car bogs at 2500 rpm

KINGSKY · 05-06-2003, 12:29 PM

i was wondering if any of u has a clue of what's going on. i have a GC8 w/ a WRX motor and tranny. when it hits 2500 rpm the car bogs. it feels like it will stall. it's like driving a stick for the 1st time.
after it passes 2700 rpm it's back to normal. any suggestions?
thankx.......

KINGSKY

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RimRockaz · 05-06-2003, 07:22 PM

what are your mods?

I had that experience when I first put in the BOV and LINK ECU. After getting rid of the BOV and tune the ECU, the car runs fine..

KINGSKY · 05-07-2003, 12:53 PM

all i have is a jun flywheel, upgraded clutch, samco IC hoses, jic xhaust. i think the problem is in ECU. i also have a CEL, with the error code of MISFIRE on all cylinders. thankx 4 the info.......

KINGSKY

Shag-e · 05-07-2003, 01:12 PM

Sounds like bad gas..... Is this common or something new?

KINGSKY · 05-07-2003, 01:57 PM

it's not the gas. my car recently had the swap done and it hesitated right off the bat.

KINGSKY

Shag-e · 05-07-2003, 02:03 PM

Well, I had a similar problem when I had my WRX, but it was bad till i hit 5K rpm. It was deduced down to bad grounding on the engine. Added bigger wiring and the problem went away.

Its worth a shot and it doesn't cost that much to fix.

Search under grounding mod to find out what I am talking about.
Hopefully that helps

RimRockaz · 05-07-2003, 07:00 PM

Quote:

Originally posted by KINGSKY
all i have is a jun flywheel, upgraded clutch, samco IC hoses, jic xhaust. i think the problem is in ECU. i also have a CEL, with the error code of MISFIRE on all cylinders. thankx 4 the info.......

KINGSKY

ok..since you have CEL w/ the error code of Misfire on all cylinders, maybe you should check or change the sparkplugs. A colder heat range of sparkplugs will probably help if the stock ones have gone bad.

Take care!

Coati · 05-08-2003, 01:22 PM

It's quite possible that the CEL is due to the JUN being very light (is is the lightweight or the ultralight?). This confuses the ECU, but there is no real misfire. This happened when I had a JUN in my WRX. For all I know, you have my old flywheel.

luvmyrs · 05-13-2003, 07:19 PM

one of the Tri-State members over here just did the same swap, he had some of the same symptoms as you. What it eventually came down to was a bad ECU. Try to see if someone local is willing to let you test with theyre ECU. If you wanna see the whole saga do a search on the username "Nizz". Goodluck with your project.
Frank

Puckaveli · 05-14-2003, 09:36 AM

What is your boost gauge showing at the time of the bog? Some VW's will actually boost faster than the ECU can keep up. The boost will surge then the ECU turns it back for a second. I doubt that's it but who knows.

stimpy · 05-14-2003, 05:07 PM

Sounds kind of like the wiring may be suspect. I'd try to confirm the wiring first. If that looks ok, then see if you can borrow an ECU from somebody else and see if that is bad. I've also heard of a misfire being thrown due to a lightweight flywheel, but I haven't heard about it having adverse affects.

Did you do the swap or did you pay somebody to do it?

-Jon

KINGSKY · 05-17-2003, 10:00 PM

problem solved. changed the rear diff and changed out the whole tranny. no more CEL, no more hesitation. hey andrew, thankx dude...

KINGSKY

STi-Nismo Dood · 05-18-2003, 05:16 AM

how did the tranny make you pull CELs?

KINGSKY · 05-18-2003, 08:23 PM

i had a JUN ultralight flywheel, i guess that's the cause.

stimpy · 05-19-2003, 01:07 PM

So are you still running the ultralight flywheel? It sounds odd that if you replaced the tranny/rear diff and kept the FW then your CEL was being caused by something other than the FW.

-Jon

KINGSKY · 05-19-2003, 04:20 PM

stock clutch/flywheel are being used.... no more JUN.

stimpy · 05-19-2003, 04:46 PM

Ah, ok. That makes sense then. Was this the 9lb flywheel or the 12lb flywheel? This is actually one of the mods I was seriously considering for my swap (the 12lb flywheel that is).

In a different post in the FFI forum, a vendor mentioned that they had to actually raise the idle rpm by a few hundred to resolve the issue. What was happening was the decel was happening too fast for the IAC valve to catch it properly. Stumbling was supposed to be one of the byproducts of this.

-Jon

Cacophony · 05-19-2003, 07:07 PM

Is this for real?

I had an 11lb unorthodox racing flywheel in my 2.5RS and never had a problem.

Now that it's an STi V, there's a JUN ultralight in there. I don't have a stock ecu

but I don't have any idle problems either...

stimpy · 05-19-2003, 07:11 PM

I hadn't heard of it on anything before recently. I know of a WRX and an RS using the 12lb JUN flywheels without a problem. If you remember the fellow on here by the name of efoo, well his Tec 2 couldn't handle his lightweight flywheel and the car would die due to the IAC not catching it quick enough. That is the only other time I can remember a problem.

I have heard of lightweight underdrive pulleys throwing misfire codes due to the lack of the balancer though. Could it be that the flywheel was causing misfire codes due to an imperfection in it? Just throwing out ideas here...

-Jon

STi-Nismo Dood · 05-20-2003, 04:15 AM

my friend once told me that Sports Compact Car did an article on a stock pulley v. the Unorthodox pulley and found that the harmonic balancer did as well as the stock's through their tests... dunno what kind of car though.

stimpy · 05-20-2003, 06:43 PM

I've heard conflicting opinions on that. There are many proponants of the stock harmonic dampener on inline fours. However, the flat four is very well balanced. Last time I checked, Trey Cobb and Christian ( Modern Garage) both were against the underdrive pulleys. Shiv used to be against them but after about 2 years, he started selling his own version.

-Jon

05-06-2003, 12:29 PM	#1
KINGSKY Scooby Specialist Member#: 31154 Join Date: Dec 2002 Location: SUNNYDIEGO 619 Vehicle: 0/02 GC/BUGeye WHITE/black	car bogs at 2500 rpm i was wondering if any of u has a clue of what's going on. i have a GC8 w/ a WRX motor and tranny. when it hits 2500 rpm the car bogs. it feels like it will stall. it's like driving a stick for the 1st time. after it passes 2700 rpm it's back to normal. any suggestions? thankx....... KINGSKY * Registered users of the site do not see these ads.

05-19-2003, 04:46 PM	#17
stimpy Homicidal Maniac Moderator Member#: 1612 Join Date: Jun 2000 Location: Austin, TX Vehicle: 2008 STI	Ah, ok. That makes sense then. Was this the 9lb flywheel or the 12lb flywheel? This is actually one of the mods I was seriously considering for my swap (the 12lb flywheel that is). In a different post in the FFI forum, a vendor mentioned that they had to actually raise the idle rpm by a few hundred to resolve the issue. What was happening was the decel was happening too fast for the IAC valve to catch it properly. Stumbling was supposed to be one of the byproducts of this. -Jon Last edited by stimpy; 05-19-2003 at 06:08 PM.

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05-06-2003, 07:22 PM	#2
RimRockaz Scooby Specialist Member#: 2947 Join Date: Nov 2000 Location: El Cerrito, CA Vehicle: 2000 GC6 ej20 swap fast n furious pt III	what are your mods? I had that experience when I first put in the BOV and LINK ECU. After getting rid of the BOV and tune the ECU, the car runs fine..

05-07-2003, 12:53 PM	#3
KINGSKY Scooby Specialist Member#: 31154 Join Date: Dec 2002 Location: SUNNYDIEGO 619 Vehicle: 0/02 GC/BUGeye WHITE/black	all i have is a jun flywheel, upgraded clutch, samco IC hoses, jic xhaust. i think the problem is in ECU. i also have a CEL, with the error code of MISFIRE on all cylinders. thankx 4 the info....... KINGSKY

05-07-2003, 01:12 PM	#4
Shag-e Scooby Specialist Member#: 8168 Join Date: Jul 2001 Chapter/Region: Tri-State Location: Rochester, NY Vehicle: 2013 WRX Limited White	Sounds like bad gas..... Is this common or something new?

05-07-2003, 01:57 PM	#5
KINGSKY Scooby Specialist Member#: 31154 Join Date: Dec 2002 Location: SUNNYDIEGO 619 Vehicle: 0/02 GC/BUGeye WHITE/black	it's not the gas. my car recently had the swap done and it hesitated right off the bat. KINGSKY

05-07-2003, 02:03 PM	#6
Shag-e Scooby Specialist Member#: 8168 Join Date: Jul 2001 Chapter/Region: Tri-State Location: Rochester, NY Vehicle: 2013 WRX Limited White	Well, I had a similar problem when I had my WRX, but it was bad till i hit 5K rpm. It was deduced down to bad grounding on the engine. Added bigger wiring and the problem went away. Its worth a shot and it doesn't cost that much to fix. Search under grounding mod to find out what I am talking about. Hopefully that helps

05-08-2003, 01:22 PM	#8
Coati Scooby Guru Member#: 9106 Join Date: Aug 2001 Chapter/Region: SCIC Location: 10 Doors, 2 Scoops! Vehicle: 2002 WRX Wagon - PSM 2008 STI - Aspen White	It's quite possible that the CEL is due to the JUN being very light (is is the lightweight or the ultralight?). This confuses the ECU, but there is no real misfire. This happened when I had a JUN in my WRX. For all I know, you have my old flywheel.

05-13-2003, 07:19 PM	#9
luvmyrs Scooby Specialist Member#: 1048 Join Date: Mar 2000 Chapter/Region: Tri-State Location: the barnyard Vehicle: 2000 Nothing, thanks to POS thieves.	one of the Tri-State members over here just did the same swap, he had some of the same symptoms as you. What it eventually came down to was a bad ECU. Try to see if someone local is willing to let you test with theyre ECU. If you wanna see the whole saga do a search on the username "Nizz". Goodluck with your project. Frank

05-14-2003, 09:36 AM	#10
Puckaveli Scooby Specialist Member#: 1518 Join Date: May 2000 Location: Stow, OH Vehicle: 00 2.5RS Silver	What is your boost gauge showing at the time of the bog? Some VW's will actually boost faster than the ECU can keep up. The boost will surge then the ECU turns it back for a second. I doubt that's it but who knows.

05-14-2003, 05:07 PM	#11
stimpy Homicidal Maniac Moderator Member#: 1612 Join Date: Jun 2000 Location: Austin, TX Vehicle: 2008 STI	Sounds kind of like the wiring may be suspect. I'd try to confirm the wiring first. If that looks ok, then see if you can borrow an ECU from somebody else and see if that is bad. I've also heard of a misfire being thrown due to a lightweight flywheel, but I haven't heard about it having adverse affects. Did you do the swap or did you pay somebody to do it? -Jon

05-17-2003, 10:00 PM	#12
KINGSKY Scooby Specialist Member#: 31154 Join Date: Dec 2002 Location: SUNNYDIEGO 619 Vehicle: 0/02 GC/BUGeye WHITE/black	problem solved. changed the rear diff and changed out the whole tranny. no more CEL, no more hesitation. hey andrew, thankx dude... KINGSKY

05-18-2003, 05:16 AM	#13
STi-Nismo Dood Scooby Specialist Member#: 4149 Join Date: Feb 2001 Chapter/Region: SCIC Location: Frisco/Diego/LosAngeles Vehicle: MY93 ImprezaRA Sedan GC8.6 Aspen White	how did the tranny make you pull CELs?

05-18-2003, 08:23 PM	#14
KINGSKY Scooby Specialist Member#: 31154 Join Date: Dec 2002 Location: SUNNYDIEGO 619 Vehicle: 0/02 GC/BUGeye WHITE/black	i had a JUN ultralight flywheel, i guess that's the cause.

05-19-2003, 01:07 PM	#15
stimpy Homicidal Maniac Moderator Member#: 1612 Join Date: Jun 2000 Location: Austin, TX Vehicle: 2008 STI	So are you still running the ultralight flywheel? It sounds odd that if you replaced the tranny/rear diff and kept the FW then your CEL was being caused by something other than the FW. -Jon

05-19-2003, 04:20 PM	#16
KINGSKY Scooby Specialist Member#: 31154 Join Date: Dec 2002 Location: SUNNYDIEGO 619 Vehicle: 0/02 GC/BUGeye WHITE/black	stock clutch/flywheel are being used.... no more JUN.

05-19-2003, 07:07 PM	#18
Cacophony Scooby Newbie Member#: 213 Join Date: Aug 1999 Location: Philly, PA Vehicle: 2004 Mazda RX-8 Black	Is this for real? I had an 11lb unorthodox racing flywheel in my 2.5RS and never had a problem. Now that it's an STi V, there's a JUN ultralight in there. I don't have a stock ecu but I don't have any idle problems either...

05-19-2003, 07:11 PM	#19
stimpy Homicidal Maniac Moderator Member#: 1612 Join Date: Jun 2000 Location: Austin, TX Vehicle: 2008 STI	I hadn't heard of it on anything before recently. I know of a WRX and an RS using the 12lb JUN flywheels without a problem. If you remember the fellow on here by the name of efoo, well his Tec 2 couldn't handle his lightweight flywheel and the car would die due to the IAC not catching it quick enough. That is the only other time I can remember a problem. I have heard of lightweight underdrive pulleys throwing misfire codes due to the lack of the balancer though. Could it be that the flywheel was causing misfire codes due to an imperfection in it? Just throwing out ideas here... -Jon

05-20-2003, 04:15 AM	#20
STi-Nismo Dood Scooby Specialist Member#: 4149 Join Date: Feb 2001 Chapter/Region: SCIC Location: Frisco/Diego/LosAngeles Vehicle: MY93 ImprezaRA Sedan GC8.6 Aspen White	my friend once told me that Sports Compact Car did an article on a stock pulley v. the Unorthodox pulley and found that the harmonic balancer did as well as the stock's through their tests... dunno what kind of car though.

05-20-2003, 06:43 PM	#21
stimpy Homicidal Maniac Moderator Member#: 1612 Join Date: Jun 2000 Location: Austin, TX Vehicle: 2008 STI	I've heard conflicting opinions on that. There are many proponants of the stock harmonic dampener on inline fours. However, the flat four is very well balanced. Last time I checked, Trey Cobb and Christian ( Modern Garage) both were against the underdrive pulleys. Shiv used to be against them but after about 2 years, he started selling his own version. -Jon