Engine surges when very cold

[Heh! heh!]

This winter, besides having to get boosted twice, on several very cold occasions, the engine repeated began surging then falling back when the clutch was engaged or when the car was idling in neutral. It was a bit unnerving. The dealer, of course found nothing wrong. Weird.

[joatmon]

welcome back I know that you can get some idle speed increase when various things cycle on and off, the AC compressor, the engine fan, etc. You can make the RPMs go up when just sitting there by turning the steering wheel. How high does it surge, and is it one surge, or do the RPMs cycle up and down while you sit there in neutral ?The battery in the cold is discussed at great length in http://forums.genvibe.com/zerothread?id=2976

[JohnC]

I have owned several cars that would do this. It is kinda embarasing because the engine races when you engage the clutch, everyone thinks your just a spas that doesn't know how to shift. Well it turned out to be the throttlebody was dirty. Cured the problem by spraying intake cleaner into the throttlebody (per directions on the can). I would do this just prior to changing my oil incase it happened to get past the rings and into the crankcase. Just a thought.

[Heh! heh!]

Basically, it surges and drops, over and over, until the car is somewhat warmed up, a couple of minutes at most, but only when it was very cold.

[Heh! heh!]

This doesn't sound normal at all. Sounds like something taken possession of it, like the stuck choke on my old Ford fairmont, but this sounds like it's stuck opening and closing.

[AKLGT]

mine does the same in colder temps. i'm used to it by now so it doesn't really bother me unless it idles so low at a stop light that it dies. now that sucks! i've killed it a few times and once not that long ago, like 2 wks ago at a light! i almost have to gas the sucker to bring the rpms high enough that when i release the clutch it doesn just go sputter... and die.

[Stang2Vibe]

I get the same thing in the cold. My engine doesn't really surge, but if I don't give it a little extra gas when starting out, it will stall. Sometimes a lot of extra gas. Yes, that is very annoying but it is the price we pay for having an engine with rather little torque.

[montreal]

I have a Toyota Matrix and have started a thread similar to this one on the MATRIXOWNERS.COM site. Matrix and Vibe share the same motor and thus have similar problems. After 3 years of living with this problem and after watching the forum thread grow to 4 pages, I finally took my car in and today it appears that the problem has been solved by changing the front Oxygen sensor. My guess is that the sensor's heater circuit was not intact and the sensor never pre-heated. This would explain how the ECU proposed a bad fuel/air mixture that caused the hunting during the second minute following startup on a cold day. Once the sensor reached operating temperature due to the hot exhaust gases, it worked fine and never caused the check engine light to come on. There may be other reasons why you get the same problem even if your oxygen sensor is OK. It is possible that poorly functioning temperature sensors or air flow sensor could confuse the computer. Or, if one or more of the injectors is delivering the wrong quantity of fuel when cold, or the stepper motor that opens the idle air bypass valve is marginal, then that will cause the same symptoms.Check out the other site:http://www.matrixowners.com/fo...art=0

[montreal]

Not so fast. This morning with the outdoor temperture at 20 degrees F., the engine idle failed in the same traditional way. Is the newly replaced front O2 sensor not supplying information because the original problem was not the sensor itself but a flaw in the electrical cabling/connectors? Did the mechanic upon seeing that the original O2 sensor voltage was low wrongly conclude that such a reading when taken one minute after starting the car was abnormal? Or does the real cause of the problem have nothing to do with the O2 sensor and is located in one of the other sensors or actuators or ECU computer? Stay tuned for the continuing saga.

[joatmon]

Interesting, I forgot about this thread. When it was started last spring, my car didn't have this problem, but it has done it this winter. I'm well past warranty so I'll live with it. What does a front oxygen sensor cost?

[montreal]

O2 sensors are between 60$ and 100$. But it may not necesssarily be an O2 sensor problem.Stay tuned.

[montreal]

The following is what will probably be my final posting in this threadand a similar one at a forum devoted to the sister car Toyota Matrix which shares the same engine and same problems as the Pontiac Vibe.This duplicated comment concludes 4 pages of postings at the MatrixOwners.Com forum where many participants encouraged me on in what for them had already been a frustrating dead-end battle to get this issue resolved. So it turned out to be the case for me, as you shall now read....My car was entrusted to the dealer overnight 2 days ago. It had failed every cold winter morning for the last 3 years. It had failed during my first visit to the dealership last week when I first demoed the problem. It failed the following day at the dealership when the mechanic hooked up his scope to the engine. It failed every morning following the changing of the O2 sensor. It failed this morning. But did it fail yesterday morning while the mechanic had the car available for the second time in 2 weeks? NO, according to the mechanic. And as a result, Toyota Canada head office decided that after paying for nearly 5 hours of mechanics time and the cost of a O2 sensor, it no longer wanted to fund any further investigation into the cause of the problem. My dealer added that since the car was drivable, was not wasting gas, and did not appear to be polluting, then Toyota had no choice but to push my dossier down a couple of notches in priority. I asked if my resale value of this car was compromised by having a car that sounds like a donkey braying whenever started after sitting overnight in below freezing temperatures. His answer was many people buy cars such as Chrysler mini vans with a known track record of weak transmissions. Therefore people should be at ease with an un-aesthetic situation that only last 30 seconds should the car not be placed in gear until the 3rd minute following start-up. I am thinking of taking this car (at my expense) to a Pontiac Vibe dealership to see if they have better luck with the same engine.

[montreal]

I have a new theory that this could be a problem which does not affect cars with automatic transmissions, because automatics never spin in neutral as freely as manual transmissions. A difference of 100 - 200 rpms lower may be all that is needed to keep the engine computer happy. Anyone with an automatic experience idle hunting? And if so, does your engine startup at 2000 rpms at first or at 1800? Some manual transmissions also idle 200 rpms lower than mine. Could that be due to the bearing surfaces being looser when cold and allowing some engines to spin higher?

[ArcsVibe]

Just curious to ask which Toyota dealer did you go to?It is not the first time I hear about Toyota dealers leaving clients hi and dry regarding a problem

[montreal]

My dealer is located near the Fairview shopping mall.In all fairness, the dealer offered to continue investigation if I ws willing to pay the shop rate. He said it was Toyota head office that no longer wanted to fund the work under warranty because it considered the car to already be roadworthy, and even if the idle hunting (surging) was an unpleasant sound, it was only for a brief time and no worse than any other rattle that can occur.

[montreal]

In the face of new evidence I am scrapping both of my theories that something is defective with my Idle Speed Control valve.If I disconnect this valve and start the car, the valve in its default position will provide 1200 rpms whether the engine is hot or cold.At the same time the Check Engine Light (CEL) comes on and the factory default settings are re-established. The new cold idle rpm ceiling moves down from 2300 to 1800. There is no longer any hunting. This new ceiling will remain in force for the two trips that are necessary for the CEL light to be automatically cleared by the ECU. After that, the ECU begins raising the cold idle ceiling by 200 rpms for each new trip. Within 3 trips the new ceiling is 2300 without hunting and on the next trip, the idle is at 2300 with hunting.Conclusion (as of today):1) The idle rpm ceiling has been going up because the ECU believes according to a mysterious sensor that my engine has aged and needs a higher idle rpm to warmup more efficiently while keeping pollution at a minimum. This conclusion is based on long term monitoring (3 trips following reset) of this sensor(s) by the ECU.2) Whenever the ECU wants the idle rpm to be higher than the Idle Speed Control valve can provide, in face of this error, the ECU decides to kill the fuel in a repetative manner until a new strategy can be put in place 40 seconds later.

[montreal]

After 2 months of searching in vain, I have arrived at a conclusion about the source of this problem.By my pulling the ECU fuse and resetting the ECU memory, I was able to get my car to function for 2 days without the idle hunting. Erasing the memory causes the ECU to use factory default parameters. It will set the startup cold idle at 1800 rpms, like all cars with the 1zz engine (Toyotas and Vibes).The ECU is designed to learn from each trip and apply this learning to the parameters that it will use during the next trip.What my ECU appears to be learning is that there is no single sensor that is working poorly enough to trigger a CEL light. But my ECU is still not satisfied with the performance (read : pollution) of my engine and does one of two things:1)it orders my startup idle to be 200 rpms higher for the next trip in order to reduce the length of time that my car spends polluting while cold, or2)it orders changes to the fuel trim and timing parameters as a precautionary measure to reduce pollution during startup, which has the unintentional side effect of increasing the cold idle rpms.In either case, I believe that the ECU has a specific over-rev speed for a given temperature and fuel injection volume at which point it does what most ECUs do, cuts and resumes the fuel.Once the fuel is resumed, the rpms rise as before to the threshold and the fuel is cut once again.This pattern repeats until the block temperature rises enough for the ECU to scroll up one position higher in the cold start fuel map table.This is the best explanation I can come up with and it is unlikely that this problem can ever be solved without taking all the sensors off a car that works properly and putting them all on my car.

[joatmon]

thanks for keeping us posted on your detective work. I wish I had a scan tool to hook up and see waht the ECU is thinking, or at least what it is sensing. Mine has done this some this winter, but I have been parking in a garage at night lately, and I guess it doesn't get cold enough to hit the error mode, and I'm hoping that spring comes soon. Usually there are some Vibe experts at the Michigan mega meets, maybe we can get someone at this year's meet to raise the issue and see if they have any idea what's causing it.

[lm7212]

Replace your intake manifold gasket, clean your MAP sensor, and clean the throttle body with regular carb cleaner, inspect and replace throttle body gasket if needed. Night and day difference. Your car is sucking too much raw air from a dried out or improperly factory installed IM gasket, known problem on these 1.8 motors. Parts are $12, work takes less than an hour. If I’m wrong you’re not out much and ready for another 100k miles.