Idles but stalls when throttled - Troy-Bilt Garden

Throttle Body Cleaning on vehicles without electronic throttle control (most 2003 and down)

You can in most cases repair this slow speed stall or unstable idle by cleaning the engine throttle valve and the idle speed control valve using a product called CRC Spray Throttle valve cleaner. Spray the cleaner into the air intake of the engine with the hose removed from the throttle body, the engine will try to stall so hold up the idle speed manually. Once you have used up about 1/2 can of the cleaner stall the engine out while spraying and turn the key off, disconnect the negative battery cable for 5 minutes and then reconnect and drive the car for a about 25 miles of varied driving modes. If this doesn't cure the problem you may need the fuel injectors professionally cleaned by the dealer service dept.

Possible torque converter clutch issue. Is the check engine light on? If so, have it scanned for transmission codes. If the torque converter clutch is locked up when it isn't supposed to be, the vehicle will stall. Another thing to check is for coking on the throttle plate. Remove the hose that goes from the air filter box to the throttle assembly and look inside the throttle bore to see if it is dirty/black. If so, use carb cleaner and a toothbrush to clean while holding throttle plate open and remove as much carbon deposits as possible. This can affect minimum idle airflow and also cause a stall

idle air control (IAC) or idle control valve (ICV) same part, sometimes listed under one or the other when parts store looks them up. if veh has throttle body is located on passenger side of throttle body (rear side)

Try this

Here is the common cause of surges, cold stalls, stalls at stops, slow idle speed, erratic idle speed, rough idle and engine hesitation (and other problems), it is in most cases the idle speed control air-bypass valve and or throttle valve and upper intake, these area's get full of gunk and combustion residue over the miles and cause idle issues (stalls, low idle) like yours.

To correct this problem Buy a can of throttle valve cleaner (it is made by CRC) from the local auto parts store, NEVER USE CARB CLEANING SPRAY, IT DESTROYS THE ANTI-STICK TEFLON COATING, spray it into the air intake through the throttle body of the engine until you have used about half the can, you will need to hold the idle up while you do this, it will try to stall, after this shut the engine down and disconnect the Negative (-) battery cable for 5 minutes. The intake is now clean, if you continue to have the idle speed control problems you may need to seek the help of a professional.

This engine has automatic idle speed control, the computer controls a "air bypass" valve on the side of the throttle body where the air intake hose from the air cleaner is connected, the valve and the throttle butterfly get "sludged" up and this causes all kinds of idle problems and off idle stall, see full list below and fix for the problems

Here is the common cause of surges, cold stalls, stalls at stops, slow idle speed, erratic idle speed, rough idle and engine hesitation (and other problems), it is in most cases the idle speed control air-bypass valve and or throttle valve and upper intake, these area's get full of gunk and combustion residue over the miles and cause idle issues (stalls, low idle) like yours.

To correct this problem Buy a can of throttle valve cleaner (it is made by CRC) from the local auto parts store, NEVER USE CARB CLEANING SPRAY, IT DESTROYS THE ANTI-STICK TEFLON COATING, spray it into the air intake through the throttle body of the engine until you have used about half the can, you will need to hold the idle up while you do this, it will try to stall, after this shut the engine down and disconnect the Negative (-) battery cable for 5 minutes. The intake is now clean, if you continue to have the idle speed control problems you may need to seek the help of a professional.

Clean your Throttle body and pay attention to the Idle Air Control (IAC) valve passageway to try to clean the IAC. A dirty or faulty IAC will cause your engine to stall at idle, the job of the IAC is to open the passage way through the throttle body to regulate the amount of air to enter the engine to keep it from stalling when the Envoy is at idle.

Start with the simple and clean the throttle body and inspect any loose or damaged wire leads to the throttle body. Replace or repair any signs of damage.

Thank you for using Fixya and good luck.

Throttle position sensor, check this out. Also try cleaning the throttle body with throttle body cleaner may be all it needs'

Is it stalling at idle, or while driving? Have you performed a Throttle Body Service? The Tps usually wouldn't cause a stalling problem at idle, and it would generally throw a check engine light. The Idle air control valve, on the other hand, could be clogged full of carbon and not allowing any or enough airflow through to the enging. You should remove the throttle body, pull out the idle air control valve, and if it is dirty, clean thoroughly with any throttle body cleaner from a parts store.

check your transmission fluid,the motor will stall when fluid is low

Clean the throttle valve and the air bypass idle speed control valve, they get full of sludge and restrict air flow, this causes a low idle at times and the engine will stall, clean them by spraying carb spray into the throttle valve while the eng is running, have someone hold the idle high or it will stall, after using at least 1/2 can shut down and disconnect the battery for 5 minutes, this clears the memory and allows the computer to relearn idle strategy, the computer willl take a few days to relearn the idle, maybe 30 miles of mixed driving.