Hard start, rough idle, then idles fine, acts like not getting fuel, has new fuel pump
So my car has a rough start, bad idle, then idles fine but when I push on the gas pedal it acts like it is not getting fuel
My car has 160555 miles.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
Hello there, thanks for writing in. Many faults will cause a rough starting and lack of power with your 2001 Toyota Corolla. The most likely causes of this are a clogged fuel filter, spark plugs, coil, failed fuel injectors, wiring harness fault, vacuum leak, MAF sensor, or oxygen sensors. A qualified technician such as one from YourMechanic will be able to diagnose your loss of power and make any repairs required to resolve the issue and get you car back to normal.
How to Identify and Fix Common car Problems ?
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The most common reasons a Toyota Corolla has rough idle are a vacuum leak, an issue with the spark plugs, or a problem with the ignition coil.
A rough idle is one symptom of a clogged fuel filter. Failing Electrical Components: A problem or failure in the ignition system or various electronic components can cause a rough idle. If this is the case, the problem will usually get worse as RPMs increase.
The most likely causes of this are a clogged fuel filter, spark plugs, coil, failed fuel injectors, wiring harness fault, vacuum leak, MAF sensor, or oxygen sensors.
What to Look For: A bad fuel pump can cause difficulty when starting the vehicle, a rough idle, and stalling. Clogged Fuel Filter – The fuel filter filters the contaminants from gasoline. Over time it can become clogged, which slows the flow of fuel.
Oxygen (O2) sensor An oxygen sensor monitors and analyzes the amount of oxygen in a vehicle`s exhaust system after combustion. A dirty, damaged or malfunctioning O2 sensor (or sensors) affects the air/fuel mixture, causing the engine to idle rough.
Engine Misfires Perhaps the single most common cause of rough idle comes in the form of a misfiring engine. As you may know, any automotive engine contains multiple cylinders. Each of these cylinders contributes to powering your car by combusting a mixture of gasoline and air.
A difficult start could be due to a number of things, from a dying battery to a faulty starter. But if your vehicle has a hard time starting after sitting for just a few hours, it can cause an extra layer of confusion. When this happens, one of the most common causes is low fuel pressure.
If your vehicle won`t start, it`s usually caused by a dying or dead battery, loose or corroded connection cables, a bad alternator or an issue with the starter. It can be hard to determine if you`re dealing with a battery or an alternator problem.
Common reasons for this to happen:
Tire replacement, realignment, and rebalancing are common solutions. Engine firing issues: When one or more of your spark plugs isn`t firing correctly, it can cause your car to vibrate. Typically, this problem will also cause your check engine light to illuminate.
Oil changes keep your car engine running smoothly. Rough idling, slow acceleration, and engine noises mean you need to replace your car oil.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Hard start, rough idle, then idles fine, acts like not getting fuel, has new fuel pump
ANSWER : Hello there, thanks for writing in. Many faults will cause a rough starting and lack of power with your 2001 Toyota Corolla. The most likely causes of this are a clogged fuel filter, spark plugs, coil, failed fuel injectors, wiring harness fault, vacuum leak, MAF sensor, or oxygen sensors. A qualified technician such as one from YourMechanic will be able to diagnose your loss of power and make any repairs required to resolve the issue and get you car back to normal.
Not getting enough fuel car will not run right. It stalls when you give it gas and stalls when it’s running. It’s a 1984 Ford Escort.
ANSWER : Hi there, thanks for writing in. Several early 80’s Ford’s swapped from carburetor to fuel injected engines; including your ’84 Ford Escort. However, there were two different fuel systems available that year. If your Escort has the fuel injected engine, one item I’d check is the EGR valve or clean the throttle body.
Both systems impact fuel delivery into the engine and if they are dirty or clogged with excessive carbon build up, can starve the engine to create this type of issue. If it’s the carburetor version, the carburetor might need to be rebuilt, or may be an issue with float bowls inside the carb.
If you need assistance diagnosing the exact issue, feel free to contact one of our professional mechanics to complete an engine is stalling inspection firsthand at your own location.
Just replaced my fuel pump but its not getting any power tested fuel pump relay and fuel fuse both good tested the wires all good.
ANSWER : You need to look at the theft light on dash to make sure it comes on and goes off when you turn the key to the on position. If light comes on and stays on then your theft system is causing the fuel pump to not be engaged. I recommend you check the theft system and then scan the computer for theft system codes. You may need to reprogram the keys to work or you have an bad sensor for the ignition key in the steering column.
I have a truck that won’t run and is not getting gas to the engine. Fuel pump is running, have a new filter and new fuel pressure
ANSWER : Hi There,
It sounds like you may have a clogged fuel injector or potentially a faulty injector that is fried internally. I would suggest testing them if you have access to a multi meter. Disconnect the injector from the electrical connector and set your multi meter to Ohms mode and measure the resistance of the injector. After testing all injectors, compare the resistance. They should be the same or very close. If they are not, they will likely need to be replaced.
Ok car starts and runs fine normal idle but once it gets up to warming temp it’s like it starts to bog and dies.
ANSWER : With the randomness of the codes you are pulling, it is hard to determine what they have in common. When diagnosing mechanical errors like this, keep it simple. Due to the loss of power and stalling issue, I would like you to look at the one component that may have a huge effect over all of theses parts.
The ELD is a unit which measures the amount of power coming from the battery. It allows the alternator to adjust the field, and the amount of power generated by it. If you are experiencing issues with the ELD, which allows the battery and alternator to behave incorrectly, the other electrical components in the vehicle will not work. You may have more than one issue that is all coming to a head at once.
You can test the ELD with a multimeter, but any electrical testing can be dangerous, and we recommend you proceed with caution. If you’re not comfortable with this repair, consider YourMechanic, as one of our mobile technicians can come to your home to diagnose the stalling issue firsthand and help you make the necessary repairs.
the car is acting like its getting to much fuel. changed the fuel pump, fuel filter, and the fuel pump relay.
ANSWER : There could be a few things contributing to your problem. You are correct that clogged or sticking fuel injectors and possibly the fuel pressure regulator could be faulty. A plugged catalytic converter can also cause the vehicle to bog down. A failing throttle position sensor can cause the symptoms you describe as well. I suggest having a certified technician, like one from YourMechanic.com, do a few tests to determine the exact cause of your starting concern.
Installed new delphi fuel pump and fram fuel filter. still no pressure on fuel rail valve and wont start. 2003 Chevrolet Tahoe
ANSWER : Hi there – I suspect you have weak power getting to the fuel pump. I would first check the voltage coming out of the fuel pump relay. If the contacts in the relay are burned, you will not get reliable current flow to the pump. Check the fuel pump ground as well (voltage drop across the ground, not just continuity). I recommend a fuel system inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.
I changed fuel pump and truck ran great for 3 days. Now after 3 days truck dies. It will start runs few min then dies like before
ANSWER : Check the bottom of the fuel tank for sediment. Age and mileage could have accumulated a lot of it at the bottom of the tank. If you did not, check and change the fuel filter. Rule of thumb – replace the fuel filter any time you replace a fuel pump. Also, check the wiring for any chaffing on the fuel pump when you remove it. While your problem is kind of unique, I have seen many GM truck fuel tank baffle loosen over time, occasionally rubbing against the fuel pump can intermittently short it out and/or block the fuel pump pick up. To have this diagnosed, consider having a certified expert from YourMechanic inspect the stalling issue to have this corrected.
