1)this is not normal......the idle should not surge ......This to me would not be close to acceptable....

2) Yes offer less money .......if you could convince me to buy it???? if you could convince me it was only cosmetic???? Likly a lot less $ .....$1000-2000 or so I might nead an ecu...they are around $2000

 

1)this is not normal......It might need a (new) ecu...they are around $2000

An owner in St-Paul, Mi. reported that his ECU had been changed under warranty in an attempt to solve this problem, but without success.

When we read about the different parts that Toyota has changed for different owners across North America, we are left aware that there has not been one success story.

It must be as frustrating for the experts at Toyota head office to solve this.

 

1. I wouldn't want it anymore considering Toyota head office 'threw in the towel' to fix it.

2. at least $2000 less. Since I wouldn't be able to stand it, it would constantly be in the back of my mind that something is wrong even if it is 'cosmetic'.

montreal, now that the weather has warmed up a bit, how has it been acting?

 

1. I wouldn't want it anymore considering Toyota head office 'threw in the towel' to fix it.

2. at least $2000 less. Since I wouldn't be able to stand it, it would constantly be in the back of my mind that something is wrong even if it is 'cosmetic'.

montreal, now that the weather has warmed up a bit, how has it been acting?

Thanks for your answers.

There were a few days last week when it failed at plus 5 degrees C (41 degrees F) and once when it worked at plus 2 degrees C (36 degrees F).

It seems to be more the factor of sitting for a minimum length of time rather than the current temperature.

Of course there is a temperature at which the problem will disappear completely. I suspect that will happen in the next few weeks.

There is an interesting post on the Corolla forum posted by "rated_w".

http://www.toyotanation.com/forum/t72739.html

Food for thought.

 

Bump,

Please vote in this poll in case you haven't done so already.

Thanks

 

I have posted the combined results from all polls at different forums at the top of the first post in this thread.

It appears that no more than 8% have this issue.

 

Now that both the cold weather and my idle hunting are back, I am bumping the thread.

I have heard of this problem occuring on an ECHO as well.

The MP3 recording referred to in the first post of this thread is again available for auditioning. The recording is now hosted on the GENVIBE forum and requires a link to the post and click on the attachment.

 

Wow.... That sounds like a badly timed lawnmower.....


Have you had this checkout at a dealer?????


Ca pas de bon sens!

 

Wow.... That sounds like a badly timed lawnmower.....


Have you had this checkout at a dealer?????


Ca pas de bon sens!

A lawnmower? yes, but not a badly timed lawnmower, just a lawnmower that is running out of fuel and the mechanical speed governor is constantly pulsing the carburator to keep it from dying.

The dealer has seen it twice and this problem is so complex, that it will take the Toyota software engineers in Japan a long time to come up with a solution for what I believe is a conflict in the engine computer which tries to reconcile pollution control with smooth performance. There are unique situations where the computer must place a higher importance on passing an EPA test then on dealing with what may be a marginal un-metered air leak.

Such an air leak may not be bad enough to warrant throwing a PID but bad enough to require a change in the pollution control strategy, which indirectly causes a pulsing idle.

 

http://www.toyotanation.com/forum/t72739.html

Mista, I spy a cross post. The other one is longer.

BULLMKT

 

http://www.toyotanation.com/forum/t72739.html

Mista, I spy a cross post. The other one is longer.

BULLMKT

The Matrix, Corolla, and Vibe all share the same engine, so it makes sense to raise this issue in the different internal and external forums for owners of these 3 cars.

Now that I have learned that the ECHO with a different engine has this problem as well, I have concluded the the same Toyota software has been recycled.

 

BUMP.

Anyone new having this same problem in 2006?

 

Hey Montreal... funny I looked back here...


My Vibe did something similar about a month or so ago. It lasted 2-3 days then stopped.


When starting my car on a cold cold morning, the idle would go up to about 2000-2500 rpm then drop down fast to 800 or so then back up, back down, back up..... etc


This lasted until then engine was hot...


Weird.. and scary... but it finally stopped....

 

Hey Montreal... funny I looked back here...


My Vibe did something similar about a month or so ago. It lasted 2-3 days then stopped.


When starting my car on a cold cold morning, the idle would go up to about 2000-2500 rpm then drop down fast to 800 or so then back up, back down, back up..... etc


This lasted until then engine was hot...


Weird.. and scary... but it finally stopped....

When normal engines are started when cold, they usually go quickly to 1800 rpm and slowly settle down to 800 over the following 4-5 minutes.

For engines like mine that pulse, they start at 1800 and rise to 2300 during the 1st. minute, then they pulse between 2300 and 1900 (as indicated on the tac). THe pulsing can last up to 1 minute and the number of pulses during that minute will vary according to how cold the engine oil is. The colder the oil, the longer the it takes the motor to rise and fall betewwn the upper and lower rpm limits.

I can't explain what would cause your rpms to drop so far down.

Glad to here your problem went away.

 

As of today, we are 21 owners with this same problem located on 5 different forum boards.

I'm bumping this up to the front page for the benefit of any new Matrix owners who may just be becoming aware that their car has the same issue.

It normally takes a few consecutive days of near freezing weather to get the symptom to come out in cars which have this latent defect.

 

Two answers for you

It could be the Idle Speed control valve, which lets air into the engine when the throttle is completely closed. All it does is take signals from the ECU and operates a small valve to let in just enough air for the engine to idle. Now what your car is doing happens to them when they are not heated. Which is why it has coolant flowing in and out of it so the valve operates properly. However it take a bit for the coolant to warm up, so the valve could be manfunctioning while it is still cold.

Second theory, something that the matrix has that I have not read about any other car having is a valve inside the exhaust. You know how semi trucks have that lid on top of their exhaust that flips up when more exhaust is pushed through it. The matrix's have the exact same thing, but inside the exhaust. This helps maintain backpressure and performance and prevents that burping noise that hondas make when people just have a straight pipe to the engine instead of a cat and muffler.

Now what could be happening is that your exhaust pipe is so cold that it constricts around the valve so much that is doesnt move freely like it should. I don't know where it is located exactly, but it should be somwhere between the cat and the headers.

 

It could be the Idle Speed control valve, which lets air into the engine when the throttle is completely closed. All it does is take signals from the ECU and operates a small valve to let in just enough air for the engine to idle. Now what your car is doing happens to them when they are not heated. Which is why it has coolant flowing in and out of it so the valve operates properly. However it take a bit for the coolant to warm up, so the valve could be manfunctioning while it is still cold.

The main reason I have dismissed this theory is that my car idles perfectly after the ECU fuse is pulled and the factory parameters are reloaded. If the IAC valve was really defective (stuck in a position that creates an intolerably high idle speed) then my engine would always hunt, with or without a computer reset. As well, the ECU monitors the actual idle speed and compares it to what it has requested based on the IAC valve duty cycle. If there is a large discrepency, then the ECU records an error code to flag the IAC controlled idle speed as being too high or too low. To date, I have never gotten such an error code.

Second theory, something that the matrix has that I have not read about any other car having is a valve inside the exhaust. You know how semi trucks have that lid on top of their exhaust that flips up when more exhaust is pushed through it. The matrix's have the exact same thing, but inside the exhaust. This helps maintain backpressure and performance and prevents that burping noise that hondas make when people just have a straight pipe to the engine instead of a cat and muffler.

Now what could be happening is that your exhaust pipe is so cold that it constricts around the valve so much that is doesnt move freely like it should. I don't know where it is located exactly, but it should be somwhere between the cat and the headers.

For the same reason as I mentioned above, I must dismiss this second theory.

What I hope you will appreciate is that a computer reset will allow the engine to work perfectly for 2 days. With each day, the cold idle speed for the following morning is scheduled to be 200 rpms higher. So with each day, the rpms creep up 200 at a time until the dangerous threshold of 2300 is passed. After that, another part of the software, that has no idea that the first part has been scheduling these increases, takes over and institutes an emergency fuel cut. What you hear on the audio recording is the repetitive cyle of fuel cut,fuel restore, idle increasing above threshold, fuel cut, fuel restore.......for 30 to 60 seconds, depending on ambiant temperature.

What all the mechanics who have tackled this issue across North America have come to realize is that the cause is not some easy to identify component sitting on the surface of the engine.

My personal theory is that there is a combination of engine components that are borderline in tolerence and instead of these calibration errors canceling out, as might be the case in a normal engine, these errors, by some freak chance, all compound in the same direction to trick the computer into erroneously thinking that there is a too lean or too rich condition that needs to be corrected.

Imagine that you were walking around the assembly plant and picking out of parts bins different engine components. Each component indirectly affects the fuel/air ratio. Some components cause the ratio to be higher and others cause the ratio to be lower. When all thrown together, the law of averages will nullify these errors. What would be the probability that you could pick out a set of components that ALL raised the ratio? The chances would be pretty low, but it must happen. And when it does, the ECU will find nothing wrong with each component because each is just within spec. I think that the ECU was never designed to accomodate this rare group of sensors and actuators. That's the best answer I can come up with after nearly 2 years of following this story.

I am more interested in having you vote in the poll and post answers to the two questions posed at the end of the first post. This might encourage Toyota to deliver on their promise to look for a solution.

Thanks for your suggestions.

 

Well if your car is still under warranty then I would go in there and demand them to fix your car and give you a loaner until they figure it out. I let them screw me around and now Ive got a catalytic converter that I have to pay for. I would agree with you though, its gotta be a sensor most likely. Sure the ecu does control the idle air control, but the signal it sends to the IACV is created from the signals from some sensor somewhere.

The reason it works for two days and then starts doing it again is because the ecu is always tuning itself. I think they do this for elevation changes. Either way, I would agree, it is some sensor somewhere. I had a friend whos talon did the same thing but thats just because he had the stock fuel pump going through bigger injectors. But hey you never know.

 

Well if your car is still under warranty then I would go in there and demand them to fix your car and give you a loaner until they figure it out. I let them screw me around and now Ive got a catalytic converter that I have to pay for. I would agree with you though, its gotta be a sensor most likely. Sure the ecu does control the idle air control, but the signal it sends to the IACV is created from the signals from some sensor somewhere.

The reason it works for two days and then starts doing it again is because the ecu is always tuning itself. I think they do this for elevation changes. Either way, I would agree, it is some sensor somewhere. I had a friend whos talon did the same thing but thats just because he had the stock fuel pump going through bigger injectors. But hey you never know.

My dealer had my car in twice in one week in their futile attempt to fix it. The Toyota Head office stopped authorizing the warranty work claiming that the car worked, did not polute and got its proper fuel economy. My dealer's service manager refused to believe that my car would not be resellable at the same price as cars without the noise. That is when I started these 5 internet polls which ask the two questions related to public tolerence of this noise and its consequence on resale value.

Your willingness to answer these two questions (see first post) is more valuable than an explanation of the source of the problem. Some of the best mechanics across North America plus their support team at head office can't crack this nut, so this problem will probably end up more a legal one than a technical one.

Thanks and please vote.

 

Well, where I live. It never gets anywhere near freezing temps. But on cold starts my intake sounds like a vacuum cleaner suckin in everything in sight:lol: sorry hehe, but cant help ya. mine appears normal....atleast for now.

 

Well, where I live. It never gets anywhere near freezing temps. But on cold starts my intake sounds like a vacuum cleaner suckin in everything in sight:lol: sorry hehe, but cant help ya. mine appears normal....atleast for now.

Anyone, like you, who lives as far south as Anaheim is never going to hear it. You need a few consequetive days of freezing temperatures to bring it out in cars which have this latent defect.

I imagine the percentage of cars in the south of the U.S. with this problem matches the percentage of cars in the north, but you would never know it unless all those southern cars drove north in winter for a week long vacation.

 

I'll have to vote when in a month or so when it gets cold here. I just bought my 03 XR this year, it'll be my first winter with it.

 

I'll have to vote when in a month or so when it gets cold here. I just bought my 03 XR this year, it'll be my first winter with it.

You should not have to worry about having this problem.

Your chances are about 1 in 1000, which is good news for you, and bad news for my group of 21 who have it. There must have been more than a hundred thousand Matrix, Corolla, and Vibe engines produced in the last 5 yeasr, and while the polls might make give us the impression that 13% of forum members have this problem, there are probably eighty thousand owners who are not members of these forums who don't have this issue and didn't vote to this effect.

Our big challenge is getting Toyota North America to help 0.1% of its clients with a remedy that I believe will not come cheaply.


When the cold weather arrives, leave you car outdoors overnight and get out your stopwatch the next morning so you make sure you let the car idle for at least 2 minutes. This only happens with manual transmissions by the way.

Looking forward to your vote.

 

Well, I have a manual tranny and it gets pretty f///in cold here in WI. I'll let you know when the temp stays under 30 for a week or so.

 

I have a new 2006 XR 4WD (auto) with about 1000 miles on it. I've never heard that sound on my car and it would be extremely objectable for me to own a car that sounds like yours. If your theory about borderline tolerances with the engine components is correct, then it'll only be a matter of time before something wears down to below tolerance (probably after the warranty runs out) and you'll start experiencing major malfunctions. I would not even consider buying a car that doesn't sound right. First of all, there are no guarantees that this issue is purely cosmetic. Secondly, I can find plenty of other second-hand Matrices to choose from. Have you had the car inspected by an independent mechanic?