What are some symptoms of a bad idle air control sensor?
Idle air control valves open to allow more air to "leak" into the intake, raising the engine rpms, or close when not needed. When your AC compressor kicks in or power steering is activated as you suddenly turn the steering wheel, the sudden drag on the drive belt will bog down the engine. These systems send a signal to the engine computer telling it they are active and it then signals the IAC valve to open, which increases the engine speed. Without this occurring, the engine could struggle, or die. The IAC valve can cause weird idle issues, mess with throttle functionality or cause the car to die. Sometimes they fail, get stuck or just get all carboned up. Sometimes people have success at cleaning them, but generally it is best to replace them when bad. Idle issues and even problems with the IAC valve may not be due to the IAC valve being bad itself. An idle issue does not mean the IAC valve is bad. It is best to pay close attention to how the vehicle is acting, and then communicate that clearly and as completely as possible to your mechanic. Intermittent problems can be very hard to diagnose. Details will help. Knowing more about the vehicle in question and its symptoms (in detail) will also help in understanding more about what it is doing.
Idle Air Control Valve bolt head broke off! Pease help!?
Hi! I have 94 3000gt SL and need my car back before monday for school. I was cleaning the idle air control valve and when i was tightning the bolts that holds the valve in place but one of the bolts broke. Basically the head part broke off and only other bolt is holding the idle air control valve. Now i have a leak thru it and car turns on and shuts off. I took it to mitsubishi service and they are charging $150 labors per hr for 2 hrs and parts etc coming up to $1k. If i can just take out the other half of the broken bolt then im good to go. Can you please help me? how can i take that out? Is there any tools or any other way to hold the idle air control valve? I hate these dealer services! they are trying to rip me off!, specially when im broke and having hard time paying school! Thank you! O
1984 Volvo 240 DL Wagon Rough / Erratic Idle and Stalling Help?
I'm having a sudden issue with my '84 240 DL Wagon (215,000 miles). I purchased it 2 months ago and it's been running wonderfully. Yesterday afternoon, out of the blue, it had trouble kicking over. Once it did, the idle was erratic and shook the car. I was able to rev it--and while revved, it felt and sounded normal. However, if I try to move the car at all in a low gear, or at idle, it stalls out. There were no abnormal "symptoms" leading up to this--the car was running very well. We did hit a pretty deep pothole a few days before the problem surfaced. I've checked everything I could think of (even added gas in case the gas gauge had broken) and I'm stuck. Obviously I didn't check the right thing. Any help would be sincerely appreciated.
Will driving with a oil leak in the valve cover gasket hurt the engine? If so, how can this be prevented?
Is it an oil leak or an oil seep? Does oil run down the side of the engine leaving a clean trail as oil drips on the ground? Or does it just form a nasty, mucky oil-dirt combination that slowly builds?If it's actually a leak, get it fixed now. You can lose sufficient oil to starve the engine and cause premature wear or even failure. On top of that, you have an oil slick being left wherever you go, oil is probably dripping on the exhaust causing nasty fumes (not to mention a potential fire hazard) and you are having to spend money on oil that is just going to hit the ground. Not to mention it's not exactly good for those plants by your driveway to have oil washing into them.If it's a seep, don't ignore it. Get it fixed. If you have to wait a week or 2 for financial reasons, that's understandable, but don't push it out too far as it can develop into a leak. In addition, the dirt, cottonwood fluff, dandelion seeds, etc that can get stuck in the slime will do a few detrimental things. For one, it insulates your engine raising operating temperature a bit. Most cars engine oil relies on the side of the block and the oil pan to radiate heat away. Remember, oil functions as a lubricant, cleaner, and coolant! If the block and pan are caked over in grime, it is harder for the oil to transfer it's heat through the pan and into the air. This grime can also pose a serious fire hazard. Not fun.
Can I drive my car with a broken thermostat?
Yes of course you can! And, you may be surprised by just how far you manage to go, before the engine overheats, seizes, and turns into an immovable, useless, expensive to replace, chunk of metal!It’s probably easier to remove the plates, pour gas all over the inside, and light a match—the effect is about the same. Thermostats invariably fail in the “closed” position so the “shelf life” of a car with a bad thermostat is measured in minutes.You need to borrow a car and go buy another thermostat and gasket—-or at least the gasket. Typically, the cover is held on with two bolts, so use a wrench (or pay a mechanic) to remove the bolts, and then the old thermostat. If you haven’t been able to afford a NEW thermostat, use the new gasket to re-install the cover, and don’t drive too far, especially in winter, til you actually get a new thermostat.
Can a broken radiator cap be the cause of the car overheating..?
The radiator cap has a psi rating on it. It is designed to be air tight and allow a pressure build up in the radiator. Thats why you don't remove a radiator cap when the car is hot, because the hot steam/fluid will shoot out. Kind of like opening a shooken up 2 liter bottle of soda. With that said, I'm not sure if that can actually cause the car to overheat or not, but could. Guess you won't know until you break down and spend the 7.00 to replace it. The other likely thing to cause the car to overheat is a bad thermostat. If you follow the upper radiator hose to where it goes into the engine block (at top of car) then thats where the thermostat is. The hose ends into a metal housing thats screwed on with 2 bolts onto the block. The thermostat is revealed when you take the 2 bolts off. Here is a way to test for a bad thermostat (this isn't the official way to do it, but has always worked for me). Once the car is at operating temperature, grab and slightly squeeze the upper radiator hose. It should be hot to the touch. You should not be able to squeeze/hold it for more than 2 seconds. Also while you are holding it, you should be able to hear/feel the water running through it. If the hose it not hot and is very comfortable for you to hold on to it, then that means the thermostat is stuck close and not allowing water to circulate (thus not passing through the radiator, thus not cooling). If thats the case, then replace it. It's fairly simple. Take the two bolts off and the thermostat will be able to just simply lifted out. Make sure you get a tube of ATV sealant (ask auto store clerk) to put a thin layer of sealant on the gasket before you screw the two bolts, on the housing cover, back on.
Car overheating, heater blowing cold air. Coolant is full. What could be wrong?
Water pump is definitely suspect, but you can verify by removing a hose and seeing if it is pumping right. Temporarily add a piece of cheap plastic pipe to the hose, in order to get it high enough so that water does not run out from gravity. Then with the other end where the hose used to attach plugged, run a water hose in to keep the radiator filled. This should allow you to run the engine log enough to determine if the pump is actually pumping, or if the impeller broke. Although replacing the pump and thermostat is not that expensive, and might just be worth doing, even if they are not really bad, just in case. Finally, is the waterpump driven by timing belt, V-belt, or serpentine? If possible, I would take the belt off and try turning by hand, make sure nothing else driven by the belt is frozen, and if the belt is loose or oily. Make sure the pump is actually turning at sufficient speed. Last suggestion is that I have sometimes seen the suction hose get so soft from age, that it collapses. This will also cause the symptoms you have.
Why does my car idle at a really low RPM while stopped, and start shaking?
You may have a misfire, a vacuum leak, or a clogged/faulty idle air control valve. It could be a couple other things, too, but those are the most common and first things you should explore. This is because:If you have a misfire, one of your cylinders is not working and while that may be less noticeable at higher speeds when the engine is spinning really fast and the throttle is wide open, at lower speeds the difference is more apparent.If there is no misfire (and no codes / check engine light), the problem is most likely air related. This could mean a vacuum leak from a hose or the intake manifold itself. Or, commonly, it could be that your Idle Air Control Valve is clogged or not working well. The engine monitors via sensors how much air is coming in vs engine speed and uses that to control fuel injection and ignition timing.If it's a vacuum leak, the engine is getting more air than it thinks it is and that is causing a 'lean' fuel/air ratio.If the IAC valve (and its passages around the throttle plate) are clogged up, the engine thinks it's getting more air than it really is at idle with the throttle plate closed (foot off the gas), resulting in a 'rich' fuel/air ratio.All of these scenarios will probably cause some sort of engine code and checking them should be your first step. Note that an oxygen sensor code will be indicitave of one of the above 'air' situations because it detects how rich or lean the ratio is.
Motorcycle wont idle?
I have a 1982 Yamaha SR 250 Exciter (single cylinder) and it will not idle. I've taken apart the carburetor, soaked it, blew it out with air, replaced the idle jet and adjusted the air fuel mixture to manufactures specs (all the way down then 3 turns out). I tried various air/fuel mixtures with no success. I ran the bike at a steady idle (by holding throttle) and put a propane all around the intake and there was no spike in the RPM. I even have a spare carburetor from the same bike (one year older but same model) and the bike acts exactly the same. I striped the carburetor fully when I re-built it. The carburetor is controlled by opening the butterfly valve as apposed to the style of carburetor that controls the needle in the main jet. I've had the bike idling before but once you drive it around the block it will do one of two thing, it will idle at 3000+RPM or it will not maintain an idle and stall. Please Help! I'm tempted to take a hammer to the carburetor soon! Kidding, but I'm frustrated to say the least! Matt