rough idle/stalling issues

TurtDomonick · 01-25-2013, 08:15 AM

I recently purchased my second wrx and when at a light if I go to put it in 1st gear the rpms drop significantly and almost stalls/usually does. If I put the car in neutral it runs fine. The previous owner told me that its the lightweight flywheel causing this but I find that hard to believe. I've cleaned my IACV that I've seen some people say to do and still no improvement. It has brand new sparks, fuel filter, oil, tranny fluid, and a street tune all that I did when I got the car. The tuner said its the worst idle he has seen....Somebody please help!!!!

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HinshawWRX · 01-25-2013, 08:27 AM

Is this on the 04 WRX listed? Automatic or manual? Mods?

TurtDomonick · 01-25-2013, 08:34 AM

2004 wrx, blouch 20g, amr top mount, aem intake, OEM bov, prosport up pipe and headers, spt exhaust, 650cc injectors, sti block w/2.0 heads, sti fuel pump, act clutch and light weight flywheel

J-hop · 01-25-2013, 08:34 AM

Quote:

Originally Posted by HinshawWRX

Is this on the 04 WRX listed? Automatic or manual? Mods?

Automatics don't have flywheels...

TurtDomonick · 01-25-2013, 10:08 PM

Its a manual

TurtDomonick · 01-25-2013, 10:09 PM

I didn't say it was automatic...

J-hop · 01-25-2013, 10:53 PM

Quote:

Originally Posted by TurtDomonick

I didn't say it was automatic...

Yes I know. I was commenting on hinshaw asking if it was auto or manual. In your initial post you stated it had a lightened flywheel. Automatics don't have flywheels therefore your vehicle had to be a manual and the question was already answered....

What kind of compression are you getting?

Mario_Enzo · 01-26-2013, 04:04 AM

End of clutch life i'm affraid

TurtDomonick · 01-26-2013, 07:38 PM

Compression is good....could compression be the issue?

TurtDomonick · 02-08-2013, 09:59 PM

Help!!!!!

AutoXSully · 02-09-2013, 08:27 AM

I am new to Subaru's so some of these things might not apply but...... My understanding of lightwieght flywheels is that you will have an issue at idle and not when you put it into gear because it doesn't have the extra wieght/momentum to make the revolutions unless you adjust your Idle Control Valve (agian I may be wrong here). I would go buy a Service Repair Manual since they have diagnostic steps/trees to help you figure out where the problem is. You'll probably need a multi-meter too to do the diagnostic steps in the manual. If the manual doesnt help then I would check timing to make sure the CPS is set properly and is secure and then multi-meter all the sensors in the intake track to make sure they are working properly.

TurtDomonick · 02-09-2013, 04:47 PM

What do u mean by cps is set correctly wat is cps sorry?

tommyson01 · 02-09-2013, 04:49 PM

This may be a dumb question, but how does the air filter look?

AutoXSully · 02-09-2013, 04:59 PM

Camshaft Position Sensor (CPS).... you can rotate the sensor to adjust timing (in other cars that I have worked on). So if it isn't set correctly your timing will be off....which could give you a rough idle.

TurtDomonick · 02-10-2013, 12:53 AM

K thanks alot

logan redden · 02-10-2013, 03:13 AM

Is your foot still on the clutch when it starts idling rough??? If so.. your clutch is probably out of adjustment.. how new is the clutch?

TurtDomonick · 02-10-2013, 04:09 AM

If I'm at a red light and light turns green, I'll put it in 1st and start to roll forward then let's say the car in front of me has to stop for a quick second I'll then press the clutch in and that's when the rpms drop like crazy and get a ****ty idle. I hold the clutch in cuz its only a few seconds before I can roll again u know.

logan redden · 02-10-2013, 04:34 AM

My car is acting kinda the same.. what bov are you using? Stock Turbo? Bigger intake?

TurtDomonick · 02-11-2013, 01:08 AM

Stock bov 20g blouche n AEM intake

logan redden · 02-11-2013, 06:01 AM

Hmm.. I think I just fixed mine.. there is a large vacuum line that goes into my intake pipe.. i guess it slipped off.. also... it leads the into a "junction" that I believe 3 vacuum line attached to it.. also check those.. kind of a dinky setup.. on mine there is barly enough line to reach it so I'm afraid it might come apart...

Mr Wrex · 02-11-2013, 09:13 AM

Quote:

Originally Posted by TurtDomonick

If I'm at a red light and light turns green, I'll put it in 1st and start to roll forward then let's say the car in front of me has to stop for a quick second I'll then press the clutch in and that's when the rpms drop like crazy and get a ****ty idle. I hold the clutch in cuz its only a few seconds before I can roll again u know.

Think about it... you let your foot off the gas and the engine goes back to idle. The lighter the flywheel, the less rotational mass it has and the less energy it has to keep spinning longer while slowing down to idle (hooray inertia!). Because it slows down faster than a heavier flywheel would, it might cause the RPMs to drop too low and get close to stalling.

Does it also act like this when just revving in neutral? Aka, can you rev the car to about 2k RPM and replicate the stalling feel again? Can you ask the previous owner about what Brand/weight lightened flywheel he installed?

TurtDomonick · 02-12-2013, 11:36 PM

If I have it in neutral and just rev it to 2k and then let off no it will not drop and almost stall only when in gear. I totally agree with wat your saying and makes complete sense but how come some people don't have this issue IDK but I'll ask that guy and let u know. He did say it started every since the light weight flywheel install but the dudes a idiot and really can't trust **** he says I feel so just being cautious. I'll prolly pull it and see wat happens when a stock one is installed.

logan redden · 02-13-2013, 04:20 AM

So its only tryin to stall out under decel in gear with clutch depressed?? Or at all times when in gear with clutch depressed? Is it TBW?

TurtDomonick · 02-13-2013, 08:37 PM

Correct on decel with clutch pressed and in gear

nmlittlebigman · 02-13-2013, 09:28 PM

So what happens if you turn on your air conditioning? If IACV is good it should raise the rpms (at least that is what I have read on how to test it).

01-25-2013, 08:15 AM	#1
TurtDomonick Scooby Newbie Member#: 256779 Join Date: Sep 2010 Location: St.Pete FL Vehicle: 2004 Impreza WRX Silver	rough idle/stalling issues I recently purchased my second wrx and when at a light if I go to put it in 1st gear the rpms drop significantly and almost stalls/usually does. If I put the car in neutral it runs fine. The previous owner told me that its the lightweight flywheel causing this but I find that hard to believe. I've cleaned my IACV that I've seen some people say to do and still no improvement. It has brand new sparks, fuel filter, oil, tranny fluid, and a street tune all that I did when I got the car. The tuner said its the worst idle he has seen....Somebody please help!!!! * Registered users of the site do not see these ads.

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01-25-2013, 08:27 AM	#2
HinshawWRX n00b Moderator Moderator Member#: 140114 Join Date: Feb 2007 Chapter/Region: MAIC Location: Jolly ol York of VA Vehicle: 06 18G Semi Built SGM WRX	Is this on the 04 WRX listed? Automatic or manual? Mods?

01-25-2013, 08:34 AM	#3
TurtDomonick Scooby Newbie Member#: 256779 Join Date: Sep 2010 Location: St.Pete FL Vehicle: 2004 Impreza WRX Silver	2004 wrx, blouch 20g, amr top mount, aem intake, OEM bov, prosport up pipe and headers, spt exhaust, 650cc injectors, sti block w/2.0 heads, sti fuel pump, act clutch and light weight flywheel

01-25-2013, 10:08 PM	#5
TurtDomonick Scooby Newbie Member#: 256779 Join Date: Sep 2010 Location: St.Pete FL Vehicle: 2004 Impreza WRX Silver	Its a manual

01-25-2013, 10:09 PM	#6
TurtDomonick Scooby Newbie Member#: 256779 Join Date: Sep 2010 Location: St.Pete FL Vehicle: 2004 Impreza WRX Silver	I didn't say it was automatic...

01-26-2013, 04:04 AM	#8
Mario_Enzo Scooby Newbie Member#: 344928 Join Date: Jan 2013	End of clutch life i'm affraid

01-26-2013, 07:38 PM	#9
TurtDomonick Scooby Newbie Member#: 256779 Join Date: Sep 2010 Location: St.Pete FL Vehicle: 2004 Impreza WRX Silver	Compression is good....could compression be the issue?

02-08-2013, 09:59 PM	#10
TurtDomonick Scooby Newbie Member#: 256779 Join Date: Sep 2010 Location: St.Pete FL Vehicle: 2004 Impreza WRX Silver	Help!!!!!

02-09-2013, 08:27 AM	#11
AutoXSully Scooby Newbie Member#: 342320 Join Date: Jan 2013 Chapter/Region: MAIC Location: Norfolk- currently deployed Vehicle: 2013 STI Black	I am new to Subaru's so some of these things might not apply but...... My understanding of lightwieght flywheels is that you will have an issue at idle and not when you put it into gear because it doesn't have the extra wieght/momentum to make the revolutions unless you adjust your Idle Control Valve (agian I may be wrong here). I would go buy a Service Repair Manual since they have diagnostic steps/trees to help you figure out where the problem is. You'll probably need a multi-meter too to do the diagnostic steps in the manual. If the manual doesnt help then I would check timing to make sure the CPS is set properly and is secure and then multi-meter all the sensors in the intake track to make sure they are working properly.

02-09-2013, 04:47 PM	#12
TurtDomonick Scooby Newbie Member#: 256779 Join Date: Sep 2010 Location: St.Pete FL Vehicle: 2004 Impreza WRX Silver	What do u mean by cps is set correctly wat is cps sorry?

02-09-2013, 04:49 PM	#13
tommyson01 Scooby Specialist Member#: 154579 Join Date: Jul 2007 Chapter/Region: NWIC Location: Cochabamba Vehicle: 2002 WRX Wagon PSM - Sold	This may be a dumb question, but how does the air filter look?

02-09-2013, 04:59 PM	#14
AutoXSully Scooby Newbie Member#: 342320 Join Date: Jan 2013 Chapter/Region: MAIC Location: Norfolk- currently deployed Vehicle: 2013 STI Black	Camshaft Position Sensor (CPS).... you can rotate the sensor to adjust timing (in other cars that I have worked on). So if it isn't set correctly your timing will be off....which could give you a rough idle.

02-10-2013, 12:53 AM	#15
TurtDomonick Scooby Newbie Member#: 256779 Join Date: Sep 2010 Location: St.Pete FL Vehicle: 2004 Impreza WRX Silver	K thanks alot

02-10-2013, 03:13 AM	#16
logan redden Scooby Newbie Member#: 346516 Join Date: Feb 2013 Chapter/Region: NWIC Vehicle: 2005 WRX STI Blue	Is your foot still on the clutch when it starts idling rough??? If so.. your clutch is probably out of adjustment.. how new is the clutch?

02-10-2013, 04:09 AM	#17
TurtDomonick Scooby Newbie Member#: 256779 Join Date: Sep 2010 Location: St.Pete FL Vehicle: 2004 Impreza WRX Silver	If I'm at a red light and light turns green, I'll put it in 1st and start to roll forward then let's say the car in front of me has to stop for a quick second I'll then press the clutch in and that's when the rpms drop like crazy and get a ****ty idle. I hold the clutch in cuz its only a few seconds before I can roll again u know.

02-10-2013, 04:34 AM	#18
logan redden Scooby Newbie Member#: 346516 Join Date: Feb 2013 Chapter/Region: NWIC Vehicle: 2005 WRX STI Blue	My car is acting kinda the same.. what bov are you using? Stock Turbo? Bigger intake?

02-11-2013, 01:08 AM	#19
TurtDomonick Scooby Newbie Member#: 256779 Join Date: Sep 2010 Location: St.Pete FL Vehicle: 2004 Impreza WRX Silver	Stock bov 20g blouche n AEM intake

02-11-2013, 06:01 AM	#20
logan redden Scooby Newbie Member#: 346516 Join Date: Feb 2013 Chapter/Region: NWIC Vehicle: 2005 WRX STI Blue	Hmm.. I think I just fixed mine.. there is a large vacuum line that goes into my intake pipe.. i guess it slipped off.. also... it leads the into a "junction" that I believe 3 vacuum line attached to it.. also check those.. kind of a dinky setup.. on mine there is barly enough line to reach it so I'm afraid it might come apart...

02-12-2013, 11:36 PM	#22
TurtDomonick Scooby Newbie Member#: 256779 Join Date: Sep 2010 Location: St.Pete FL Vehicle: 2004 Impreza WRX Silver	If I have it in neutral and just rev it to 2k and then let off no it will not drop and almost stall only when in gear. I totally agree with wat your saying and makes complete sense but how come some people don't have this issue IDK but I'll ask that guy and let u know. He did say it started every since the light weight flywheel install but the dudes a idiot and really can't trust **** he says I feel so just being cautious. I'll prolly pull it and see wat happens when a stock one is installed.

02-13-2013, 04:20 AM	#23
logan redden Scooby Newbie Member#: 346516 Join Date: Feb 2013 Chapter/Region: NWIC Vehicle: 2005 WRX STI Blue	So its only tryin to stall out under decel in gear with clutch depressed?? Or at all times when in gear with clutch depressed? Is it TBW?

02-13-2013, 08:37 PM	#24
TurtDomonick Scooby Newbie Member#: 256779 Join Date: Sep 2010 Location: St.Pete FL Vehicle: 2004 Impreza WRX Silver	Correct on decel with clutch pressed and in gear

02-13-2013, 09:28 PM	#25
nmlittlebigman Scooby Specialist Member#: 321409 Join Date: May 2012 Chapter/Region: SWIC Location: Arrey, NM Vehicle: 2011 WRX STi Sedan WRB Stage II T.P. tuned	So what happens if you turn on your air conditioning? If IACV is good it should raise the rpms (at least that is what I have read on how to test it).