Common questions

Why is my Chevy Suburban rough idle and stalling?

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Why is my Chevy Suburban rough idle and stalling?

I ordered the part and when it came in I went to install it to find that the throttle body on my suburban did not have an IAC Valve on it (I have Pics). I climbed under the dash and put an adhesive spacer under the stop for the pedal and the problem is fixed for now. What is going with these vehicles? HELP!

What’s the idle rate on a Chevy Tahoe?

The vehical also seems to idle low 550rpm down to 400 and lower on occasion. I have attempted to locate the idle air valve but it doesn’t seem to have one in the location in the manual (on throttle body by altinator). I can only find what I believe is the Throttle position sensor in that location.

Can a surburban have a rough idle on cold start?

Fry- I have an ’02 Surburban that has a rough idle on cold start. Typically, the temps have to be 40 degrees or below for this to occur. It never happens during the warm spring, summer and fall months.

What kind of car stalls at idle speed?

I have a “Late” 2001 Suburban LT 1500 2WD that stalls when you are slowly moving the vehicle. It most commonly occurs when pulling into a parking lot at idle speed. The vehicle runs great at speed and if you hold your foot lightly on the accelerator it will not die.

When does a Chevy Suburban stall at low idle?

Low idle engine stalls occasionally. RPMs are at 500 dipping to 400 but they should be around 600 to 800 I believe. My truck was stalling and shutting off at stop signs or red lights. I had the throttle body clean and had no more issues. My Chevy suburban just stops when turning or at a stop.

Why does my 2002 Chev suburban vibrate when idle?

My 2002 Chev Suburban has a slight tremor or vibration when it is idle or at a red light. I have replaced the plugs, and added gas treatment, but it still vibrates. It noticed it right after a fillup with 87 octane gas, and wonder if it is a gasoline issue.It has 52k miles on it, and otherwise runs great.

Why does my Chevy Suburban stall after backing out of parking areas?

NO DTC’s, NO CEL. Having a problem with stalling. It usually happens after backing out of parking areas when vehical returns to idle while shifting from reverse to drive. It then become difficult to restart. Also during this issue if vehical doesn’t stall it starts exibiting erratic idle.

What causes a car to have a low idle?

A dirty throttle body may cause a lower than normal idle and an engine stalling condition can develop. Performing a throttle body service will generally correct this concern.

I ordered the part and when it came in I went to install it to find that the throttle body on my suburban did not have an IAC Valve on it (I have Pics). I climbed under the dash and put an adhesive spacer under the stop for the pedal and the problem is fixed for now. What is going with these vehicles? HELP!

Fry- I have an ’02 Surburban that has a rough idle on cold start. Typically, the temps have to be 40 degrees or below for this to occur. It never happens during the warm spring, summer and fall months.

I have a “Late” 2001 Suburban LT 1500 2WD that stalls when you are slowly moving the vehicle. It most commonly occurs when pulling into a parking lot at idle speed. The vehicle runs great at speed and if you hold your foot lightly on the accelerator it will not die.

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

Is the Check Engine light on during rough idle?

At times, the check engine light will activate during the rough idle. Sometimes the light flashes and goes off after a half hour or so, and sometimes it will come on and stay on for as much as a day or two. The burb always runs fine after warming up, even if the light stays on.

The vehical also seems to idle low 550rpm down to 400 and lower on occasion. I have attempted to locate the idle air valve but it doesn’t seem to have one in the location in the manual (on throttle body by altinator). I can only find what I believe is the Throttle position sensor in that location.

What kind of engine does a Chevy Suburban have?

My 1999 454 7.4 liter suburban LT turns over several times when cold before spluttering into life ( it then nees a bit of gas) and Idles roughly. i think it may have a slight missfire. is this a common problem.

My 1999 454 7.4 liter suburban LT turns over several times when cold before spluttering into life ( it then nees a bit of gas) and Idles roughly. i think it may have a slight missfire. is this a common problem.

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’s the code for intake manifold gasket on a Silverado?

I am not a mechanic, but know my way around engines and like to wrench. I have a completely stock 2001 Silverado with the 5.3L and was getting codes P0171 and P0174 lean bank 1 and 2 during the winter. I read that the intake manifold gaskets are a common issue with these motors because the ethanol in gas eats away the OEM plastic gaskets.

Is the 98 Chevy 5.7 misfire running right?

I have a 98 chevy 1500 5.7. The truck doesnt run right at all. Msifres bad under acceleration. Idle ok when misses when reving and accelerating. I did a full tune up including plugs, wires, cap rotor and a new distributor. With key on i have about 60psi fuel pressure but idleing i only had 50psi.

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 to do after replacing intake manifold gasket?

1. Spray carb or brake cleaner around the edge of the intake manifold to check the gaskets on each side. 2. Also spray around other components to check for vacuum leaks. (EGR valve and tubes, PCV valve, MAP sensor, throttle body, intake tube, etc). 3. Disconnect and clean MAP and MAF sensors with MAF cleaner as well as IAC valve 4.

What kind of traction control does a Chevy Suburban have?

2007 chevy suburban “Service traction control””Stabilitrak off””Rough idle””poor shift””multiple misfire””poor acceleration”‘serial number” Mechanic’s Assistant: Is the rough idle intermittent or consistent? Mechanic’s Assistant: Are you fixing your Suburban yourself? What have you tried so far?

Why does my car engine run rough while idling?

When your car engine runs as it should, everything should be smooth without any noise. When any number of things goes wrong, the engine can start running rough, especially while idling. By understanding the causes of a car engine that has a rough idle, you can resolve the issue easily.

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’s the idle RPM on my Chevy Suburban?

My 1997 Chevy Suburban (5.7) is acting up on me. When I start it up the RPM and idle seem fine. As I let it sit for a couple of seconds the RPM’s slowly begin to drop until they finally bottom out at about 1K. As soon as I put it into Reverse/Drive etc. the RPM’s drop below that mark and it struggles to stay running.

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 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

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 happens when fuel injectors are not working?

The engine does not make power. Engine does not want to start. Clogged fuel injectors diagnostics. Diagnosing dead or clogged fuel injectors is difficult because it acts the same than a bad coil, dead spark plug, broken spark plug wires and or electrical problem.

What causes fuel injectors to get gummed up?

Injectors also get gummed up with varnish and gunk which formed when fuel is left in the tank for long periods of time. How to unclog clogged fuel injectors. Although there are many products such as injection cleaning additives that claim it can clean or unclog a clogged fuel injector while it is in the engine, they cannot.

Why does my fuel injector make a bad sound?

Rough idling/engine stalling – uneven supply of fuel during idling can cause RPM to fall too low and result in stalling. For example have a listen to this bad fuel injector sound: In addition to performance issues, you will also have to deal with:

The engine does not make power. Engine does not want to start. Clogged fuel injectors diagnostics. Diagnosing dead or clogged fuel injectors is difficult because it acts the same than a bad coil, dead spark plug, broken spark plug wires and or electrical problem.

What causes a car to idle rough at idle?

A clogged fuel filter stops the engine from receiving the right amount of fuel causing the engine to be rough idle. Fuel filters are often pretty cheap, and you can easily get the fuel filter removed and replaced from a nearby mechanic or do it yourself if you have some knowledge. 6. Dirty Air Filter

What causes a car to stop when idling?

Unfortunately, if the actuator gets damaged, the engine will no longer receive signals that tell it at what speed it should operate when idling. Hence, it stops. The same thing can happen if the system gets clogged. Excessive carbon buildup can also prevent the more accurate measurement of engine speed.

When does a car have a rough idle?

November 27, 2017. It’s easy to tell when your car has a rough idle: When you start the engine, it won’t run at a steady rate. It may almost stall, or it may run at varying RPMs without your putting your foot on the gas, or it may do both.

What happens if you have a bad idle control valve?

Since the idle air control valve is supposed to manage the idle speed of the engine, a bad valve will certainly throw that out of whack. It will cause the idle speed to randomly fluctuate to different speeds rather than stay at one constant speed. The idle speed may be too high at one moment and then too low at other moments.

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.

What happens if a Chevy 6.0 engine goes wrong?

In case any of these go wrong, an engine can misfire. There are quite grave consequences when a Chevy 6.0 engine misfires. The engine could get damaged even more, or you might experience more emissions or witness lesser fuel efficiency. This issue is known to be there in various Chevrolet models.

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 rough engine idle or TDC code?

So, should the engine misfire, rough engine idle or (TDC) code; point to an air leak in the intake manifold gasket, following the below directions. A very common cause of a leaking intake manifold is the gaskets and bolts used from the factory.

Why does my GM V8 engine misfire when cold?

Because, GM V8 engines are very prone to a rough idle and engine misfire when cold. The check engine light may also come on, with codes P0300, P0171 and PO174. But, as the engine warms up, the engine misfire or rough idle tends to go away; which seems confusing.

What causes a GMC truck to have a rough idle?

Please discard PIP3232A. The following diagnosis might be helpful if the vehicle exhibits the symptom (s) described in this PI. • A cold rough idle that diminishes as the engine warms up. • Possible DTCS P0171, P0174, or P0300. • Random misfires at idle. The intake gasket seals may be leaking around the intake ports, causing a lean condition.

So, should the engine misfire, rough engine idle or (TDC) code; point to an air leak in the intake manifold gasket, following the below directions. A very common cause of a leaking intake manifold is the gaskets and bolts used from the factory.

Because, GM V8 engines are very prone to a rough idle and engine misfire when cold. The check engine light may also come on, with codes P0300, P0171 and PO174. But, as the engine warms up, the engine misfire or rough idle tends to go away; which seems confusing.

Why is my GM 4.8l engine running too lean?

The engine may be running too lean, due to a leaking intake manifold. Too lean means too much air and not enough fuel; according to the power control module (PCM) calculation. When the engine is cold, not all sensors function. As the engine warms up the oxygen sensors report the lean condition.

At times, the check engine light will activate during the rough idle. Sometimes the light flashes and goes off after a half hour or so, and sometimes it will come on and stay on for as much as a day or two. The burb always runs fine after warming up, even if the light stays on.

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Ruth Doyle