These impalas (2000-2005), at least the 3.4L v6's, have problems with the idle air control value(attached to the back of the throttle body, its(for me) it was a little plastic sensor held on by two bolts, with a simple mechanism inside that allowed it to turn when the throttle moved) getting corroded/dirty and the it doesn't work well. When this happens it causes the car to stall either while parked or driving. In my case, the car stalled while usually after I used my turn signals(strange but I guess they effect the idle of the vehicle when you turn it on) To fix this clean the part with some electronic parts cleaner(found at any auto parts store). DO NOT TAKE IT TO THE DEALER unless you're sure its something that can't be fixed at home. Also the no start issue(no turn over, no crank, security light, passlock...etc) for me, was fixed by taking out the ignition and cleaning the inside with an $8 can or electronics cleaner. After I did that I never had the issue again. I'm not guaranteeing that it will work for you, but here is info on how I fixed it. http://www.naioa.com/v2/modules.php?name=Forums&file=viewtopic&t=33970

Things to do when you buy an impala(from my personal experience):

-Flush out dexcool coolant and refill with a green coolant as soon as possible. This is the best way to prevent a leaking upper or lower intake manifold gasket. You'll know when you have this problem: your car will overheat and the mechanic will find either coolant in the oil or oil in the coolant. Though its debated, dexcool is known to destroy the gaskets in these cars--why take the risk?

-keep transmission fluid changed. I would recommend a synthetic like Castrol. The solenoids in these transmissions are known go out and lead to internal damage. I would think that regular service with a quality trans fluid can help prevent this, since some impalas last longer than others...

Clean sensors(as noted above) should you experience stalling, and get the ignition cylinder replaced under warranty at the dealer(or do it yourself) should you experience the no start issue. Don't let the car leave you in the cold for 10 mins until it finally starts. Sometimes wiggling the key can help(worked for me until I fixed it). There is also passlock bypass instructions somewhere online that can fix the issue. Google it...

Take car of it! It's not a beater Honda or a race car! Don't complain about your tranny going out if you drive it hard. It simply wasn't designed for that. Besides, stock trannies on impalas aren't the best quality. Consider this: http://www.tripleedgeperformance.com/ for Impalas and Monte Carlos.

Join www.NAIOA.COM its an Impala community, and the experts on there can help you with any questions you have.

This isn't a complaint. Impala is a nice car. The design, for its time, made Honda's and Toyota's look like--well...toys. I hope my experiences with this car are useful.

I have been reading that this happens to alot of people, yet there seems to be no fix! I will be driving dwn the highway at misc. speeds and the car decides to cut all power! & die instantly. I have been doing 60 miles an hour and lost all power with my 2 year old baby in the car. Sometimes you can throw it in neutral and restart it and sometimes it won't start at all and I have to pull across 5 lanes of highway to the side to stop it and wait...this is ridiculously dangerous! I have had it in and out of the shop about 6 times over the last year, and about $900.00 later there is NO HOPE!!! What the heck?!? Does ANYONE have freakin clue?

I had my car a little over a month when it started stalling. The first time I was on the way to work and the car was running great. All of a sudden, it acted like it was in neutral although it was in drive and I was still pressing the gas. The RPM was increasing, and the speed decreasing. Then it caught...it kinda jerked and started running fine again. About 10 miles down the road, it shut off while I was driving. It started again after 4 tries. It didn't do it again until a few weeks later when I was pulling out my driveway. I slowly pressed the gas to pull out, my car started moving forward. I was crossing traffic to get out of the driveway and once in the middle of the road, the car decided to stall...and there was a car coming! I thought "Oh, sh*t!" but it caught and jolted me to my side of the road.

The car tends to do this very often now. Occasionally it will cut off while driving an not crank back for about 1-7 hours. Yeah, I've had to leave my car on the side of the road a few times and come back for it the next day when it will work fine. I took it to the shop, and they hooked it to a computer to see if they could find problem. Of course, everything was showing great! I ended up troubleshooting it myself; we bought a fuel filter, fuel pump, crankshaft sensor, mass air flow sensor, and some other bull. Overall, I spent around $2500 and the problem still isn't fixed!!

This problem of stalling at random actually began in the summer of 2006. It would happen waiting at stop lights, and even driving at freeway speeds. I really do not think there is a fix for this stupid problem and Chevrolet is too cheap to do anything about it. I knew that when I was car shopping I should have bought a foreign car, like a Honda or Toyota, because American cars SUCK. I had my car diagnosed to see what the problem was and they said it was a bad crankshaft sensor. I did not replace it at the time because the weather started to get colder and the problem was not becoming a problem anymore. So the next summer it happened a few times but not as much as the summer of 2006. I had a few things fixed in my car so I could get it registered in the state I live in, mentioning to the repair shop the diagnostics that had been done about a year previous. They kind of nodded their heads but when I got the receipt of what they fixed there was nothing on the receipt mentioning the crankshaft sensor and they assured me that the car would not stall on me anymore. So much for Chevy!!

My 2000 Impala would cut off, intermittently, usually when I was first in line at a red light, as soon as that red light turned green. I can't remember exact dates and mileage, but I did have a code P0336, crankshaft sensor fault. Once, the car actually SHUT DOWN when I was driving 45mph. So I finally replaced the sensor.

Approx 2 years later my wife was driving my 5 month old to the sitter's and the car dies on her. This time, it wouldn't restart. So she sat in a left turn lane, wanting to go straight, during morning rush hour, broke down. Long story short, she finally got to the sitter's (car did finally start up) but she used their car do drive to work because she was too scared to drive our P.O.S. I checked out the car when I got home. I got the same fault code so I replaced the crank sensor again.

That was about 3 or 4 months ago, and the car is still acting stupid. It shuts off when idling at a light. It hesitates when driving, you can feel it "buck" every once in a while. This time, I don't get any fault code. A friend recommended a new fuel pump. $266 later, it still has the same problem. I even swapped the fuel pump relay with the DRL relay as they are identical. No fix.

I replaced one of the coil packs a few years ago due to a rusted terminal. That had no effect. But it was recommended to replace the coil by someone who "had the same symptoms on his car."

The car has become a mission to fix. I am thinking about replacing the remaining two coils and the ignition module. I've learned that a faulty sensor WILL NOT cause the engine to shut off. At least it's not supposed to. If the crank sensor fails to give input to the PCM, the PCM will continue to run the engine with the cam sensor input.

Any help would be appreciated.

Chevy has not won any points with me after buying the 2000 Impala LS (NEW). The car has been a "lemon" since day one. Not only that - but all of the problems with the car can be found reported time and again on these message boards. About a year ago, I had the fun issue of the car not starting and when it did start, it would eventually stall at lights and sometimes while driving. Dear hubby replaced the crank shaft sensor and Chevy happily replaced the Pass Lock System (for about 500 bucks). The car ran ok after that but still "pulsed" on the road, causing me to have to let my foot off of the gas and reapply. In general, the car has never been a great ride despite the great comfort and style. The stalling problem appeared again this week. The car died a few times and started right up again early in the week. This morning, on the way to daycare with my 3-month old in the car, the car died and would not restart (GREAT during rush hour!) After about 5 minutes, the car started and I got around the next corner before it died again. The car restarted and died immediately after. Again, after letting the car sit for about 5 minutes, it started and I made it to daycare. Dear hubby took the car and hooked it up to the meter. Good ol' code p0336 came up again. WHAT? How many times does a crank shaft sensor need to be replaced. And when will Chevy take responsibility for putting out such a piece of crap car.

About a month ago I had to do some errands. When I went to start my car it was really rough and sounded very quiet like it had low RPM (no tach) but I'm not totally sure. Ran fine for a few days and then a friend of mine borrowed the car for a few errands and he calls me from the gas station saying my car won't start. I head over and the engine will crank, but it dies right away. If I give it gas it will run but dies when it comes to an idle. I finally got it to work, and when I used it later in the day it was fine. The problem only happened on startup from operating tempurate. Looked on here and thought CKP sensor was the problem since that sensor was somewhat temperature sensitive since it has to be warm to calibrate it. So I had that replaced at the mechanic since I don't have a scan tool to calibrate it. I got back and let the car sit for a few minutes from operating temperature and tried to start it and no problems. When a week, redid struts and brakes, halfshaft and trying to start the car cold Monday Morning wouldn't start. Got home that night and looked at the dealer manual I have on my comp and started going through everything. Checked the map sensor and it was clean. Then I check the IAC (Idle air control valve) and it was very gunky. I cleaned it out and haven't had a problem since (3 weeks). I am going to replace it though because this is a sensitive device and is really not supposed to be cleaned. My car is a former squad, so they idle for hours a day, so the device goes early on those models. Seach for IAC in yahoo and you'll find former Crown Vic Interceptors had the same problem, and Jeep Cherokees have a recall for this device that sites the sames symptoms that we have all been having. The IAC valve it right on the throttle body under the fuel injector sight shield (3800 Series Cover), and all you need to replace it is a torque set screwdriver. Can get from autoparts stores for about $35. If you open up to see the IAC is dirty, this is most likey your problem. It wouldn't hurt to use throttle body cleaner on the whole throttle body MINUS the IAC. DO NOT ATTEMPT TO USE ANY CLEANERS ON THE IAC. It is a sensitive device and should just be replaced. Like I said, I wiped the gunk off of mine but am replacing the unit.

Had the same problem as some of you have with your Impala stalling while driving. Only difference is that, my car would stall up to 3-4 times per day most of the time and as time went on it got worse. The last time it happened was when my wife was driving to work the car stalled a few yards away from a railroad crossing (since she quit driving on expressway), luckily it didn't happen on tracks, no train was coming at that time. She had to wait approx. 25 mins for it to start after trying a few times. The next day the same thing happens but this time it didn't turn on, so she called the dealership and they sent a tow truck. The tow truck driver, when he arrived approx. an hour later, tried to start it but it didn't start either. So, when arrived at the dealership they tried starting it and by then it started. The shop manager, whom I had related this incident to was aware of the situation, so he then assigned a mech to stand by the analyzer monitor while the engine was running. They kept the engine running until it finally died on them again, while the mech was still there, I don't know how long (didn't ask). At this particular time the analyzer indicated that the Crankshaft Position Sensor was the cause of the stall. After further check-up it was found it had a crack on casing (as in earlier model cars that have a distributor cap and won't start if the cap has a hairline crack on it, same effect here). Needless to say it was replaced and is now a month later and it's running just fine. Not a hint of stalling nor anything else. The only thing I would suggest, if I may, is to take your Impala to your favorite auto shop and have them install the analyzer while the engine is running and have someone standby and keep an eye on the analyzer and wait till it stalls, because, as I was told, it does not show a code. AL

I have had the EXACT same problem with my car. Started in June of 2006. Replaced a few things, did a tune-up. Never could tell if it helped or not because in the beginning it happened maybe once a week. I had a large amount of things replaced in April of 07 because the problem had gotten serious every day, at least once it stalled sometimes it would take me 20 minutes to get out of the driveway. Very stressful. One of the things we replaced was the crankshaft position sensor. I took the car on a road trip (9hrs one way) and back with no problem at all. Didn't happen again.... for a few months in July 07 it started again and was even worse stalling on the highway even, sometimes it would turn off and back on in a second on its own while driving. Had the ignition switch replaced, no fix, had the crankshaft position sensor replaced again... so far (2 months) so good. I wonder if something is causing that sensor to go bad. However now the car is still a piece of crap, with other problems having just popped up. UGH!