What if you have replaced the knock sensor and the engine light still comes on?
The first thing you should do is clear the DTCs (commonly known as “codes”) using an OBDII scan tool. You may also want to reset the ECU’s adaptive learning memory to give it a blank slate to work from since it’s likely learned overly conservative spark advance and fuel supply maps due to the faulty sensor, but this depends on the exact vehicle in question and may be done at the same time as clearing the codes.Next, drive the vehicle normally for several days while monitoring its diagnostics system - at a minimum, wait till the light either comes back on or doesn’t (after several drive cycles), ideally you should be using something like the Torque Pro app and an ELM327 bluetooth OBDII scantool compatible with your phone to watch the live diagnostic data, or even better, an actual professional scantool such as a Snapon Verus, though those are well out of the price range most people will want to spend.If the light comes back on or you see pending DTCs pop up on your scan tool, you still have things to repair. If you make it a while (several drive cycles at least) without it coming back the problem is probably fixed.The reason the light is still on (or came on again after it was reset? You weren’t too clear on that) is because either a problem is still present, or the ECU simply hasn’t had enough time to determine that the problem has gone away yet. Most DTCs will persist for several drive cycles before the ECU clears them itself, and clearing them before performing the drive cycles is usually better from a diagnostics standpoint as you know when they show back up again rather than only noticing a while after the issue was actually repaired because the light finally went out days later.
What would happen if you didn't change a bad mass airflow sensor on your vehicle?
If it is faulty and you do not replace it, the computer will keep sending you a malfunction code and light the “Check Engine” light. At the same time, the computer will default to its preprogramed air/fuel mixture tables to manage fuel flow to the engine.In the end, you will lose engine performance and fuel mileage will suffer significantly because it will it allow more fuel to the engine for a given engine RPM.The reason is that the computer programming is pretty conservative in order to prevent any engine damage that would be caused by an excessively lean fuel condition.Some newer vehicles will most likely revert to limp mode.
What problems go along with a bad catalytic converter?
A clogged catalytic convertor causes the symptoms of a loss of power when accelerating or going up a hill. This is an often overlooked cause of loss of power, can cause check engine fault codes and lights, and mechanics will often change a few parts unnecessarily , especially if it is only partially plugged. A couple ways I check for plugged cats when a low power complaint is a symptom, and other obvious basic maintenance items have been checked for service is to have someone hold the rpm at about 1800 to 2000 steady. Then check for a good push of exhaust with my hand from behind the tailpipe. A plugged or partially plugged cat typically leaves a hot sickly feeling exhaust flow from the tailpipe. Compare to a known good working car nearby, known to be performing properly and with the same amount of cylinders. That slow , hot sickly flow at 2000 rpm compared to the hard push blowing your hand away of a not clogged cat is a dead giveaway, and I have NEVER misdiagnosed a plugged cat , or made false diagnosis with this method. Another way is watching a vacuum gauge connected to the intake manifold. When revving up, if the exhaust is plugged the gauge reading will climb then begin to slowly drop as the exhaust pressure builds up. Further testing will be needed to verify which part of the exhaust is plugged. Diagnostic by codes is unreliable and until now I had not heard of it. A code p420 only refers to catalyst efficiency. And can be set by faulty o2 sensors. Removing the exhaust and testing for engine power returning to normal works. But the hot sickly flow has been most accurate with my experience, in several cases where shops had missed it, were stumped and called me to come check. They are always embarrassed for missing the simplicity, but need not, as cars and their complicated electronics and even age old problems can lead to loss of power without any immediately obvious cause.
3rd Row Cadillac Escalade '07 seat won't come out?
The left hinge has the release cable going to it. You will have to get a flash light to look down in past the rubber slotted cover and use a long screwdriver to release the hinge. There is an updated hinge and cable available from GM Parts.
2002 Cadillac DeVille P0340 & P0341 Codes?
My car is giving these two codes. I cleared the codes and the came back. I then replaced the cam position sensor and cleared the codes again they came back. Is there anything else to check? Took it k n for an electrical scan they say it may be in the wire harness . I want to get some feedback before shelling out $200 or more for something that I can possibly do myself. Thank for any advice.
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.
Can the fuel/oil pressure switch cause the fuel pump to not come on?
I own a shop, and have done extensive fuel systems work. Most GM vehicles are wired through the oil pressure sending unit (located by the oil filter, or top back of engine) and is done so as a safety feature. When involved in an accident, the engine stops running. As it stops running, it also looses oil pressure, and since the fuel pump is wired through this switch, no oil pressure equals no fuel pump. When you turn your ignition switch to the on position, you hear the fuel pump come on momentarily for 3-4 seconds. This primes the fuel pump pressure that may have leaked off, but does not run the pump. The system has a momentary relay (latch) that pulls in when energised to supply the pump with power, but once the latch heats up, the circuit opens, and if no oil pressure is there, the engine doesn't run. One can test this circuit simply by purchasing a spray can of carburetor/choke cleaner, spray 3-4 seconds into intake of engine (with throttle held wide open). Remove spray, and start the engine. If it runs for a few seconds and stalls, repeat the procedure. This test primes the fuel system, checks the fire from the ignition, and isolates the problem to the fuel delivery system. All GM systems has a fuel pump test wire (usually around the brake booster or left fender) that is red. Connect a 12 (+) wire momentarily to this wire, and the pump should run as long as you keep this wire hooked up. Many fuel delivery problems can be resolved due to grounding issues such as; no ground strap from engine to fire wall, or no ground at tank to frame. Even the ground at the battery (-) terminal has a wire that bolts to the body, and/or the frame that can cause all kinds of problems. Finally the fuel pressure regulator can have a vacuum hose that is sucking air around the hose, cracked, fell off, collapsing, or clogged keeping the fuel pressure from building up enough to run the engine. As always; One must have a clean fuel filter, no leaks in the line, and the return line to the tank must be free, and without clogs. Glad to help out, Good Luck!!!
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 won't my Cadillac Cts accelerate?
While my car is running all of a it sudden won't accelerate the car engine is still on but it won't run.. it doesnr rev or make any noise.. i had to get it towed to my house.. please help! .