very rough idle.....

stant093 · Post by **stant093** » Sun Feb 22, 2004 1:54 pm

hey everyone my car is running really rough.....when idoling it almost seems like its skipping.....in may i replaced the engine or somewhere around there, along with fuel filter air filter and plugs/wires......today i stopped in traffic at a stop sign and the freakin thing stalled on me....when letting it idol, it idols at 1.5K RPM, it should be at 700, like it allways has been....
and when it decides it wants to idol at 700 it is real rough as if its skipping...any ideas?

today i changed oil and plugs, no effect...... any clues, somebody mentioned vaccume lines maybe?

THAWA · Post by **THAWA** » Sun Feb 22, 2004 3:00 pm

have you checked your iac valve yet? That's usually the culprit.

stant093 · Post by **stant093** » Sun Feb 22, 2004 3:31 pm

i havent yet, how easy is it to clean that? and stupid question, where exactly is it located? a pic possibally..or something? ive never had this happen b4, so i havent ever messed with an IAC

edit: i did some searching and found this pic:
http://www.main.experiencetherave.com:8 ... P_2470.JPG

hopefully i can just swap it out as i have another intake setup already banging around

J-MoNeY · Post by **J-MoNeY** » Sun Feb 22, 2004 10:48 pm

THAWA wrote:have you checked your iac valve yet? That's usually the culprit.

What is the IAC valve? Mine is idling weird too.

stant093 · Post by **stant093** » Mon Feb 23, 2004 12:27 am

well i took it apart and cleaned it the best i could, maybe a 10% improvement, but i dont think thats it...the thing didnt look dirty and everything moved around freely.....next step plug wires, and fuel filter

vrg3 · Post by **vrg3** » Mon Feb 23, 2004 1:06 am

Maybe get a can of starting fluid and look for vacuum leaks? If you need pointers on how to do it, search for "starting fluid".

THAWA · Post by **THAWA** » Mon Feb 23, 2004 2:57 am

$J-MoNeY-$ wrote:
THAWA wrote:have you checked your iac valve yet? That's usually the culprit.
What is the IAC valve? Mine is idling weird too.

it's a little valve that opens when the throttle is closed and you are idling. It opens to keep the engine with air so the throttle plate doesn't have to stay opened a little bit. See the pic in stant's post above to see where it is.

stant093 · Post by **stant093** » Tue Feb 24, 2004 1:27 am

ok so after changine everything except the IAC and air filter, no improvement....check engine light keeps coming on

tomorrow im going to have someone who has a little more knowledge take a go at it..this is beginning to worry me now....cant be good for the engine....

vrg3 · Post by **vrg3** » Tue Feb 24, 2004 1:35 am

Did you try the starting fluid thing?

Edit: Oh, you just PM'd me asking about it. :) Just do a search for posts containing the words "starting fluid" with me as author.

stant093 · Post by **stant093** » Fri Feb 27, 2004 8:19 pm

so it turns out its a cracked intake manifold....

apparently when i had the motor put in last fall they messed up the driver side intake installation...i can see a piece of the gasket sticking out and some fresh looking aluminum, looks like an ear that you bolt through is snapped off from the intake on no 4 cylinder.....im waiting on intake manifold gaskets now and am looking to do the job next friday or saturday....i miss having a nice running subaru....

vrg3 · Post by **vrg3** » Fri Feb 27, 2004 8:21 pm

The manifold itself is cracked?! That sucks! That wouldn't have happened easily.

Are you gonna put your spare manifold on in its place? Make sure the mating surface on the heads is clean and flat. Hopefully it didn't get marred or scratched too much when the manifold was damaged.

stant093 · Post by **stant093** » Fri Feb 27, 2004 8:27 pm

i think it was over tightened when i had the wiring harness swapped over.....they pulled it off and did the swap, i wish i wouldve never let em touch the car but i simply didnt have any time to do it

i think having too much pressure over a 6 month time did it...it stil runs and have no choice but to drive it....i know its not good to do but i CAN NOT be without a car right now....i guess its time to invest the time and money into my impreza.....:shrugs:

vrg3 · Post by **vrg3** » Fri Feb 27, 2004 8:34 pm

It won't kill the car. I drove with a leaky manifold gasket for like 10,000 miles, and I have no idea how long the previous owner drove it like that. Now with it fixed you can't tell there was ever a problem.

You should loosen and retorque the other bolts in the meantime. The torque spec is actually pretty low. I think the inner bolts are something like 5 ft-lbs and the outer ones are about 21 ft-lbs.

stant093 · Post by **stant093** » Fri Feb 27, 2004 8:40 pm

yeah good idea, im going to my brothers place this afternoon, shes due for an inspection by the end of the month and they told me the exhaust is too loud, gonna see if i can patch things up for now........so ill use his torque wrench and reset the bolts while im there....im curious what there at now .....i wonder how off they are.....ill get a pic of what i can see is wrong with the intake...hopefully my camera will get a few good ones anyway..

yeah, im gonna take the intake i have and replace it....maybe paint it as i have a week or so to tinker on it....probably take my dremel and clean it up real good....its got some cancer on it as its been sitting for quite some time now....hopefully its good to go...

P.S. i managed to get a free back up IAC valve though

Sam

evolutionmovement · Post by **evolutionmovement** » Sat Feb 28, 2004 12:19 am

You've got to watch those intake manifolds - you don't wantt hem blowing up and taking out your diamond plate floor boards.

Steve

stant093 · Post by **stant093** » Sat Feb 28, 2004 1:32 am

evolutionmovement wrote:You've got to watch those intake manifolds - you don't wantt hem blowing up and taking out your diamond plate floor boards.

Steve

huh??

i pulled some stuff apart to get a better view tonight and it appears that what i thought was a crack was where my friend had wiped the oil off the manifold to give it a new aluminum look, which i inturn thought it was a crack.....well its not

it turns out that the intake manifold gasket blew out....so i can visually see where its sucking air....hopefully this will be an easier fix than i though, any precations i should be aware about when pulling the manifold off besides lefty loosey right tighty?
Thanks guys

vrg3 · Post by **vrg3** » Sat Feb 28, 2004 1:40 am

Oh, phew!

I typed this list from memory a long time ago for subiekid, but it should give you a general idea of what you have to do:

- Unplug fuel pump harness
- Crank engine for a few seconds to relieve fuel pressure
- Remove spark plug wires
- Remove all intake tubing going into the compressor inlet and leaving the compressor outlet
- Plug compressor inlet and outlet with clean rags so stuff doesn't get in them
- Remove battery
- Undo harness connectors behind battery (these lead to the manifold; your car's wiring might be completely different though)
- Undo fuel lines with a rag underneath to catch spilled fuel
- Unplug PCV hose from valve and from heads on either side
- Disconnect power steering vacuum hose
- Disconnect throttle and cruise control cables
- Drain cooling system (that was for the "1"-shaped coolant filler bottle; you may not need to do this)
- Remove coolant filler bottle (again, you don't need to do this)
- Remove drivebelt cover
- Remove power steering/alternator drivebelt
- Siphon out power steering fluid from pump reservoir
- Disconnect power steering lines with a rag underneath to catch fluid
- Remove power steering pump
- Remove alternator
- Undo PCV hose behind alternator
- Unplug ignition coil harness connector
- Unplug cam and crank sensor harness connectors
- Disconnect coolant lines from throttle body and idle air control valve with a rag underneath to catch spilled coolant
- Remove oil filler neck
- Plug oil filler on block with a clean rag
- Remove all eight manifold mounting bolts
- Lift manifold slightly and:
- Unplug wire from coolant temp sensor and coolant gauge sender
- Unclip cam and crank sensor wires from the little plastic clips holding them in place
- Disconnect hoses and harness from the purge control solenoid
- Remove manifold
- Stuff clean rags into intake ports on cylinder head
- Scrape all old gasket material off both mating surfaces with a razor blade, being careful not to let any fall into the intake ports
- Thoroughly clean threads on all bolts with a wire brush and maybe a good soak in alcohol or some sprays with brake cleaner

stant093 · Post by **stant093** » Sat Feb 28, 2004 1:47 am

im wondering if i can get away without pulling the alternator and all the jazz....well see. i take your list into consideration though definatly, Vrg3! thanks man!
Sam

vrg3 · Post by **vrg3** » Sat Feb 28, 2004 1:53 am

No no! That's what I tried to do too, and it just made the job take a lot longer. In the end I still had to remove them. Don't be shy about removing stuff and you'll thank yourself when you finish more quickly with less stress.

Pulling the alternator really only takes a couple minutes at the most. And the power steering lines are kind of in the way, if I remember right, so you have to do most of the work of pulling the power steering pump anyway. A quick note about that -- all the manuals I've seen said to remove the pulley from the pump. That's not necessary. Subaru thoughtfully put holes in the pulley sized perfectly for sticking a socket through to remove the pump mounting bolts without removing the pulley.

Oh, and I should have mentioned that the above list is for turbos, so it'll be a little different on a non-turbo.

evolutionmovement · Post by **evolutionmovement** » Sat Feb 28, 2004 5:37 am

If you're just replacing the gaskets, do you have to remove akll that stuff? what if you just remove the bolts and lift the manifold clear a little so you can switch gaskets out?

The manifold blowing up thing is a stupid reference to Fast & Furious.

Steve

THAWA · Post by **THAWA** » Sat Feb 28, 2004 5:38 am

gah, vrg that's a lot of stuff that doesn't have to be done. I've never drained my ps fluid and I've changed headgaskets, just unbolt the pump and move it to the side. The rubber lines back there are pretty flexible. I'm pretty sure you can get away with just removing the bolts and lifting it up just a smidge to remove the gasket. Do both sides to be sure though. A lot of the coolant/air/fuel lines have lead-way so you can just move the manifold a lil bit. I think you can probably keep the intake plumbing still attached too. But to be safe, you'd wanna do most of what vrg posted.

vrg3 · Post by **vrg3** » Sat Feb 28, 2004 5:55 am

I guess I didn't consider that you could unbolt the power steering pump without removing the lines... When I did it I removed the lines first and then realized later that the pump was in the way.

It's possible that intake piping can stay on a non-turbo, but it definitely wasn't an option on my turbo.

From my experience, it won't do to just lift the manifold up a little. It took a long time to scrape all the old gasket material off, and you can't fit a hand with a razor in and see what you're doing unless you actually separate the manifold from the heads. I suppose you could get away with being sloppy and not cleaning the mating surfaces completely, but I didn't want to take the chance of another leak.

stant093 · Post by **stant093** » Sat Feb 28, 2004 6:17 am

yeah i was thinking of pulling it up just an inch or two with this kid josh, we grew up beating and fixing scoobs since we were 10, and between the two of us we ruled out the lifting idea due to the bad gaskets that were sure wont come off in one piece, i just dont want to have to pull all the belts off, if im going to do that i mine as well get new ones....what else is good for the engine to replace while im tearing it down a little? i figure i have about $100 after the gasket set to help the poor old scoobie out..........

vrg3 · Post by **vrg3** » Sat Feb 28, 2004 6:39 am

Why are you hesitant to remove the power steering/alternator belt? It only takes a couple minutes tops -- just remove the belt cover, undo the tensioner lock bolt, relieve belt tension, and pull it off.

If you do drain the coolant, you'll want to put fresh new coolant in. Couldn't hurt to change the thermostat and maybe the thermostat gasket at the same time. Flush the radiator out too maybe.

You could clean all the gunk out of the PCV hoses that you remove.

If you can spare the cash it might be good to replace some of the mounting bolts rather than just cleaning off and reusing the old ones.

You could replace the fuel filter since you'll be relieving fuel pressure anyway.

I can't really think of much else that is easier to do while changing intake manifold gaskets.

THAWA · Post by **THAWA** » Sat Feb 28, 2004 1:31 pm

stant093 wrote:yeah i was thinking of pulling it up just an inch or two with this kid josh, we grew up beating and fixing scoobs since we were 10, and between the two of us we ruled out the lifting idea due to the bad gaskets that were sure wont come off in one piece, i just dont want to have to pull all the belts off, if im going to do that i mine as well get new ones....what else is good for the engine to replace while im tearing it down a little? i figure i have about $100 after the gasket set to help the poor old scoobie out..........

Will you need all those gaskets though? The set includes the head gaskets, so that's quite a chunk of it.

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very rough idle.....

very rough idle.....