Last winter, I noticed the engine was surging intermittently after start-up, until the engine warmed up. No issues on warmer days, spring/summer, etc… Recently, the check engine light came on, so I took it into the shop. The shop did not feel the problem was the throttle body, and replaced the mass air flow sensor. The engine is still doing the surging thing after starting up. Any ideas what the problem is?
Has anyone checked the idle air control valve (IAC)?
If the check engine light came on then there was an error code stored. Presumably the shop that you took it to retrieved the error code. It looked like “P1234” - what was the exact error code?
The car does that to warm up in cold weather. Nothing wrong.
Intermittent surging with a check engine light means there is something wrong and if you want help here then the code(s) is the place to start.
If the surging occurs while driving the vehicle after the cold start-up, the problem might be with the throttle position sensor.
There are only four primary inputs into the computer when the engine is cold. These are the coolant temp sensor for the computer, the crankshaft position sensor, the MAF/MAP sensor, and the throttle position sensor.
If you provide us with the exact fault code, not the interpretation, we’ll try to help you
Perhaps we can even provide you with some bulletins
The 2005 Vibe does not have an IACV (it’s drive-by-wire).
My first guess would have been a dirty MAF sensor, but that was changed.
My second guess would be an inaccurate temp sensor, but an error code would make for a more educated guess.
If the code is P0171 I would first guess a leaky intake manifold gasket: a common problem on this engine in cold weather.
@circuitsmith, multiple auto parts websites say the 2005 Vibe does in fact have an IACV. Drive-by-wire eliminates the mechanical linkage to the throttle, but it doesn’t eliminate the need for an idle air bypass.
@jesmed, my 2006 Matrix has the same engine and there’s no IACV, the motorized throttle adjusts for idle.
@circuitsmith, if you Google “2005 Pontiac Vibe idlea air control valve” and click on the “shopping” tab, you’ll find that all major auto parts chains have one listed. Same for 2006 model year.
If you do the same search for 2006 Matrix, you’ll get plenty of results for the same IAC valve. Check it out.
Here’s one such result. If you click on the “buyers guide” tab at the bottom it lists applications on the 2003-2006 Vibe and Matrix.
@jesmed, does an OEM Toyota vendor (online dealer) list an IACV?
toyotaonlineparts.com does not.
The aftermarket stores are mistaken.
I could go home and take a photo of under the hood of my Matrix for you, but it’s not worth the trouble.
Interesting…I didn’t know so many aftermarket vendors could all make the same mistake. Sorry for the confusion.
They also list one for my 02 Camry.And between looking on the car and in the factory service manual and I can’t find it.
Buyers guide says:
Make Model Year Engine Type
TOYOTA CAMRY 2001 L4-2.2L Idle Air Control Valve -
TOYOTA CAMRY 03-02 L4-2.4L Idle Air Control Valve -
It may very well fit on the 01 Which had the 5S-FE 2.2l, that had an actual cable operated throttle.
In 02 Toyota went to the 2AZ-FE 2.4l, which is drive by wire and idle is regulated by the ECU and the throttle control motor, completely different from the 5S-FE.
They obviously go by what ever their supplier tells them which, in at least the 02 Camry is pure BS.
I didn't know so many aftermarket vendors could all make the same mistake.Because if you look closely they all probably carry the same after market brand and that's the sales pitch they are fed.
Not just that website, but many others (NAPA, Rock Auto, Autopartswarehouse, etc) have the same erroneous listings for an IACV for the Vibe and Matrix. Go figure.
The Toyota service manual shows for the Matrix only the 1ZZ-FE front wheel drive to have electronic throttle control. The 1ZZ-FE AWD and the 2ZZ-GE have cable operated throttle bodies.
The intake manifold gaskets on the Matrix frequently fail. That may account for your problem.
If the OP has the Vibe GT then he has the 2zz-ge engine, and yes, an IACV.
In 2005 most Vibe/Matrix/Corolla went to DBW.