Reply. Symptoms. If you have a four cylinder, one glow plug bad will cause slight hard starting and a miss. The symptoms of a bad mass air flow sensor include a car that is difficult to start, bad fuel economy, a rough idle, lack of power especially when accelerating and sometimes a fuel smell from the exhaust fumes. See Also:  Differences Between a Dead Battery and Bad Alternator. Nobody will touch it as there are no engine lights or codes and the car drives smoothly. I’ve checked the code and got P0101 so MAF issue. If there is continuity the fan is bad. With a vehicle, there’s a lot of power under the hood. But when I removed the the battery lead the positive or negative the car stop idle. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins. I have a 2011 Mazda CX-7 I changed the coolant temperature sensor and the crank shaft sensor and the mass air flow sensor and the codes p0117 and p061b I can’t seem to find the problem. after engine is heated everything is fine. Therefore, if the mass airflow sensor goes bad then it will ultimately jeopardize the performance of the engine. Some of the electrical systems in your car would fry if exposed to raw current, which is where the alternator voltage regulator comes into play. The idea is to create a steady stream of current that can power the vehicle consistently. It will then relay this information back to the engine control unit. I appreciate. Once the vehicle does start, missing, rough idle, hesitation, and lots of white smoke until the engine warms. It could be any number of things; further diagnosis is needed. I’ve paid for three diagnostic tests and each test comes up without a failure code/issue. I have spent over 30k doing wrong thing. The parts cost should be between $50 and $320 while the labor costs will be anywhere from $30 to $70. My car was a 2012 Nissan Altima and it only took around 5 resets until the light never showed up again. Like other electrical components, the instrument cluster requires a certain amount of voltage to display all the information you need while driving. Some of the most common symptoms of the P0404 on Dodge vehicles include engine dying at idle, engine stalling, or rough idle. When you have a lean idling problem with your engine, this is the result of too much air and not enough gasoline getting mixed together in the internal combustion chamber. The good news is that voltage regulator failure is one of those problems that develop over time. It was reading 28.5 before I did the reset. When I buy the car in 2018 at has an valeo alternator on the car. I avg 210-220 miles per a 12.2 tank of gas. Have... Read more Whan engine is warm, it shuts off and won't restart. If you’re in a higher gear and take your foot off the gas, does the car slow down faster than usual? So helpful. For instance, if your code happens to be “P0101 – Mass Air Flow Sensor Circuit Range/Performance”, it’s pretty obvious the MAF is the root cause. 10 Reasons to Wear Seat Belts. You need plenty of power to keep the engine running. FIXD explains symptoms and severity of P0138. Driving with a busted regulator is taking a chance. I’d get that check engine light code read at a local parts store, which should give you a better idea of what’s going on. Hopefully, you can now identify the various symptoms that reflect a bad EGR valve and also how to … It’s actually a common reason for a CEL. #8 – Check Engine Light or Battery Light Comes On, Differences Between a Dead Battery and Bad Alternator. And restrain yourself from swapping components trying to fix the problem before knowing which part is causing you trouble. My cluster went in my car after that one of the air con Motors went in it and apparently holding fix that my battery kept on going flat the cluster kept on cutting in and out the aircon stop working only one side driver side was blowing cold air passenger side was blowing hot air and now there’s no power going to the alternator. This will cause the engine to simply not have enough power output for the current demands. So, the acceleration will begin hesitating because the engine is lacking an adequate flow of fuel. I have a Chevy sonic 2015. ) Â, P0178 Code (Symptoms, Causes, and How to Fix), 4 Symptoms of a Bad Oil Control Valve (and VVT Solenoid), 6 Symptoms of a Bad PCM (and Replacement Cost), 5 Symptoms of a Bad ECU (and Replacement Cost). I went to work on the Monday I when I arrived home the evening when I reach the drive way the car just switch off. The replacement cost of a mass air flow sensor can be anywhere from $80 to $390 if having a mechanic do it for you. Here are eight common signs to watch out for: A typical car battery should put out about 12.6 volts in an open circuit (car not running). There are various troubleshooting techniques that will help you diagnose this issue. It’s not made to handle that type of voltage. Make sure to check the solenoid operation and wiring as well. Lots of vehicles house their voltage regulators in the ECU these days, so it is likely there. Perhaps the engine is knocking from burning oil and coolant. When the regulator is mounted inside the alternator housing, you’ll have to remove that first to access it. The battery is a reservoir to store energy. The excess power doesn’t go to waste because it charges the battery. Sometime after market sensors built in China or India, looks like the oem, but the components were cheaply built and with different resistant, will not solve the problems. Looking for a good online repair manual? Engine Light ON (or Service Engine Soon Warning Light) Possible a noticeable fuel odor caused by the release of fuel vapors (3 Common Causes), Carb Cleaner vs Brake Cleaner vs Throttle Body Cleaner (What’s The Difference? recently i have had a noise/like something rubbing or crackling noise, (sorry hard to describe noise). The worst symptoms from a bad knock sensor will occur when internal engine components become damaged. I have a Dodge Grand Caravan that sometimes gets sluggish, and a red spark appears on the instrument cluster. This is understandable with a bad mass air flow sensor because it will cause the internal combustion chamber to have an inadequate mixture of air and gasoline. An engine's coolant system passes coolant fluid through a series of pipes to collect heat and radiate it from the radiator. Just a little it locks back up if not the cheapest to replace to simply not enough! Components and look for broken, bent, pushed out, or connector... 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