Welcome to the North American Subaru Impreza Owners Club Thursday December 25, 2014
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 07-22-2003, 01:30 AM   #1
botboy
Scooby Newbie
 
Member#: 40393
Join Date: Jul 2003
Vehicle:
1985 MB 300DT
Maroon

Question 2000 OB, Rough idle-1800 RPM, HELP PLEASE!

Prologue:

My friend Geoff's dad was driving the subaru, a 2000 outback with the 2.5RS, back from his fathers funeral, when they stopped at a gas station to fill up having just gotten off the freeway. He noticed some nasty noise and parked the car, and got a different ride home. The next day he called me and told me what happened, and called me out to see if I could figure out what was wrong. I went out and listened to the car, which had a noise that sounded like a bad rod bearing, but was too far right to be a rod bearing. I went back for the truck and trailer and brought the car home, pulled the engine, and found that the right side head had broken the cam. Further investigation found that the car had been long overdue for an oil change and that side must've gotten really hot and seized part of the cam, and broke it in the middle. Drain the oil and there aren't any specs of metal or anything in it, pulled the other head too, pistons feel tight so there shouldn't be a bad rod bearing. So I got a replacement head for the side that screwed itself up, new intake/head/exhaust gaskets and I reassemble the engine. Replace spark plugs, drop back in car, fill with oil, coolant, top off ATF, put accessories back on.

Now:
Car doesn't have any of the noise it once had with the broken cam (thank god it sounded downright awful) or any valvetrain noise at all. Car does however have a really rough idle and shakes, not violently but it is very annoying. The air filter and box assembly is back on the car too. It got a seafoam treatment which made it smoke but doesn't have any smoke coming from the exhaust once that burned off. Above about 1800 RPM with no load it all smoothes out and doesn't vibrate anymore. I took the car out for a spin and it accelerates pretty nice but killed when I brake down under about 10 MPH, so I restarted it, put a little pedal in and whipped a U turn and went home. Temperature stayed right in the middle, car had about 1/4 tank of 91 octane when I did all this. Even after getting home the engine still idled real rough and would not stay in one place for idle, would instead tend to fluxuate between 500-1100 RPM. Putting on the A/C caused the fans to come on and the air bypass valve to actuate, and the idle went up but was still a bit rough. The check engine light has yet to come on.

Compressed version:
2000 outback broke cam (engine 2.5 4-cyl, Automatic)
I replaced that side head and reassembled engine
put engine back in car
now engine idles real rough at about 900-1100 RPM, above 1800 the engine smoothes out and doesn't vibrate.
Car died when I took it for a quick test drive and slowed down to whip a U turn.
No lights are on indicating a problem on the dashboard

Attempted fixes:
Took battery cables off for 5 mins, didn't seem to accomplish anything.

Checked and double checked engine timing, it is correct and directional arrow on new belt is pointed in the right direction. All sensors, wires, and connections are reconnected to their correct place and secured.

Also:
I cut apart the oil filter to see how much damage this could have inflicted had the oil filter caught something that I wasn't seeing in the oil I drained out...nada, nothing in the oil filter either. My guess is that since the right head wasn't getting too much oil in, it probably wasn't putting out much (if any) tainted oil.
* Registered users of the site do not see these ads.
botboy is offline   Reply With Quote
Old 07-22-2003, 10:07 AM   #2
tmat3
Scooby Specialist
 
Member#: 2817
Join Date: Nov 2000
Location: NYC and Troy, NY
Vehicle:
2001 Impreza 2.5RS
BRP

Default

Hi,

A few things come to my mind:

1) leaking or disconnected vacuum line somewhere.
2) EGR value may be dead.
3) Fuel filter or injectors may be clogged. Or, engine may not be getting enough fuel pressure.
4) Manifold Absolute Pressure sensor may be faulty or disconnected.
5) You said timing is ok. So, at TDC, the camshaft is at the correct place, right?
6) Faulty IAC??

I'm just throwing possibilities....
tmat3 is offline   Reply With Quote
Old 07-22-2003, 11:30 AM   #3
kickin_81
Scooby Newbie
 
Member#: 16679
Join Date: Mar 2002
Location: MN
Vehicle:
2004 Forester XT

Default

After you have secured everything, remember to do a full (1 hour +) ECU reset.
kickin_81 is offline   Reply With Quote
Old 07-22-2003, 02:34 PM   #4
CheezeWeezle
Scooby Specialist
 
Member#: 17187
Join Date: Apr 2002
Chapter/Region: BAIC
Location: Fresno, CA
Vehicle:
2009 Braun Entervan
Gimpy White

Default

Quote:
Originally posted by tmat3
Hi,

A few things come to my mind:

1) leaking or disconnected vacuum line somewhere.
2) EGR value may be dead.
3) Fuel filter or injectors may be clogged. Or, engine may not be getting enough fuel pressure.
4) Manifold Absolute Pressure sensor may be faulty or disconnected.
5) You said timing is ok. So, at TDC, the camshaft is at the correct place, right?
6) Faulty IAC??

I'm just throwing possibilities....
As a quick cheap start...I would go to number 3 on his list and check the fuel filter. If they hadn't changed the oil in awhile...chances are they haven't done anything else to the car either.
CheezeWeezle is offline   Reply With Quote
Old 07-22-2003, 02:45 PM   #5
botboy
Scooby Newbie
 
Member#: 40393
Join Date: Jul 2003
Vehicle:
1985 MB 300DT
Maroon

Default

Quote:
Originally posted by CheezeWeezle


As a quick cheap start...I would go to number 3 on his list and check the fuel filter. If they hadn't changed the oil in awhile...chances are they haven't done anything else to the car either.
The Fuel filter is pretty new, less than 10k on it. I can replace it if necessary but that doesn't explain why the engine smoothes out above 1800 RPM....
botboy is offline   Reply With Quote
Old 07-22-2003, 02:47 PM   #6
botboy
Scooby Newbie
 
Member#: 40393
Join Date: Jul 2003
Vehicle:
1985 MB 300DT
Maroon

Default

I should also note that before the cam broke and the engine was rebuilt the car had none of the idling problems it has now...
botboy is offline   Reply With Quote
Old 07-22-2003, 06:15 PM   #7
BOY
NASIOC Supporter
 
Member#: 232
Join Date: Sep 1999
Chapter/Region: MWSOC
Location: Ft Wayne, IN
Vehicle:
99 RS-T RIP
02 Forster-S

Default

plugs/wires? You're SURE the cam timing is correct? Valves lashed too tightly?
BOY is offline   Reply With Quote
Old 07-22-2003, 11:29 PM   #8
CheezeWeezle
Scooby Specialist
 
Member#: 17187
Join Date: Apr 2002
Chapter/Region: BAIC
Location: Fresno, CA
Vehicle:
2009 Braun Entervan
Gimpy White

Default

Quote:
Originally posted by BOY
plugs/wires? You're SURE the cam timing is correct? Valves lashed too tightly?
Then these are the next cheap things I would look at....I'm looking cheap here!!! ....well sorta....
CheezeWeezle is offline   Reply With Quote
Old 07-23-2003, 05:15 PM   #9
brandon
Scooby Newbie
 
Member#: 1183
Join Date: Mar 2000
Vehicle:
2002 Legacy L SE Wag
1964 Lotus Elan

Default

Okay, I'll play the devil's advocate here and ask the dumb question just in case. I didn't notice you saying specifically that the engine in the Outback had ever been been replaced previously. Is this a regular Outback or an Outback Sport? The 2000 Outback Sport came from the factory with a 2.2L rather than a 2.5L. In which case the head from a 2.5L would be letting in way too much air.
This was just a shot in the dark, so please don't be insulted. I couldn't tell if it was your car or not. You seem quite knowledgeable, but if someone else mistakenly told you the wrong engine size...
brandon is offline   Reply With Quote
Old 07-25-2003, 03:32 AM   #10
botboy
Scooby Newbie
 
Member#: 40393
Join Date: Jul 2003
Vehicle:
1985 MB 300DT
Maroon

Default

Quote:
Originally posted by brandon
Okay, I'll play the devil's advocate here and ask the dumb question just in case. I didn't notice you saying specifically that the engine in the Outback had ever been been replaced previously. Is this a regular Outback or an Outback Sport? The 2000 Outback Sport came from the factory with a 2.2L rather than a 2.5L. In which case the head from a 2.5L would be letting in way too much air.
This was just a shot in the dark, so please don't be insulted. I couldn't tell if it was your car or not. You seem quite knowledgeable, but if someone else mistakenly told you the wrong engine size...
Nope, I dont take offense...Its not an outback sport and its got a NA 2.5L, says EJ2.5 on a plate on the engine too as well as various 2.5 references on the hood and in the manual.

I pulled the oil pan today and rotated the torque converter 90 degrees which helped a little but there is still some vibration I don't especially like, I may try all four positions with the torque converter in case that is the problem.

Also it isn't my car, its a friends parents car and they use me as their regular mechanic because I undercut local mechanics and use my dads tools to avoid overhead and make myself some good cash fixing cars in the area.
botboy is offline   Reply With Quote
Old 07-25-2003, 03:41 AM   #11
CheezeWeezle
Scooby Specialist
 
Member#: 17187
Join Date: Apr 2002
Chapter/Region: BAIC
Location: Fresno, CA
Vehicle:
2009 Braun Entervan
Gimpy White

Default

I guess the next question would be does it feel like a "warble" or does it idle like it wants to die?...After reading it again...and after your torque converter rotation I see you say it idles rough still?....Not to sound ignorant and it took me awhile to get used to it was that fact that it is a boxer engine and does vibrate funny.....

And how about those plugs...didn't see you comment on that yet?...Hope you have got it fixed!
CheezeWeezle is offline   Reply With Quote
Old 07-26-2003, 06:23 PM   #12
botboy
Scooby Newbie
 
Member#: 40393
Join Date: Jul 2003
Vehicle:
1985 MB 300DT
Maroon

Default

Update: Still no luck

Rotating the torque converter helped a little but didn't fix it yet. Its definitely not a normal vibration. And I've got a new discovery that hasn't fixed the problem but may give some insight into the problem.

If I pull the number 1 or 3 spark plugs (right head), the engine doesn't respond at all, no change in RPM's or anything. Pulling 2 or 4 (left head) will make the engine drop several hundred RPM's and sound like its going to die. I tested the injectors on 1 and 3 and they both work fine, and there is plenty of spark on the 1 and 3 cylinders (shocked myself learning that one!). I (again) retimed the engine but am still having the same problems, so I think it may be a timing issue, I'm just not sure how to go about fixing it. It's the same head as the one that broke, I compared them side to side prior to installing the new used one, and they look exactly the same, same combustion chamber, same size valves, etc, so I'm not sure what to do now. I'm going to go borrow a friends compression tester to see if that turns out to be my problem. The head came off of a 2000 Impreza that was in a wreck, is there any possibility that the timing was somehow different between the cams in the two? I didn't get the cam gear with the junkyard head so I switched them but I am now beginning to wonder if the gears are any different.

Edit: in response to above post the spark plugs are new NGK splitfires exactly like were in the car prior to it breaking.
botboy is offline   Reply With Quote
Old 07-26-2003, 07:30 PM   #13
botboy
Scooby Newbie
 
Member#: 40393
Join Date: Jul 2003
Vehicle:
1985 MB 300DT
Maroon

Default

Update again:
Got a compression tester from dad, results are as follows:

Cylinder
1: ~5
2:~155
3:~5
4:~155

Squirting oil into the #1 & 3 cylinders yielded similar results. I know that there isn't a chance the rings are that bad on this car, even with 96k and squirting oil in the cyls should have improved compression drastically, so I think that I narrowed it down to two problems:

1) Valves aren't adjusted properly
2) Major timing issue/problem

I'm now off to adjust valves and hope to god it fixes everything. Wish me luck!
botboy 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
Rough idle, intermitent and rough cold starts... carter_wrx Pre-2002 Factory Turbo Powertrain 26 10-28-2009 02:03 PM
800 hp @ 2500 rpm, 2200 lb-ft @ 1800 rpm Reciprocity Off-Topic 34 12-21-2004 01:56 PM
Rough idle, lack of power under 2k rpm... madsedan Forester Forum 2 05-19-2004 11:47 PM
Rough idle and high-pitched whine at high RPMs fastenova Legacy Forum 10 11-21-2003 03:50 PM
Rough idling, hesitation at about 4000 rpm MadManMike General Community 3 07-04-2002 02:47 PM


All times are GMT -4. The time now is 05:33 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.