Why does my Chevy truck stall at idle?

Filter is not that old, and if plugged or if pressure regulator is malfunctioning, why do I never see fuel pressure at throttle body so much as waver lower than 12psi? Also, many times the lean condition will start just off idle so bad so that truck wil fall flat on its face and stall.

What causes a Chevy Silverado to run rough?

If an oxygen sensor goes bad, it can make your Silverado run too lean (or rich). A super lean running engine will often idle rough. Fuel Injectors. The fuel injection systems job is to atomize the fuel into fine mist.

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.

Can a bad idle control valve cause stalling?

3. Engine stalling The idle control valve, also commonly referred to as the idle air control valve, is an engine management component that is found in one form or another on the majority of road going vehicles.

Why does my Chevy truck shake at idle?

While the truck is idling with 02 lean, a quick shot of carb spray in the throttle body will cause the 02 to go rich. And when the truck sometimes starts shaking at idle it will smooth out with carb spray. I jst don’t understand why the computer is not trying to richen the mixture up based on the 02 saying lean.

What causes an Audi A4 to idle rough?

A super lean running engine will often idle rough. The fuel injection systems job is to atomize the fuel into fine mist. If a fuel injector has an issue with this process, it will either let too much or too little fuel into the combustion chamber relative to the amount of air.

What’s the fuel pressure on a Chevy long tern?

Long tern fuel trim seems to hang aroun 162-65 on a hot engine, short term fuel trim starts at 128 and sometimes goes to around 134. Vacuum at 2500 in park is around 20inches. Ok.. Verify there is 18-20 of fuel pressure when you dead head the fuel pump.

What’s the fuel Gage on a 1993 Chevy truck?

Fuel gage never wavered at 12-13 psi. MAP around 2.9v when PW 2.8MS when truck seemed to be falling a little flat under brake torque. This thing is really close to getting a carburetor on it.

Why is my GMC Sierra 1500 stalling and dying?

There is no code given. Have changed the injectors, timing, fuel tank, fuel pump, fuel pump, map sensor, cooling temp sensor on front of block, rebuilt the tbi, air idea valve. None of this hasite helped. The truck starts and dies. Have to give a little gas to keep running. While driving have to 2 foot it so it won’t die.

What causes the Check Engine light to turn off at idle?

At idle, the ECM will not get the correct information and the throttle will variate randomly causing idle surges. The check engine light will randomly turn on and off even if the car is running smoothly without any jerks and stalling.

Can a bad throttle position sensor cause idle surging?

Idle surging can be caused due to other issues in the car, but if it happens in conjunction with other throttle position sensor symptoms, the culprit is often the TPS. At idle, the ECM will not get the correct information and the throttle will variate randomly causing idle surges. 3) Check Engine Light

Why does my Dads 93 Chevy truck die?

My Dads 93 was doing what seems to be the same thing as yours. It ended up being the Fuel Pump Relay. If I press the gas pedal it dies. It’s been acting weird for a while now. For instance, when I take off from a dead stop at a light it sort of hesitates when I hit the gas.

What are the symptoms of a bad idle control valve?

$0.00 1 Irregular idle speed One of the most common symptoms commonly associated with a problematic idle air control valve is irregular idle speed. 2 Check Engine Light comes on Another symptom of a potential issue with the idle control valve is an illuminated Check Engine Light. 3 Engine stalling

What causes a car to run lean at idle?

If the root cause is an electrical problem within the idle air control valve itself, you will likely have to replace the IAC. A vacuum leak is a hole in a vehicle’s air intake system behind the mass air flow (MAF) sensor that allows unmetered air into the engine. This throws off the expected air fuel ratio and causes the vehicle to run lean.

Why does my GMC Truck die at idle?

Once the engine is warmed up then it relies on the O2 sensor for air/fuel ratio. A rough idle usually means a vacuum leak. I would check for those especially vacuum lines.

Why does my 1993 Chevy TBI stall at idle?

Timing is steady and not jumping all over. It is a fuel issue. The only code that ever sets is a P044, lean exhaust, and the exhaust is really lean. We have swapped PCM/PROM with a same year Suburban, no change. Both vehicles run the same as this did using the other’s PCM.

Why does my Chevy Silverado not idle after a cold start?

My 89 Chevy Silverado would not idle after a cold start I took the PCV valve out and sprayed it with carburetor cleaner….no more problems!!! 5 people found this helpful. One of the MOST overlooked parts of these TBI engines is the distributor pickup coil.

Why does my car stall at highway speeds?

The engine may start and idle fine, but run out of power or even stall at highway speeds. If the engine starts right back up after stalling, the likely cause is low fuel volume delivery because of a weak pump. If the engine is running normally one minute, but suddenly quits, loss of ignition may be the problem.

Can a car stall with a bad throttle position sensor?

The engine can stall for no reason and without any warning. This happens when the TPS gives incorrect information to the ECM. The engine can stall at high speed, at low speed, or even at idle. A faulty throttle position sensor will not let your car accelerate normally. Though this doesn’t happen all the time.

What happens when the throttle body goes bad?

Nowadays there is an electric system that’s far more efficient than the old ways but it can still have issues. When a TPS goes bad, then the car’s throttle body won’t function properly. It could either stay shut or it won’t close properly which is a severe issue. If it stays shut then your engine is not going receive air and it won’t start.

Why does my Chevy Trailblazer keep stalling out?

If your Chevy Trailblazer’s engine timing is off, it’s going to stall out, misfire, and altogether not run properly. Here are some of the more common causes of an engine timing problem:

Why does my GMC Truck die at idle when warm?

So I wasn’t suspicious of fuel pressure, then later checked it and I have a steady 10psi from the moment I turn the key until a few seconds after it dies so the fuel pump is good. It runs strong and is fine until I idle. This happens only when the engine is warm and last time I checked it never went into closed loop.

Why does my TBI die at idle when warm?

With 160K on the TB it was time for a rebuild and good cleaning. The throttle body has been rebuilt with new injectors, fpr, and orings. The idle is not high. It fluctuates and sometimes it cant recover from the drop in rpms and dies.

What makes a 91 Chevy surging at idle?

My father in law’s ’91 Chevy was running poorly, so we put new plugs, wires, cap and rotor on it, and it’s running better, but it it still surging at idle. It basically almost dies out, and then surges back to life (probably a little higher than normal idle), then repeats continuously until you apply some throttle.

What should the idle speed be on a GM TBI?

Insert a T-30 size Torx driver into the Idle adjustment screw that is located behind the plug removed earlier. Turn the screw to adjust the idle speed to 650 RPM +/- 50 RPM. Turn off the engine and disconnect the negative battery terminal from the battery using a wrench.

Why does my car stall at high speed?

The engine can stall at high speed, at low speed, or even at idle. A faulty throttle position sensor will not let your car accelerate normally. Though this doesn’t happen all the time. You may experience slow acceleration, acceleration surge at both high and low speeds, hesitation or delay in acceleration, and other related symptoms.

What is the diagnostic code for engine stall?

Diagnostic trouble codes P0120, P0121, P0122, P0123, and P0124 are what will commonly appear. The engine can stall for no reason and without any warning. This happens when the TPS gives incorrect information to the ECM. The engine can stall at high speed, at low speed, or even at idle.

How is the throttle connected to the accelerator?

In the old days, there used to be a cable that was connected from the throttle to the accelerator. But now in the technological age, the car’s computer controls when the throttle opens and closes by the feedback it gets about the acceleration of the vehicle.

What causes an engine to die while driving?

On deceleration, engine rpms may fall below normal idle speed and stall. When reaching a stop light, the engine may jerk and die. While driving, the engine may suddenly shut off.

What causes a Chevy C / K 1500 to drop in idle?

In order to change these, you have to completely removed the distributor and completely disassemble the distributor to get the pickup off and replace it. 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.

This is controlled by the engine’s computer. Sometimes parts go bad, which results in your car idling strangely or stalling. Check to see if your idle control valve is functioning properly before attempting to replace it. Look for a high engine idle. A common symptom of a faulty idle control valve can be a high idle.

Why is my Chevy Silverado running rough at idle?

Really, your Silverado will be running rougher at any RPM, but a misfire will be most pronounced at idle. Spark Plug Wires – While not every model and engine combination of vehicles today comes with spark plug wires (a lot are now coil on plug), if your Silverado happens to have them, they can go bad and cause a rough idle.

What causes a car to die at idle?

When a car dies at idle, the last thing that drivers think of is a problem with the spark plugs. Gasoline engines require these small gadgets to deliver a spark to ignite the fuel air mixture in the combustion chamber. If you have a diesel engine, then this is something that you don’t need to worry about.

What should I do if my Chevy truck dies?

Last test says to start the vehicle and remove the relay. The vehicle should continue to run (which it did not because it died in seconds). If the vehicle stalls check the fuel pump/oil pressure switch and its wiring. Book does not say where fuel pump/oil pressure switch is.

What to do if your car dies while idling?

Engage the parking brake, start the engine, and let it idle. Pop the hood open. Wiggle the battery cables, including the small wire that connects to the car’s body, if your vehicle has one. If the engine shuts off and the headlights stop working while you do this, you are dealing with a loose, corroded or frayed cable or wire.

What to do when your Chevy Silverado wont idle?

Check if the EGR valve is stuck open or the gasket is leaking. To check if stuck open, you should be able to get your fingers on the underside and move the diaphram. Also disconnect and plug off the vacuum hose. You shoud look close at the TPS connector wires. Give a tug on each little wire to see is one of them stretches.

Why does my car idle rough all the time?

3. Dirty Fuel Injector. Sometime dirty parts can also be the root cause of a rough idling engine. Fuel injectors disperse fuel into your vehicle’s engine at a precise angle and quantity, to ensure optimal performance. That being said, dirty fuel injectors are also a major contributor to poor gas mileage.

What should you do if your car idles for a long time?

How your engine idles is a good indicator it its overall health; addressing the problem sooner rather than later and checking all potential causes is important. If you’re unsure what the problem is, it is always a good idea to call in the professionals for a diagnosis.

Why does my Chevy Blazer have a rough idle?

What are common reasons my Chevrolet Blazer has a rough idle? While there are a variety of reasons your Chevrolet Blazer has a rough idle, the most common 3 are a vacuum leak, an issue with the spark plugs, or a problem with the ignition coil. See what others are asking about their Chevrolet Blazer.

Why is my 5.3 L missing and rough idle intermittently?

5.3 L Missing and Rough Idle Intermittently I have changed Spark Plugs,Wires ,Coil Packs, and removed Fuel Injectors and soaked overnight. Engine code is a P0304. Misfire Cylinder #4. Most of the time around town is alright. When i put it on highway, it will surge like its cutting off and then pick right back up and be fine. Fuel Presure is 55 psi.

What makes a Chevy C / K 1500 stutter at idle?

Try removing the 2 injectors from the TBI and there’s one fine small plastic screen on the bottom of each injector. These will be dirty. They catch smaller particles the iinline fuel filter and screen inside the fuel tank miss. The right fuel pressure doesn’t mean anything if these are dirty.

What should fuel pressure be on 1993 Chevy TBI?

Verify there is 18-20 of fuel pressure when you dead head the fuel pump. If low, verify there is good power and ground to the fuel pump and that the fuel filter is clear. Also, make sure that the MAP sensor vacuum port in the throttle body is not restricted.

When is a bad throttle position sensor a warning sign?

Engine won’t idle smoothly, idles too slowly, or stalls If you start to experience engine misfires, stalling, or rough idling when the car is stopped, it can also be a warning sign of a failing TPS. You don’t want to wait to get this checked out!

Where is the idle button on a GM TBI?

The “A” and “B” terminals are located on the top right of the connector. Unplug the IAC valve located on the passenger side, rear of the throttle body. Start the engine. Insert a T-30 size Torx driver into the Idle adjustment screw that is located behind the plug removed earlier.

What was the initial problem with my truck?

The initial problem was the truck stalled and died. The following parts have been replaced: spark plugs, wires, fuel filter, distributor, cap, rotor, pick up coil, map sensor, throttle position sensor, and idle air control valve.

Why does my Chevy Silverado lose engine power?

Keep reading to find at least one possible answer to “Why is my Chevy Silverado losing power?” Read More: How Can You Tell If Your Pickup Is Overloaded? If your GM truck occasionally loses the ability to accelerate and warns you of reduced engine power, that could be caused by a faulty throttle body.

What causes a truck to hesitate when accelerating?

Hesitates When Accelerating: the Initial Problem Was the Truck The initial problem was the truck stalled and died. The following parts have been replaced: spark plugs, wires, fuel filter, distributor, cap, rotor, pick up coil, map sensor, throttle position sensor, and idle air control valve.

What causes the idle speed to go up or down?

The idle air control valve is programmed to regulate and maintain the engine idle speed at a constant rate. If the valve fails or has any issues it can cause the idle speed to be thrown off. This may result in an unusually high or low idle speed, or in some cases a surging idle speed that repeatedly climbs and falls. 2. Check Engine Light comes on

What causes a Chevy 350 to backfire when idle?

If a main vacuum hose such as the power brake booster feed line has broken or failing off it will cause a lean backfire due to the additional air allowed into the engine intake manifold. This problem will be accompanied by high or low engine idle and a harder to push brake pedal than normal.

Why does my Chevy k1500 stall when gas is released?

I have been working on our 89 Chevy K1500 and am still having an idle issue. The truck idle drops and lopes and occasionally completely stalls. This usually happens when driving slow in town… backing out of parking space, letting off gas when coming to a stop sign or to park etc. It does fine to start and accelerate.

What should fuel Gage reading be at idle?

The 02 reading starts out at idle a little biased lean, but switching, then as soon as into accelerator truck stays lean until open loop. 58-65 mv is normal when leans out. Fuel gage never wavered at 12-13 psi.

What to do if your car stalls while idling?

If air can’t go through the air ports when needed, the engine may stall when you reach a stop or while the engine is idling. Locate the IAC around the throttle body. Unplug the IAC solenoid electrical connector. Remove the solenoid from the throttle body.

Why does my 98 Dodge Dakota not idle?

Had the same problem with my 98 Dakota. It was just the Negative battery end. For some reason when the cable end is not clean and tight it will not idle. 28 people found this helpful. Idle air control valve its on backside of throttle body take out and clean it or replace only 38 bucks at auto my 92 had the same problem

How often does my Chevy Colorado engine stall?

When coming to a stop the rpm drops to 500 and feels like it is going to stall. It then jumps back up to about 750, but idles rough. The engine completely stalled one time as I was braking coming off of a freeway off-ramp into a turn. The check engine light has come on twice, but went out on the next drive. This has been over a two week period.

What causes a truck to stall when gas is released?

The truck idle drops and lopes and occasionally completely stalls. This usually happens when driving slow in town… backing out of parking space, letting off gas when coming to a stop sign or to park etc. It does fine to start and accelerate. I have done a tune up including oil and filter, fuel filter, spark plugs, wires, cap and rotor.

Why does my 91 Chevy 1500 die at idle?

WORKING ON MY 91 CHEVY 1500 4BY4 . MY PROBLEM IS THE MOTOR DIES AT IDLE IT HAS THE 5.7 TBI. WHEN YOU LET THE MOTOR WARM UP IT WILL JUST DIE OUT AFTER ABOUT 5 MINUTES IDLE TIME BUT WILL START RIGHT BACK UP THEN DIE AGAIN MAYBE 2 MINUTES LATER. IF I PUT IT RIGHT IN DRIVE AND GO IT WILL RUN FIND UNTIL I HAVE TO STOP THEN IT WILL DIE OUT AGAIN.

Why does fuel pressure increase when the engine is idle?

Due to this vacuum hose, when the vehicle is in an idle condition, there is less pressure against the fuel coming inside the regulator. When the vehicle accelerates, the fuel entering the regulator increases. This is how the fuel requirement in the engine is served accordingly.

Fuel gage never wavered at 12-13 psi. MAP around 2.9v when PW 2.8MS when truck seemed to be falling a little flat under brake torque. This thing is really close to getting a carburetor on it.

Why is my fuel pump not producing pressure?

The fuel pump is able to create pressure using electricity but if it is not getting the adequate voltage of electricity it will not be able to function properly. Consequently, the fuel will not be released at the perfect pressure and your car will lose efficiency.

Why does my Chevy truck stall at idle?