-the CEL went away, I could feel the car responding a little bit better this morning- unfortunately when I was coming home this afternoon it came on again- the car went into limp mode once more( i understand what that is now!

, anyway-I was reading one of the forums in here and I found that somebody had almost the same problem were the car felt like a N/A one, he said he replaced that downpipe or the up pipe (dont remember ) that had the one of cats on it. he said the car came back to life..
I hope thats it- I got a little bit bummed when another person had the same thing too and found out it was his turbo .

great reason to upgrade- but with this financial crunch right now- im not ready for that yet.

03 CrazyTaxi · 07-13-2008, 12:06 AM

Limp mode cuts boost and lowers the rev limiter. Basically it's so you can limp the car to a shop to have it looked at. You can also put the car into limp mode manually by plugging the 2 green connectors under the dash near the fuse panel together.