[neuromystical]

Problem:

When starting car the idle runs rough and then will eventually die. Will die at stop lights. If I press the gas while at a stop I can keep it running by shifting to neutral or going to park.

Err Codes: P0300, P0442

What I have done since(with no resolution):
1. Cleaned Throttle Body
2. Cleaned the Mass Air Intake Sensor(in front of air filter)
3. Replaced Ignition Coil
4. Replaced Spark Plugs
5. Replaced wireset
6. Replaced Ignition Control Module
7. Checked the Fuel line pressure and is registering 58-60psi.

My ideas are

1. The Throttle Position Sensor(TPS) is bad an thus will need to replace the entire throttle body.(Autozone does not have the Throttle Body).
2. Intake Manifold leak/vacuum issue

I am not a mechanic, fast learner, trying to resolve this.

Any help is very appreciated.

 

[Starship]

Welcome to the forum. It sounds like an air leak. How did the spark plugs look? Do you have freeze frame data to go along with P0300? Did this problem suddenly show up? Accident history, current mileage, aftermarket modifications?

 

[neuromystical]

Thank you for you reply!

The spark plugs had a little wear, I will take pictures this evening and post links to those. I went ahead and replaced them though since I was looking.

I do not have "freeze frame data" other than there were vacuum leak or multiple misfires.

The car has 78k. The car was rear ended late last year, but was very small damage and was not high speed.

Yes, it suddenly showed up. This happened about two weeks ago, which the weather got a lot colder too here in Columbus, Ohio. The car is not parked in a garage and thus bares the elements. This is my sister-in-law's car and thus I asked her how if she lets it warm up much when it is cold and a couple minutes if at all is what I am gathering.

If I were to test for a leak, how would I go about doing this? What spray or substance and where to apply it?

Thanks

 

[Starship]

You can use any carburetor or throttle body cleaner spray cans (they come with a thin plastic nozzle). Read a pharagraph or two at http://www.aa1car.com/library/vacleak.htm. Also, ask if she got some gasoline at a service station that's not her usual one. Sometimes all that's needed is a bottle of fuel system cleaner and full tank of fresh gas.

 

[neuromystical]

Got Throttle cleaner! Will check this out this evening.

When this started she had 1/4 tank or less and when and filled up(regular unleaded) and then also put in fuel cleaner of STP. From working on it I filled it up with a higher octane gasoline.

Thank you

 

[neuromystical]

I used throttle body cleaner tonight and sprayed around the intake manifold along with the hose and noticed nothing different. I checked the torque on the spark plugs to verify I had 15lbs torque. I unplugged the mass air intake sensor and started the car and it would run without stalling. When I connected the mass air intake sensor back up it seemed to run better until I took it on a test drive.

Question: Does the 4 cylinder engine even have a PCV valve? If so where is it?

Here are the old spark plugs:

http://dl.dropbox.com/u/9461286/IMAG0161.jpg
http://dl.dropbox.com/u/9461286/IMAG0162.jpg
http://dl.dropbox.com/u/9461286/IMAG0163.jpg

New spark plugs:
http://dl.dropbox.com/u/9461286/IMAG0164.jpg

I took a small video without mass air intake sensor:
http://dl.dropbox.com/u/9461286/VIDEO0004.3gp

With mass air intake sensor:
http://dl.dropbox.com/u/9461286/VIDEO0005.3gp

 

[Starship]

The old spark plugs don't seem to be fouled (no carbon on the insulator, no soaking oil residue), as far as I can see.

There's no PCV valve on the 2.2L, just a PCV hose that goes between the camshaft cover and the intake manifold. See http://cid-54465800aad91b49.office.live.com/self.aspx/pub/Crankcase%20Ventilation%20Hose%20^5L61^6.gif. You can try taking the hose off of the intake manifold nipple and plug it (the nipple, not the hose, of course) to see if the PCV plumbing is the source of the air leak.

If unplugging the MAF sensor made a difference, maybe there's a wiring problem (although usually there should be one or more DTCs with the malfunction indicator). Try feeling for a soft spot along the MAF/IAT sensor wiring with the engine running. If you're lucky, you may hit a spot where the idle problem gets better/worse. You can also check each wire/terminal separately with a multimeter. See the powertrain wiring diagrams:

http://cid-54465800aad91b49.office.live.com/self.aspx/pub/va225095.pdf
http://cid-54465800aad91b49.office.live.com/self.aspx/pub/va225096.pdf
http://cid-54465800aad91b49.office.live.com/self.aspx/pub/va225100.pdf
http://cid-54465800aad91b49.office.live.com/self.aspx/pub/va225101.pdf

BTW, these are for 2005 Malibu with 2.2L, not Malibu Classic.

 

[Starship]

Shoot, something was bothering me and I just realized what it was. The PCV hose you see is the breather side. If you try unplugging the PCV hose, you'll want to plug both the hose and the nipple or you'll create a huge source of air leak.

 

[neuromystical]

Okay, everything seems fine still. I am thinking of going ahead and replace the Mass Air Flow Sensor. However, I went to buy a T20 Security bit however it does not fit. The bit I bought has 6 grooves(hex) and the security screw on the MAF only seems to have 5 grooves. Do you know what tool and size I need in order to take the MAF off and replace?

 

[neuromystical]

Nevermind, finally figured i out.



[ame]http://www.amazon.com/Silverhill-Point-Tamper-Proof-Piece/dp/B002P4YCGM/ref=sr_1_1?ie=UTF8&s=hi&qid=1294804985&sr=1-1[/ame]

 

[Starship]

Are you sure? I guess I dodged a bullet since I've never needed a 5-point star torx tamper proof security bit. And, I've got my share of tools I bought and used once and only once. Anyway, the reason I mentioned the wiring problem was because everything was fine with the MAF/IAT sensor connected and then the problem returned while driving (vibration).

 

[neuromystical]

Okay, so I am waiting on the security bit(I am positive about tool now), only some models of the Malibu have it. Don't ask me why!

So I noticed that if I start the car, it will run okay in PARK albeit the engine still vibrates and such. As soon as I put it in DRIVE then it acts sporadically. Whatever that means I have no clue, but thought it was worth mentioning.

 

[neuromystical]

When I say I put it in DRIVE I mean I have the break on and am just sitting there. Same occurs when test driving and I come to a stop sign or light.

 

[05ls]

I just helped a buddy with his L61 2.2 on his 2005 Cavalier and this could be the same issue (I noticed two of your plugs looked worse than the others):

Very common problem as per the technical service bulletin I sent. Doing some reading, the PCV orifice needs to be cleaned out. Here's a good picture of the dirty orifice and the guy complaining that it plugged up again after 2 weeks:
http://www.ecotecforum.com/forums/showthread.php?14411-2.2-Ecotec-burning-oil-help-with-isolation

Here's a good version of the bulletin with okay pictures. The middle picture with the arrow points to the orifice to clean:
http://www.chevelles.com/forums/showthread.php?t=219091

I'm guess the matching orifice on the head should be cleaned too (small hole between intake ports for cylinder 2 and 3):
http://www.ramscyl.com/images/GM_Ecotec 22.gif

Here's one guy who just opted for a breather instead of tying the valve cover vent tube back to the intake:
http://i92.photobucket.com/albums/l33/rugbyguystu/intake4.jpg

I've heard that guys who do this sometimes can just end up with an oil-bathed engine due to excessive amounts of oil going through the breather. The problem with the breather is that it doesn't fix the root cause of the problem which is the blocked pcv orifice. Leaving the orifice blocked will also foul the spark plugs in cylinders 2 and 3.
http://img155.imageshack.us/img155/1336/1040473.jpg
http://www.gaownersclub.com/forum/showthread.php?t=128116&page=2 (see posting #35)

 

[neuromystical]

Just an update. Finally fixed. It turned out the timing chain had some bad links, the tensioner needed replaced and the guides were all missing. Replaced them and the car is running like new. This is why I was getting misfires. I also got computer reflashed with current version.

I had to go to the dealer on this one as I am not comfortable doing that level of work.

 

[Mrfixit]

05 Malibu with 2.2 4 cyl. low idle. This is not a "fly by wire" system it only has a TPS( throttle position sensor). There is a torx bit screw that is used to adjust the idle, It's a 20 torx bit.Turns very hard. It's , under the cable arm, 1/4 turn will raise RPM about 300 to 400 RPM.