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Discussion Starter #1
Hey All,

First post here, but have been reading a little and can't seem to find the exact thread I'm looking for. I recently had a cat-back installed on my '08 WRX hatch and a couple days later noticed that the idle was sitting at or slightly below 500, sometimes dipping really low and almost dying on me. This was in San Francisco with hills that made me really start hating life. Luckily it didn't die, but I was pissin' my pants for about 15 minutes...

Anyways. The Catback is the only hp related mod on the car. No intake, DP, turbo or engine upgrades. Do you think it's possible that since the catback is allowing exhaust to flow at a higher rate (3" catback), it's not providing enough restriction and therefore the engine is being "starved" for air / fuel? In other words, the intake to exhaust ratio is off? I've read a few threads with people saying they took their throttle body out, cleaned everything real well and their idle was good to go. My car only has 63k on it, so I don't know if the throttle body would be too gunked up, but perhaps it's gunked up enough to where my newly installed exhaust is causing idle issues?

Does anyone know how I can re-map / reset my computer to idle properly? Is it a simple adjustment on the throttle cable? Do I need to plug it in to something? If first step is to just open up the intake and clean the throttle body, anyone know off the top of their head how long this might take?

Thanks in advance, and sorry for the semi-long post!
 

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2001 A.W. L
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^^meaning unplug the negative battery cable and let it sit for a few minutes

But before you do that, do you have a check engine light on?
 

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2001 A.W. L
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to answer your tuning questions, you are drive by wire, so you need a tuner to plug into your OBD port to tune the car. Or you can get a COBB AP, if you go the AP route you will need to do your upgrades to match their preconfigured "stages" unless you get a Protune
 

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Discussion Starter #5
No check engine light on. If I shouldn't unplug the battery since there isn't a check engine light, please let me know. I have a feeling I should be good to go since there's no light, but will double check on here prior to actually unplugging it. Otherwise, I'll give the reset a try by unplugging the negative cable and will cross my fingers for 5 minutes.

I thought about going for a COBB AP a little ways down the road after getting CAI and a downpipe, so thank you for the information / recommendation on that, too.

Thanks for the quick answers guys! I'll try that out tonight when I get home and will let you know if it worked / didn't.
 

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00'RS/02' WRX stgEleventy
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To do a proper ECU reset you need to pull the battery connection and tap the brake for 30sec..

Then when you start the car DO NOT touch the gas pedal..

Do not touch the gas pedal until after the car has warmed up completely to the point the cooling fans come on.. at that point you shut the car off..

ECU reset complete... (yes you dont touch the gas the entire time)

Sent from an other planet (Tapatalk)
 

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Just didnt want you to reset your ECU if you had a CEL on without checking it first :)
 

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Discussion Starter #8
Great, thanks all for the feedback. I will try the restart / brake pump / shut off tomorrow and will let you know if that ends up working out. If not, will be open to other suggestions and input then!
 

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00'RS/02' WRX stgEleventy
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Start with the basics..

And you need to start with a cold car.. disconnect the batt, drain the car (press brake), reconnect and start the car, after turning the key for about a 10 count before actually starting it..

I forgot that last part

Sent from an other planet (Tapatalk)
 

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Discussion Starter #10
Hey Aaron,

Thanks for the more thorough explanation. Quick question on the last part of your sentence though: "After turning the key for about a 10 count before actually starting it.."

Is that just leaving it in the "On" position with out actually turning to ignition, or is that turning to ignition and holding it for 10 seconds because that's how long it will take for the engine to turn over? I plan on doing this after work, and will let my car sit for an hour or two before doing this to allow it to cool down. My plan is as follows (please correct any steps if they're wrong!):

1) Get home, let car cool off for a couple hours.
2) Put car in neutral, disconnect the battery, and hold my foot on the brake completely draining any leftover electricity. Hold foot on brake until no brake lights turn on, then an extra 5-10 seconds for good measure.
3) Reconnect battery, turn key to "On" position for 10 seconds, then ignition and hold for 10 seconds (unless one of those two is not necessary, but I might do both for good measure) but will make sure to start car with it in neutral, and will not pump the gas during start up. After it starts, I'll let it run for awhile until the fans kick on, then will shut it off.
4) Allow it to sit for 20-30 minutes, and will then go turn it on like normal, take it around the block and see if the idle is still being a b****. Either way, will post my results here tomorrow.

Thanks again everyone!
 

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00'RS/02' WRX stgEleventy
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Yes.. a 10 count with the car ON before starting.. it gives the sensors a chance to talk to the ECU

Sent from an other planet (Tapatalk)
 
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