How do I fix my car having a rough idle after replacing the alternator?
You're right to assume that something else going on. Because it is!Personally I'd check to see if the alternator is providing the right amount of voltage. it's not impossible to get the wrong part installed. and when I say that, I don't necessarily mean you chose the wrong part, but during the assembly line a part they grabbed while assembling the alternator could have been or of spec or something. Check the grounds. A lot of the time, over years of use a little sand blasting or sand papering of the hookups does help. while running the engine, disconnect the battery. A poorly performing battery can drag the entire system down. check to make sure your AC ain't causin' problems too. make sure the clutch is spinning or not spinning when not being used. double check the water pump to see if it was messed up. lastly check all your ignition wiring too. depending on the model year and brand, it might be chatty with obd2. if it's carbureted, obviously you won't get any feedback. if it is obd2, there might be information in there that can give you an idea of what's going on. so get a reader and check. also with modern fi engines, they'll run rough after a battery removal for a while. make sure your fuel economy hasn't been affected, if it has, it's a clear indication that something is wrong.
What are the main causes of high oil pressure?
Oil pressure in a car is measured as the resistance to flow between the oil pump in the oil pan and the bearings in the crankshaft. If it is actually too high, it means you are not getting enough oil through the bearings to keep your engine from self destructing.The higher your rpm, the higher your oil pressure, up to the point where an extra valve detours the excess oil back to the oil pan to recirculate. Typically, at idle you will have 10 to 15 psi, with 30 to 40 psi at driving speeds.The colder your engine, the higher your oil pressure, as the oil is still much thicker than it will be at operating temperatures. Typically, on startup, you will have 40 to 60 psi, which will drop to ranges listed above once the engine heats up.A high oil pressure reading on your gauge means:The oil is too viscous (thick). Most cars today are designed for 0W-20 to 5W-30 viscosity. If you are using 10W-40, 20W-50 or something like that, you will have high oil pressure and high wear.Your filter bypass valve on the filter or in the block is stuck closed, and the oil is too thick or dirty to pass through the filter media, trying to go through the bypass valve.If the high pressure is at high rpm, it may be the secondary bypass valve I mentioned at the beginning.Clogged oil passages to the bearings from sludge.Your thermostat is missing or stuck open, not letting the engine heat up.Your gauge is broken. Check it with a manual gauge.
Does a faulty knock sensor affect engine performance?
Yes, it absolutely can.As someone else mentioned, the majority of failures are due to the lack of a signal. Performance is unaffected if there's no signal. However, OEMs can decide to force a "limp mode" condition to protect the engine which will be a significant and obvious reduction in power.If you have an over-active knock sensor then engine performance will be affected. For most vehicles, the reduction in power is probably going to be small. However, for high-performance engines, especially turbocharged or supercharged motors, the power loss will be more noticeable.If the knock sensor were to consistantly report knock then most modern ECUs react by pulling a large amount of ignition timing (5+ degrees of retard) which can reduce engine output by up to 25%.The ECU will also start to learn knock events. If the knock occurs several times at the same conditions (load) the modern ECU responds by applying a small reduction in timing at that point in the ignition trim table. This means that the engine's performance will degrade over time if the knock sensor continues to report false knock.You can reset the corrections by resetting the ECU. The easiest way to do that is to unplug the battery for a while. The ECU will then use the base ignition values, returning any lost engine power due to the learning. This is important to do when you replace a faulty knock-sensor.Also follow me on … Instagram — Come and Drive It (@comeanddriveit) Facebook — Come and Drive ItTwitter — Come and Drive It
How long can I drive my car with bad coil packs?
It is not a question of how long you can do it. It is more a question if you should.The answer is you should not. You can drive the car until it breaks down completely (and it will). While doing so you will, as pointed out by other answers, run the risk of damaging the converter but you also run the risk of fire.If the coil is faulty very bad things can happen. Car fires are usually related to causes associated with fuel, and/or electrical. Once a fuel part starts leaking while a car is running, a fuel drip can be the formula for fire if you get sparks from a spark plug wire or an ignition coil that is faulty. Something like this could be the end result. (the image is from the web, I am just using it to illustrate a possible scenario, I do not know what happened with the beamer) But I have seen a Lancia catch fire from a faulty ignition coil.So, why risk it? Yes, they are not cheap, but you really should get a new one. By trying to "save" a few bucks you may end up having to spend a lot more.
Why is my car shaking and the check engine light flashing?
A shaking vehicle AND flashing MIL ("check engine light") sound like the vehicle is misfiring on at least one cylinder. As @Anna Nguyen, @Brendan Sinclair, @Antoun Nabhan and others have said, it could be an ignition related problem. It could also be fuel-related. If one or more fuel injectors are clogged or dead, that would also cause a misfire in the affected cylinder(s). These are relatively cheap/easy things to check and fix.Other causes (which could be more complicated and more expensive) to fix include contaminated fuel, a bent intake or exhaust valve, a broken valve spring, a damaged piston/connecting rod, and on and on.I recommend getting a scan tool and checking the codes which are causing the MIL to light/flash and I also strongly recommend NOT driving the vehicle until the problem is fixed. If you continue to drive the vehicle as is, you will exacerbate the problem. Dumping unburned fuel into the exhaust due to a misfire will overheat and kill your catalytic converter. A more serious problem like a bent valve can eventually cause you to crater your engine (i.e.: completely destroy the engine).
What will happen if I drive with a very low transmission fluid?
It depends on whether your car is an automatic or manual transmission.Automatic: Automatic transmission fluid has multiple jobs in an automatic transmission. First, it is used for cooling the transmission. So, with low transmission fluid, your transmission will not be cooled properly. Second, it used to make the torque converter operate, and provide pressure to ensure proper operation of the various clutches and components within the transmission. Third, it is used to lubricate your transmission. If your transmission fluid is very low, the transmission will almost certainly be slipping. So it will feel like the vehicle is in neutral, with the engine revving, but no power being applied to the wheels. The shifts will be rough, if they occur at all, as the clutches are not getting proper pressure to perform shifts smoothly. If the transmission fluid is very low for a long period of time, the clutches will burn up from not being able to lock up properly, and the torque converter will likely fail due to improper fluid pressure. If you drive your automatic transmission vehicle with low transmission fluid, at some point, you will be looking at a bare minimum $2,000+ repair bill unless you are able to do the work yourself, in which case it will still be $1,000 plus.Manual: In a manual transmission, low transmission fluid will cause the gears, synchronizers, shift forks, and other components to wear quickly. The bearings within the transmission will also not be lubricated properly, and the transmission will begin to overheat. It will likely be quite difficult to shift the transmission between gears, if not impossible. A manual transmission with low fluid may last longer than an automatic transmission with low fluid, but the prognosis is still the same. Transmission failure will occur, at some point, sooner or later.If your transmission fluid is low, it is much cheaper and safer to fill it, rather than face the expensive repair bill. Fill the transmission fluid and keep an eye on your vehicle, as it is likely that you have a leak, especially if your transmission fluid is frequently low.
Can a faulty speed sensor cause other problems in your vehicle?
Speed sensor is only for speedometer in old car's .The ECT electronic controlled transmission is integrated with VSC vehicle speed sensor ……sp 1 and sp 2. Malfunction of speed sensor can trigger engine check light ,vsc light ,abnormal gear change.If engaged in high gears can burn clutch linings.The trouble indicating codes can be p0500.