Common questions

Why does my Chevy 350 Backfire at high RPM?

Why does my Chevy 350 Backfire at high RPM?

The 90 degree elbow in the PCV Valve hose at the base of the throttle body to the PCV valve is common to either fall off or have a hole in it. Most of the time the engine will idle at a higher RPM a suction sound can be heard.

What causes a car engine to backfire with low gas mileage?

On older engine’s ignition timing is set at a specific degree in relationship to the crankshaft. If this timing is mis-adjusted it can cause low power, poor gas mileage, engine detonation (pinging) and backfiring through the intake or exhaust system.

What causes a Chevy C / K 1500 to bog down?

My truck bogs down (and tries to die) when I give it gas to accelerate off of a stop. There is often a backfire or two when this happens. Pumping the gas does not help. I basically have to crawl through any intersection until it picks up a bit of speed from idle. The truck idles smoothly, and it runs fine once it’s above about 5-10mph or so.

What are the most common signs of engine misfires?

The most common situation to notice misfires is on high gears, low RPM, and the accelerator to the floor. Rough acceleration is a typical sign that your engine is misfiring.

The 90 degree elbow in the PCV Valve hose at the base of the throttle body to the PCV valve is common to either fall off or have a hole in it. Most of the time the engine will idle at a higher RPM a suction sound can be heard.

Why is my Chevy Suburban bogging down on hard acceleration?

I have a 97 Suburban 5.7, 2wd. On hard acceleration it is bogging down like there is to much air, because sometimes it backfires. Or a plugged exhaust. I replaced the fuel pump-because it was bad in July.

Why is my GM Vortec engine bogging down?

If so look into a vacuume leak or possibly bad igntion components. If your not using delco plugs in this motor that can be a big contributor to your problem. GM vortec engines hate anything but vortec plugs and will do all kinds of weird things. And yes a clogged converter could cause this sort of thing to happen.

My truck bogs down (and tries to die) when I give it gas to accelerate off of a stop. There is often a backfire or two when this happens. Pumping the gas does not help. I basically have to crawl through any intersection until it picks up a bit of speed from idle. The truck idles smoothly, and it runs fine once it’s above about 5-10mph or so.

Why does my smallblock Chevy have no power?

If it doesn’t, and you find no other issues such as fuel starvation or exhaust restrictions, your camshaft could be excessively worn. Many older, higher mileage smallblock Chevys develop flattened cam lobes over time, resulting in lack of power and, sometimes, backfiring and the like. Lack of power is the most common symptom of flattened cam lobes.

Why does my Chevy 350 have no power?

If it doesn’t, and you find no other issues such as fuel starvation or exhaust restrictions, your camshaft could be excessively worn. Many older, higher mileage smallblock Chevys develop flattened cam lobes over time, resulting in lack of power and, sometimes, backfiring and the like.

When does a worn down camshaft lobe show up?

If a camshaft lobe is halfway worn down, it will show up only when the engine is running and under load.

Why does my car stall at low rpm?

The will likely force your computer to stall the engine and only allow it to run at low RPMs, which means the car will only move at slow speeds. This is a safety feature enforced by the computer so that your engine doesn’t get too damaged.

Why is my car losing power at low speeds?

If the pressure is low the fuel injectors will not be able to spray the correct amount of fuel into the combustion chamber and that will result in a loss of power. A faulty fuel pump will not pose problems at low speeds but when you are looking for quick acceleration you might be left wanting.

Why is my Mazda not getting full power?

A stretched out throttle cable in a Ford or Mazda can cause that.Take a look at your throttle cable. See if the pedal moves up and down and has “slack”. If so, your throttle might not be opening all of the way so you are not getting full power. If you floor the car the throttle might only be open 80%.

How to diagnose engine backfires with axleaddict?

Car owners usually forget to check the ignition system at the recommended manufacturer schedule. If necessary, consult your car owner’s manual or repair manual. Even if your Check Engine Light is not lit on your instrument panel, scan for possible pending diagnostic trouble codes that can guide you in your diagnostic. II. Injection System Problems

What causes a car engine to backfire at idle?

Using a smoke machine or carburetor cleaner you can check for a vacuum leak and repair it to fix the problem. A repetitive backfires are generated when the engine is simply running at idle or at cruising speed and can be inline with the engine RPM. A rhythmic popping sound which is not as prominent as lean under power backfires.

How can I tell if my engine is having a backfire?

Valve issues may also involve poor fuel economy, rough idle, stalling, high oil consumption, hard starting, and exhaust smoke. Valve problems of these type tend to create a more consistent backfire condition. You may diagnose valve problems at home with the use of a compression gauge or a vacuum gauge.

Why did my GM 454 Backfire at WOT?

I replaced the in tank fuel pump last month thinking it was fuel starvation while going up hills at WOT (wide open throttle). The fuel pressure with the old pump was low showing around 8 psi on the pressure gage that I permanently mounted 3 inches from the throttle body on the pressure line.

Is the GM 454 a throttle body injection?

I’mpretty sure Tim’s is a throttle body injection like mine. These look like a carb but are far from it. For that period it was GM’s answer to a carb and I think they worked better than a carb, but they came with their own problems. I’m having problems with my engine which is a gen 5 454 tbi 220 model made in 1992.

What can cause a backfire through the intake system?

Although there are many problems that can cause the intake system to backfire, the overall effect is the same. Since the intake valve needs to provide the engine with a proper balance of fuel and air, a backfire occurs when that balance fails.

What causes an intake back fire in an engine?

This will help locate the system that is having a problem and needs repair. An intake back-fire explosion can be caused by the fuel air mixture being to lean when the engine is demanding power. Every internal combustion engine runs on a mixture of 14 to 1 which is fourteen parts air to one part fuel.

What causes engine knock on a 4.3L Vortec?

Engine knock can be caused by a ton of factors, such as low-grade fuel, bad spark plugs, carbon build-up, etc. Engine knock is terrible for your engines internals and can cause serious damage to the pistons and to the cylinder walls. On the 4.3L vortec, the cause of the engine knock has not necessarily been figured out, still to this day.

Where are the intake gaskets on a Chevy Vortec?

The intake gaskets on the LB4 and L35 vortec’s are very prone to going bad which results in engine leaks, overheating, stalling, etc. The intake gasket sits between the intake manifold and the cylinder head.

What causes engine to backfire after camshaft is installed?

Many things can cause engine backfires, below we will go over a few things that can cause backfires after a camshaft is installed. Double check valve adjustment. Over adjusted lifters can hold valves open and cause the engine to backfire. A leak down test can help determine if valves are being held open.

Can a worn out timing belt cause a backfire?

A worn out timing belt can upset the combustion process and lead to backfires. Gasoline engines need to fire spark plugs on time to properly ignite the air-fuel mixture inside a cylinder. On time means that sometimes the spark needs to be fired ahead in advance or retarded depending on engine speed and load conditions.

What causes the catalytic converter to turn Cherry Red?

Hesitation and backfiring will accompany the loss of power causing the plugs to foul leaving them with a black “sooty” appearance. The unburned fuel enters the catalytic converter, causing it to overheat and turn cherry red. Over a short time this will cause the converter to fail.

This will help locate the system that is having a problem and needs repair. An intake back-fire explosion can be caused by the fuel air mixture being to lean when the engine is demanding power. Every internal combustion engine runs on a mixture of 14 to 1 which is fourteen parts air to one part fuel.

I replaced the in tank fuel pump last month thinking it was fuel starvation while going up hills at WOT (wide open throttle). The fuel pressure with the old pump was low showing around 8 psi on the pressure gage that I permanently mounted 3 inches from the throttle body on the pressure line.

I’mpretty sure Tim’s is a throttle body injection like mine. These look like a carb but are far from it. For that period it was GM’s answer to a carb and I think they worked better than a carb, but they came with their own problems. I’m having problems with my engine which is a gen 5 454 tbi 220 model made in 1992.

What causes an intake back fire in a car?

If the check engine or service engine soon light in on scan the computer for trouble codes. This will help locate the system that is having a problem and needs repair. An intake back-fire explosion can be caused by the fuel air mixture being to lean when the engine is demanding power.

If the check engine or service engine soon light in on scan the computer for trouble codes. This will help locate the system that is having a problem and needs repair. An intake back-fire explosion can be caused by the fuel air mixture being to lean when the engine is demanding power.

What makes a 95 TBI Chevy run crappy?

2–EGR….did you use the VIN # and go to the dealer for the correct one? to test it ,disconnect the vacuum line and plug it and go for a ride. 3–When I removed the cat on mine ,the 02 sensor set the check engine light on and was going thru more gas but didn’t run crappy.

What causes an exhaust tail pipe to backfire?

An exhaust tail pipe backfire is caused by an excessive amount of un-burnt fuel remaining in the exhaust system or fresh air being allowed to enter the system which ignites a small amount of un-burnt fuel. If fresh air is allowed to leak into the exhaust system it will ignite the un-burnt fuel inside the system creating a popping noise.

Can a bad spark plug cause an engine to misfire?

If you have separated spark plugs, unplug each coil to see if you can find out if any cylinders are not responding. Replace if you find one faulty or have a trouble code stored for one ignition coil. 2. Bad Spark Plug The second most common cause of a misfire is bad spark plugs.

How can you tell if your car engine is misfiring?

Rough acceleration is a typical sign that your engine is misfiring. Sometimes, the engine will misfire on idle also; your engine sensors will get faulty values, and the air-fuel mixture will get messed up. This can cause a very uneven idle, which can jump up and down, and the engine may also shut off on idle.

What causes an engine to misfire on all cylinders?

Low fuel pressure will cause a lean mixture in your engine which will result in misfires on all cylinders. If you have trouble codes for misfires on all cylinders, you will want to check your fuel pressure. 5. Injector Problem Another problem, which was more common five years ago, is injector problems.

What causes hesitation and stumbling in a 1990 Chevy c1500?

An expert that got 10 achievements. Re: 1990 chevy c1500 hesitation and stumbling during… Based on what you said, I would say the engine is starving for fuel. The computer has to be disabled to set timing – there should be a procedure for that. I would start with checking fuel pressure at the throttle body.

Why does my Chevy truck sputter when I accelerate?

The engine starts and runs fine, when I leave for or from work. But when I accelerate out of the parking lot it hesitates and really sputters. If you try to accelerate more it backfires a few times and then takes off like there’s nothing wrong.

What causes a Chevy C / K 1500 to stall?

These components are very sensitive and when failing, will cause misfire, idle issues, and cause it to burn rich as well. 11 out of 12 issues like this are because of this pickup coil. Pcv valve cleaning is general maintenance. 8 people found this helpful. CHECK THE DISTRIBUTOR TIMING!!

Why does my Chevy c1500 not start up?

SOURCE: No fuel to the injectors on a 1997 Chevy c1500. can be the distributor or maybe the fuel pump let the truck sit and then turn key almost on but not enough to initiate start up and see if you hear pump in the gas tank and if thats not it, it could very well be your distributor it might be moist in the cap or button area

Can a bad crankshaft sensor cause a cylinder to misfire?

Should you feel or hear a brief stutter in the engine, it may be a sign of misfiring cylinders from a bad crankshaft position sensor. A failing crankshaft position sensor cannot provide the right information about piston positioning in the engine, causing a cylinder to misfire.

Can a bad TPS cause an engine to shut off?

Acceleration issues: A bad TPS may cause all sorts of power issues. Your engine may start up but it will have little to no power and it causes it to shut off. Unstable Engine Idle: Faulty position sensors can cause sporadic idle conditions due to fluctuating airflow.

Why does my Chevy Silverado turn over but not fire?

145 people found this helpful. Have a 99 Chevrolet 4×4 Silverado with 5.0 it was hot wired by previous owner. It did crank but replaced the steering wheel column with new wires and now it will turn over but won’t start. The fuel pump is connected directly to the battery.

What kind of truck won’t start or fire?

I have a 1997 Chevy Z71 just put new trans in drove for about 20 miles and the truck just died………Replaced fuel pump, Fuel relay and found that the fuel fuzz blows every time I turn key on ???? 24 people found this helpful. 22 people found this helpful.

How to troubleshoot a transmission problem in a Chevrolet?

1 Symptoms. The first sign that you may have a possible transmission problem could be the check engine light coming on. 2 Troubleshooting Steps. The first steps in troubleshooting the Chevrolet transmission problem are to read the fault codes from the Transmission Control Module (TCM) and check the transmission fluid level. 3 Common Problems.

Why does my Chevy transmission not go into 3rd gear?

Chevy transmission won’t shift, stuck in 1st gear or limp mode – Speedometer may also display zero at all times. It could be internal transmission failure, low transmission fluid, or faulty Vehicle Speed Sensor (VSS sensor). Chevy transmission won’t go into 3rd or 4th gear – This is a good indication that 3 or 4 gear clutches are worn.

What are the symptoms of a bad throttle position sensor?

Symptoms Of A BAD Throttle Position Sensor (TPS) Beside the CHECK ENGINE LIGHT (CEL) being on and driving you nuts, your Chevy or GMC pick up (or SUV or van) may be experiencing one or several of the following symptoms: TPS diagnostic trouble codes (DTC’s) stored in the vehicle’s computer’s memory.

How does the ignition work on a Chevy 350?

The engine’s ignition system is triggered by an electronic driver which signals the ignition coil when to fire. By design the resistance it takes to fire the coil via the spark plug is figured into the system.

How does the throttle position sensor work on a GM Truck?

Like the majority of throttle position sensors on modern fuel injected cars and trucks nowadays, the GM TPS is a three wire sensor. Each wire provides a specific type of signal to the TPS or to the PCM (Powertrain Control Module=Fuel Injection Computer). Below are the circuit descriptions of each:

Are there any performance issues with the Chevy 350?

There are no significant performance issues related to the Chevy 350 engine’s design. Few problems are also founded in overall performance of used engines as long as they have been well-maintained or are aftermarket crate engines.

What causes a Chevy 350 engine to overheat?

According to hotrodders.com, one common problem is overheating, which is less of an engine ailment and more of radiator or thermostat issues. Owners should determine whether the radiator matches the 350, especially since the engine probably came from a different make and model car. The wrong thermostat also may have been previously installed.

When did the Chevy 350 engine come out?

The Chevy 350-cubic-inch engine has perhaps been General Motors’ most popular engine since its introduction in 1967. It’s no longer produced for new GM cars and trucks, but can be purchased as a replacement engine.

How to troubleshoot an overheating Chevrolet 350 engine?

Twist off the radiator cap after allowing the engine to cool, then look into the radiator to observe the level of antifreeze. Pour antifreeze into the radiator until full if necessary. With the radiator cap off, start the engine and look through the radiator opening while the engine warms.

What causes the fluid level to drop on a Chevy 350?

The drop is caused by the thermostat at the end of the top radiator hose opening. Replace the thermostat if the fluid level does not drop. Look for white smoke exiting from the exhaust pipe, which indicates a blown head gasket.

The engine’s ignition system is triggered by an electronic driver which signals the ignition coil when to fire. By design the resistance it takes to fire the coil via the spark plug is figured into the system.

What kind of car is 94 Chevy Silverado?

123 people found this helpful. My 94 Chevy Silverado was also sputtering, backfiring, missing etc…

What should I do about my 1994 Chevy Silverado?

My 94 Chevy Silverado was also sputtering, backfiring, missing etc… I changed the fuel filter to no avail, tried several things to get it to run smooth but nothing helped’ until a friend of mine who used to have his own shop told me about a memo he had received years ago dealing with this identical problem. here’s what worked for me!

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Ruth Doyle