Welcome to the North American Subaru Impreza Owners Club Thursday July 2, 2015
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC Technical > Normally Aspirated Powertrain

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 04-03-2005, 04:56 PM   #1
powerlabs
Scooby Specialist
 
Member#: 45790
Join Date: Oct 2003
Chapter/Region: Tri-State
Location: New Jersey
Vehicle:
2006 Corvette C6 Z51
SUPERCHARGED

Default Ticking / slapping sound coming from engine; help please. W/VIDEO

It seems like every week there is something new that goes wrong with my car and I have to sink further into credit card debt fixing it.
This time; I got the car back from my latest repair (MAF went) and it was running fine. Drove 100 miles with it, then on my drive back I noticed that at partial throttle (10 - 20% to be exact) the engine makes a ticking / slapping sound. It sounds exactly like a lawnmower. It idles fine and does not make any unusual sounds when idling, and it also does not make any unusual sounds when at higher throttle settings. Power appears to be normal. I believe the sound may have started after I drove the car very fast for an extended period of time, but I am not 100% sure.
I made a video of the engine with the hood open and me manually opening the throttle. You can clearly hear the sound I am talking about on the video, and you can also see how the sound goes away when the engine is idling or at WOT.
It will make this sound at any RPM, but only at 10 / 20% throttle, and it has never done this before. The engine is fully warmed up when it does it also.
I have a perma-CEL from my high flow cat. converter, DESPITE the GP Moto rip-off CEL fix, but aside from that I do not believe this is causing any more CELs.
I hope that this is nothing serious and that some of the more knowledgeable members here might be able to help me solve this issue without having to take the car to a dealership because I really can not afford it right now. Thanks guys.
* Registered users of the site do not see these ads.

Last edited by powerlabs; 04-04-2005 at 10:58 AM. Reason: Maybe the video will help?
powerlabs is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 04-03-2005, 06:47 PM   #2
Slack
Scooby Specialist
 
Member#: 17548
Join Date: Apr 2002
Location: Atlanta, Ga
Default

Damn! That does not sound good AT ALL. The sound made me cringe. I'm no mechanic, but it sounds like pistons hitting valves. I could be completely wrong, though. I would strongly recommend not driving it any more until you figure it out. I will pm Tim Sanderson to make sure he reads this thread.


Mick
Slack is offline   Reply With Quote
Old 04-03-2005, 06:55 PM   #3
powerlabs
Scooby Specialist
 
Member#: 45790
Join Date: Oct 2003
Chapter/Region: Tri-State
Location: New Jersey
Vehicle:
2006 Corvette C6 Z51
SUPERCHARGED

Default

Yeah, it sounds horrible, but I still had to drive it back 100 miles like that. As I said though, it only does it at 10 - 20% throttle, so if I go from no gas to halfway down on the gas pedal, the car sounds normal.
More info on the car that may be relevant: Subaru Impreza 2.5RS 1999, 79000miles, running Mobil 1 synthetic, 2500miles since last oil change. The sound appears to come from either the throttle body or from the passenger side of the engine, but that may just be my impression. Mods are a full exhaust (Borla Headers / random tech high flow cat converter, borla catback), Injen CAI, UD pulley, LW Flywheel, Apexi S-AFC, PLX devices Wideband O2. A/F Ratio is normal when the car makes that sound. The car is driven hard, but it has never made that sound before.
powerlabs is offline   Reply With Quote
Old 04-03-2005, 06:58 PM   #4
Slack
Scooby Specialist
 
Member#: 17548
Join Date: Apr 2002
Location: Atlanta, Ga
Default

Have you ever had the valves adjusted? Have you replace the timing belt? How about the timing belt tensioner? I know you had an accident in your car a while back...was the timing belt cover cracked or damaged at all?


Mick
Slack is offline   Reply With Quote
Old 04-03-2005, 07:14 PM   #5
powerlabs
Scooby Specialist
 
Member#: 45790
Join Date: Oct 2003
Chapter/Region: Tri-State
Location: New Jersey
Vehicle:
2006 Corvette C6 Z51
SUPERCHARGED

Default

Quote:
Originally Posted by Slack
Have you ever had the valves adjusted? Have you replace the timing belt? How about the timing belt tensioner? I know you had an accident in your car a while back...was the timing belt cover cracked or damaged at all?


Mick
The valve cover on this car has never been off AFAIK. Timing belt replacement is scheduled every 100K miles by Subaru, so I haven't done that yet either. Same for the timing belt tensioner.
As per the repair shop bill it does not seem like there was any damage done to the engine or the timing belt cover. Also, it has been some 10 000miles since my accident and this noise never occured before.
powerlabs is offline   Reply With Quote
Old 04-04-2005, 03:33 PM   #6
powerlabs
Scooby Specialist
 
Member#: 45790
Join Date: Oct 2003
Chapter/Region: Tri-State
Location: New Jersey
Vehicle:
2006 Corvette C6 Z51
SUPERCHARGED

Default

Help? Someone?
powerlabs is offline   Reply With Quote
Old 04-04-2005, 04:31 PM   #7
Jejunum
Scooby Specialist
 
Member#: 15773
Join Date: Feb 2002
Chapter/Region: MWSOC
Location: Madison
Vehicle:
2011 Impreza WRX
Silver

Default

u should get timing belt tensioner replaced and see if that does it. if thats whats wrong it will be visually apparent when replacing it too (so im told)
Jejunum is offline   Reply With Quote
Old 04-04-2005, 04:57 PM   #8
X4 SRT
Scooby Newbie
 
Member#: 40636
Join Date: Jul 2003
Location: Las Vegas
Vehicle:
2001 2.5 RS Coupe
Silver

Default

I agree with the timing belt theory. Get it replaced and do it quick.
X4 SRT is offline   Reply With Quote
Old 04-04-2005, 05:07 PM   #9
CirrusWRX
Scooby Guru
 
Member#: 17439
Join Date: Apr 2002
Chapter/Region: Tri-State
Location: Yardley, PA
Vehicle:
2002 x2 Silver WRX
Sedan, White WRX Wagon

Default

I was under the impression RS's were due to have timing belts replaced at 60,000 miles - I'm not an RS owner, but that's what I have heard. Obviously, the owners manual would be a good source, and please correct me as there is a very good chance I'm talking out of my arse.
CirrusWRX is offline   Reply With Quote
Old 04-04-2005, 05:54 PM   #10
DreddRS25
Scooby Specialist
 
Member#: 51642
Join Date: Dec 2003
Chapter/Region: TXIC
Location: San Antonio, Texas
Vehicle:
2001 Impreza RS
BRP

Default

I think it sounds like the Butterfly fluttering in the TB. It seems to react immediately when you get on and off the throttle.

May try revving it for a moment with the airbox off. Have a look at the butterfly while changing the throttle position. (not best idea, but if it is the TB it will be much louder without the airbox) Maybe even just take the back part of the airbox off?

GL!
DreddRS25 is offline   Reply With Quote
Old 04-04-2005, 06:33 PM   #11
Nicklbrso
Scooby Specialist
 
Member#: 44887
Join Date: Oct 2003
Chapter/Region: NESIC
Location: ME
Vehicle:
00 GC6
Silver

Default

Quote:
Originally Posted by CirrusWRX
I was under the impression RS's were due to have timing belts replaced at 60,000 miles - I'm not an RS owner, but that's what I have heard. Obviously, the owners manual would be a good source, and please correct me as there is a very good chance I'm talking out of my arse.
No. The timing belt is scheduled maintenance at 105K miles.
Nicklbrso is offline   Reply With Quote
Old 04-04-2005, 06:39 PM   #12
jamesonc
Scooby Newbie
 
Member#: 49629
Join Date: Dec 2003
Chapter/Region: NESIC
Location: Southern Maine
Vehicle:
'87 Dodge Ram 50
Black

Default

It could also be something like lifter tick. Is it a loud noise?
jamesonc is offline   Reply With Quote
Old 04-04-2005, 06:56 PM   #13
powerlabs
Scooby Specialist
 
Member#: 45790
Join Date: Oct 2003
Chapter/Region: Tri-State
Location: New Jersey
Vehicle:
2006 Corvette C6 Z51
SUPERCHARGED

Default

Check out the video. It is quite loud; makes my engine sound exactly like a push type lawnmower. I don't see how replacing the timing belt would help since the engine only does it at part throttle; if it was a timing issue it would do it at all throttle settings, no?
powerlabs is offline   Reply With Quote
Old 04-05-2005, 11:50 AM   #14
DreddRS25
Scooby Specialist
 
Member#: 51642
Join Date: Dec 2003
Chapter/Region: TXIC
Location: San Antonio, Texas
Vehicle:
2001 Impreza RS
BRP

Default

Check the exhaust from the bottom of the motor?

Maybe an exhaust leak at the headers?
DreddRS25 is offline   Reply With Quote
Old 04-05-2005, 12:12 PM   #15
powerlabs
Scooby Specialist
 
Member#: 45790
Join Date: Oct 2003
Chapter/Region: Tri-State
Location: New Jersey
Vehicle:
2006 Corvette C6 Z51
SUPERCHARGED

Default

Only a part throttle though? An exhaust leak would get louder when you applied more throttle, I think; this noise goes away after 20% throttle.
But no, its not the exhaust
powerlabs is offline   Reply With Quote
Old 04-05-2005, 01:26 PM   #16
Tim Sanderson
Scooby Guru
 
Member#: 6486
Join Date: May 2001
Chapter/Region: MWSOC
Location: S.E. wisconsin
Vehicle:
00 Impreza 2.5 RS
Blue Ridge Pearl

Default

My computer sucks so I can't hear or see the vid.

Where are you located? How far is that from Milwaukee?
Tim Sanderson is offline   Reply With Quote
Old 04-05-2005, 01:29 PM   #17
powerlabs
Scooby Specialist
 
Member#: 45790
Join Date: Oct 2003
Chapter/Region: Tri-State
Location: New Jersey
Vehicle:
2006 Corvette C6 Z51
SUPERCHARGED

Default

Quote:
Originally Posted by Tim Sanderson
My computer sucks so I can't hear or see the vid.
Well, it just shows a close up of my engine idling; it sounds normal. Then I give it a little bit of gas and it will start to rev and sound exactly like a push type lawnmower. Giving it more gas makes it rev up and sound normally. It only makes the ticking / slapping / knocking / whatever sound at exactly 10 / 20% throttle position, regardless of gear or speed. The sound seems loudest at the intake.

Quote:
Where are you located? How far is that from Milwaukee?
UP Michigan; about 5 hours south of Milwaukee.
powerlabs is offline   Reply With Quote
Old 04-05-2005, 02:06 PM   #18
HndaTch627
Scooby Guru
 
Member#: 6551
Join Date: May 2001
Chapter/Region: MWSOC
Location: Carol Stream, IL
Vehicle:
'01 GC8 Dinged STM
'09 Concours 14 ABS Black

Default

see your midwest thread for my response
HndaTch627 is offline   Reply With Quote
Old 04-05-2005, 05:34 PM   #19
powerlabs
Scooby Specialist
 
Member#: 45790
Join Date: Oct 2003
Chapter/Region: Tri-State
Location: New Jersey
Vehicle:
2006 Corvette C6 Z51
SUPERCHARGED

Default Update.

OK, I got the car up on ramps and looked all over it.
No exhaust leaks, no cracks on the exhaust headers, no oil drips or liquids pooling up under the car.
Passenger side heads have a little bit of clear oil around them. I don't think it is a leak.
The sound appears to be louder from the top of the engine. It seems to come from the intake almost.
Still no solutions. Someone must have gone through a similar situation before or know what to do, no?
powerlabs is offline   Reply With Quote
Old 04-05-2005, 05:38 PM   #20
DreddRS25
Scooby Specialist
 
Member#: 51642
Join Date: Dec 2003
Chapter/Region: TXIC
Location: San Antonio, Texas
Vehicle:
2001 Impreza RS
BRP

Default

Quote:
Originally Posted by DreddRS25
I think it sounds like the Butterfly fluttering in the TB. It seems to react immediately when you get on and off the throttle.

May try revving it for a moment with the airbox off. Have a look at the butterfly while changing the throttle position. (not best idea, but if it is the TB it will be much louder without the airbox) Maybe even just take the back part of the airbox off?

GL!
Have you ruled out the TB?

Look inside the TB through the airbox inlet with motor running and watch the butterfly as you change the throttle position.
DreddRS25 is offline   Reply With Quote
Old 04-05-2005, 08:09 PM   #21
powerlabs
Scooby Specialist
 
Member#: 45790
Join Date: Oct 2003
Chapter/Region: Tri-State
Location: New Jersey
Vehicle:
2006 Corvette C6 Z51
SUPERCHARGED

Default

How can I do that?; if I want to look at my throttle butterfly I will need to disconnect the MAF and the car will not run.
powerlabs is offline   Reply With Quote
Old 04-06-2005, 06:31 PM   #22
DFL2.5RS
Scooby Specialist
 
Member#: 73228
Join Date: Oct 2004
Chapter/Region: MWSOC
Location: Michigan
Vehicle:
2015 White STI
2013 WRX, 2003 Rally car

Default

your car should still run if you have the maf unplugged I believe...
DFL2.5RS is offline   Reply With Quote
Old 04-07-2005, 09:24 AM   #23
DreddRS25
Scooby Specialist
 
Member#: 51642
Join Date: Dec 2003
Chapter/Region: TXIC
Location: San Antonio, Texas
Vehicle:
2001 Impreza RS
BRP

Default

Quote:
Originally Posted by powerlabs
How can I do that?; if I want to look at my throttle butterfly I will need to disconnect the MAF and the car will not run.
It would help if I looked at the year of your make.

I often forget the difference between a MAF and MAP. Though, I thought the car would run upto 4k rpms without the MAF plugged in. Not sure how easy or necessary that would be, but I would try it (though having a mechanic look at it would be best).
DreddRS25 is offline   Reply With Quote
Old 04-07-2005, 10:47 AM   #24
Siper2
Scooby Guru
 
Member#: 1134
Join Date: Mar 2000
Chapter/Region: MAIC
Location: Dillsburg, PA
Vehicle:
2007 BMW 328xi wagon
Silver

Default

Timing belt tensioner, perhaps? Mine went at about 65k I think.... replaced the belt while they were at it.

That was a loud, very obvious WHAP WHAP WHAP though. Not much like a lawnmower... unless it was a sick one...
Siper2 is offline   Reply With Quote
Old 04-07-2005, 11:01 AM   #25
John*G
Scooby Specialist
 
Member#: 19562
Join Date: Jun 2002
Chapter/Region: NESIC
Location: VT
Vehicle:
95 coupe
red

Default

That does not sound like a timing belt tensioner, I replaced mine. It kind of sounds like a alternator with a bad brush. If you have a piece of tube/pipe, or better yet a stethoscope it may help pin point the source of the noise.
John*G is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Loud ticking noise coming from motor. Help prestofilipo Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) 35 12-17-2011 10:17 PM
Odd sound coming from brake/suspension? Help! Leo has WRX Brakes, Steering & Suspension 0 06-15-2008 02:19 AM
Knocking sound coming from passenger front...help EL CABRON Factory 2.5L Turbo Powertrain (EJ Series Factory 2.5L Turbo) 0 05-01-2008 09:27 AM
Ticking? Rattling Sound coming from rear of car??! enXiks Newbies & FAQs 3 08-24-2006 06:59 AM
help! sound coming from front right tire dodichi Brakes, Steering & Suspension 3 05-28-2001 07:54 PM


All times are GMT -4. The time now is 03:44 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2015 Axivo Inc.
Copyright ©1999 - 2015, North American Subaru Impreza Owners Club, Inc.