Gas Pedal Problem - ClubWRX Forum - Subaru Impreza WRX and STi Community and Forums

Ant428 · 09-11-2009, 07:54 PM

Hi there. I have just installed new headlights in my 08 Subaru wrx. In order to do so, I had to remove the battery and the K&n Intake. After I was finished, and hooked everything back up, I notice a significant change in throttle response. If i just touch the gas, it doesn't do anything. Before, when I touched the gas pedal slightly, the engine would rev. What happened?

p.s Are 80 watt bulbs safe...?

Regards,
Anthony

wrxnews · 09-11-2009, 08:13 PM

If i'm not mistaken your ECU has to "relearn" how you drive.

Do a search because it's been covered here on the forum before...it should turn up.

Off the top of my head you can speed that process up if thats the case by gently braking while in 3rd gear...but alas it escapes me.

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**mycologist** · 09-11-2009, 08:51 PM

I would look at the way the intake is put back together and check/clean the MAF connection.

The ECU shouldn't reset unless you drain the residual power and relearning isn't that severe.

EvoEatr · 09-12-2009, 03:58 PM

As mentioned the ECU has to relearn the way your drive. The biggest problem with this is throttle position because all the newer Subarus are throttle by-wire. Sometimes on higher mileage Subarus with throttle by wire you have to pull out the air intake and clean the carbon out of the throttle body fore the ECU is initially getting the wrong reading if there is any carbon in there ( sticking the throttle plate open a tad)...Give it a few days It should be back to normal..or If you have the time I would pull off the intake and clean the throttle plate/body and after doing that let the car idle for a few min...

'02 wrx · 10-25-2009, 03:37 PM

Quote:

Originally Posted by EvoEatr

As mentioned the ECU has to relearn the way your drive. The biggest problem with this is throttle position because all the newer Subarus are throttle by-wire. Sometimes on higher mileage Subarus with throttle by wire you have to pull out the air intake and clean the carbon out of the throttle body fore the ECU is initially getting the wrong reading if there is any carbon in there ( sticking the throttle plate open a tad)...Give it a few days It should be back to normal..or If you have the time I would pull off the intake and clean the throttle plate/body and after doing that let the car idle for a few min...

Just curious, how new are you talking when you say "newer subarus"? i have a 2002 wrx and i think its starting to do what Ant428 wrx is doing but everything is stock. to be more specific, at random times when i shift, let the clutch out, and hit the gas, there is no throttle response for X amount of seconds and then the the throttle comes back and the car jumps forward and normal driving resumes. i'm a noobie and this is freakin me out. thanks in advance

EvoEatr · 10-25-2009, 04:28 PM

Quote:

Originally Posted by '02 wrx

Just curious, how new are you talking when you say "newer subarus"? i have a 2002 wrx and i think its starting to do what Ant428 wrx is doing but everything is stock. to be more specific, at random times when i shift, let the clutch out, and hit the gas, there is no throttle response for X amount of seconds and then the the throttle comes back and the car jumps forward and normal driving resumes. i'm a noobie and this is freakin me out. thanks in advance

Your 02 WRX has a throttle cable...I would make sure the throttle isn't sticking and I would also make sure the throttle body isn't carboned up fore I've seen a carboned up TB cause problems like your describing...Also make sure the cable is free and isn't getting hung up on anything...

'02 wrx · 10-25-2009, 05:12 PM

Quote:

Originally Posted by EvoEatr

Your 02 WRX has a throttle cable...I would make sure the throttle isn't sticking and I would also make sure the throttle body isn't carboned up fore I've seen a carboned up TB cause problems like your describing...Also make sure the cable is free and isn't getting hung up on anything...

thanks a bunch. sorry but i have one more question regarding the throttle body. this cleaning process i imagine would most likely mean taking the tb off. is that something i can do at home or is it best to take it to a dealer/shop? thanks again

EvoEatr · 10-26-2009, 02:31 AM

no prob. man.. this is a shot from the hip from the info. youve given me..lol...no you can leave the throttle body on..however you will have to remove the intercooler which is pretty easy..two hose clamps a couple vacuum lines and 2 bolts...you should be able to move the throttle by hand and kind of feel whether its sticking or not...anyways maybe here will be of some assistance.. Impreza Manuals | ken-gilbert.com

**Donkey** · 10-26-2009, 08:22 AM

Quote:

Originally Posted by Ant428

p.s Are 80 watt bulbs safe...?

Regards,
Anthony

80 watt bulbs are illegal and very unsafe for the other drivers on the road and your light housings due to the amount of heat they would put off.

'02 wrx · 10-26-2009, 04:14 PM

thanks again EvoEatr

jeremy96gase · 10-26-2009, 04:39 PM

Quote:

Originally Posted by Donkey

80 watt bulbs are illegal and very unsafe for the other drivers on the road and your light housings due to the amount of heat they would put off.

+1

This thread is for a bugeye, but the materials used for the headlight and harness are the same as your car.
Headlights burning out - WRXFanatics.com WRX Forums

55/65 watt bulbs are what you should be using.

EvoEatr · 10-26-2009, 05:53 PM

Quote:

Originally Posted by '02 wrx

thanks again EvoEatr

no prob man..let me know how it turns out...

09-11-2009, 07:54 PM	#1
Ant428 Registered User Join Date: Oct 2008 Posts: 4	Gas Pedal Problem Hi there. I have just installed new headlights in my 08 Subaru wrx. In order to do so, I had to remove the battery and the K&n Intake. After I was finished, and hooked everything back up, I notice a significant change in throttle response. If i just touch the gas, it doesn't do anything. Before, when I touched the gas pedal slightly, the engine would rev. What happened? p.s Are 80 watt bulbs safe...? Regards, Anthony

09-11-2009, 08:13 PM	#2
wrxnews Registered User Join Date: Mar 2009 Location: North Crackalacka Posts: 191	If i'm not mistaken your ECU has to "relearn" how you drive. Do a search because it's been covered here on the forum before...it should turn up. Off the top of my head you can speed that process up if thats the case by gently braking while in 3rd gear...but alas it escapes me. Unabombers Manifesto Unabomber's Manifesto - NASIOC __________________ <-----#1 Fanboi Stink-Eye-Mob #19 ECU cracked by RomRaider

09-11-2009, 08:51 PM	#3
mycologist The Mushroom Moderator Join Date: Oct 2005 Location: Late Devonian Posts: 6,536	I would look at the way the intake is put back together and check/clean the MAF connection. The ECU shouldn't reset unless you drain the residual power and relearning isn't that severe. __________________ "From a little spark may burst a mighty flame." - Dante "The stitch is lost unless the thread is knotted." - Italian proverb

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09-12-2009, 03:58 PM	#4
EvoEatr Registered User Join Date: Aug 2008 Location: Kennett Square, Pennsylvania Posts: 1,572	As mentioned the ECU has to relearn the way your drive. The biggest problem with this is throttle position because all the newer Subarus are throttle by-wire. Sometimes on higher mileage Subarus with throttle by wire you have to pull out the air intake and clean the carbon out of the throttle body fore the ECU is initially getting the wrong reading if there is any carbon in there ( sticking the throttle plate open a tad)...Give it a few days It should be back to normal..or If you have the time I would pull off the intake and clean the throttle plate/body and after doing that let the car idle for a few min...

10-26-2009, 02:31 AM	#8
EvoEatr Registered User Join Date: Aug 2008 Location: Kennett Square, Pennsylvania Posts: 1,572	no prob. man.. this is a shot from the hip from the info. youve given me..lol...no you can leave the throttle body on..however you will have to remove the intercooler which is pretty easy..two hose clamps a couple vacuum lines and 2 bolts...you should be able to move the throttle by hand and kind of feel whether its sticking or not...anyways maybe here will be of some assistance.. Impreza Manuals \| ken-gilbert.com

10-26-2009, 04:14 PM	#10
'02 wrx Registered User Join Date: Mar 2009 Location: NH Posts: 20	thanks again EvoEatr