Symptom Chart(s)

WARNING: This page is about a different car, the 2024 Ford Transit-350 HD, 2024 Ford Transit-350, 2024 Ford Transit-250, and 2024 Ford Transit-150. However, it is still accessible from the selected car via links, so may be relevant.

Symptom Chart: Symptom Chart - Exhaust System

Diagnostics in this service information assume a certain skill level and knowledge of Ford-specific diagnostic practices. For information regarding Ford-specific diagnostic practices, REFER to: Diagnostic Methods .

Verify the customer concern. Inspect the components of the exhaust system for obvious signs of damage or other mechanical concerns using the following chart.

Visual Inspection Chart - Mechanical

Mechanical
Exhaust pipe pinched or crushed Damaged resonator Damaged muffler Broken or damaged exhaust hanger brackets Damaged catalytic converter Loose or damaged heat shields

Verify the exhaust system is installed correctly, with clamps correctly located and tightened to specifications. If the fault is not visually evident, determine the symptom. GO to Symptom Chart below.

Symptom Chart

Condition	Possible Sources	Actions
Vehicle has low or no power -- vehicle performance concern	Exhaust pipe pinched or crushed Damaged catalytic converter Loose obstruction in exhaust system	REFER to: Catalyst System .
Vehicle has low or no power -- vehicle performance concern	Restriction in exhaust system (possible frozen condensate in muffler)	CHECK drain holes for foreign material. PARK the vehicle inside to thaw. TEST the vehicle for normal operation. If the concern is still present, REFER to: Catalyst System .
Burning smell -- usually occurs at idle, with possible traces of smoke	Foreign material trapped in exhaust system Missing heat shields	INSPECT the exhaust system for foreign material or missing heat shields. REPAIR or INSTALL new components as necessary.
Odor -- described as a sulfur or rotten egg smell	Catalytic converter Excessive sulfur content in fuel	At times, a slight sulfur smell is normal for catalytic converters. The cause is the sulfur content in the gasoline being used. ADVISE the customer no repair is required.
Odor -- described as a sulfur or rotten egg smell	Rich fuel conditions Misfire conditions	REFER to: Catalyst System . REFER to: Engine Ignition .
Visible rust on surface of exhaust pipes	Catalytic converter/exhaust system	Surface rust is a characteristic of the materials used for exhaust systems. Exposure to heat or road salt may result in surface rust. INSPECT for perforations. If there are no perforations, the condition is normal.

Symptom Chart: Symptom Chart - NVH

Symptom Chart

Condition	Possible Sources	Actions
Rattle, squeaks or buzz type noise -- from underneath the vehicle	Loose or damaged heat shield	INSPECT the exhaust system for loose or missing heat shields or foreign material trapped between the heat shields and the exhaust system components. If any heat shields are loose, INSTALL any required exhaust fasteners and TIGHTEN to specification. If the heat shields are missing, or a rattle, squeak or buzz condition persists, INSTALL a new heat shield or components as necessary.
	Loose or damaged exhaust isolator	VERIFY the exhaust isolators are correctly installed. INSPECT the exhaust isolators for wear or damage. INSTALL new isolators as necessary.
	Loose or damaged exhaust isolator hanger bracket	INSPECT the exhaust system components for damaged or broken hangers. INSTALL new components as necessary. CHECK for loose or damaged exhaust hanger brackets or fasteners. TIGHTEN the bolts to specification or INSTALL new components as necessary.
	Loose or damaged catalytic converter or muffler	MOVE the exhaust system to simulate the bouncing action of the vehicle, while checking for exhaust-to-body contact. Using a rubber mallet, TAP on the exhaust components to duplicate the noise concern. Lightly TAP on the muffler, then the catalytic converters. DETERMINE if there are loose or broken baffles in the muffler or a loose or broken element in the catalytic converters. REPAIR or INSTALL new components as necessary.
	Exhaust grounded to chassis	INSPECT for signs of exhaust components-to-body contact. REPAIR or INSTALL new components as necessary.
Drone or clunk type noise -- from underneath the vehicle	Loose or damaged exhaust isolator	VERIFY the exhaust isolators are correctly installed. INSPECT the exhaust isolators for wear or damage. INSTALL new isolators as necessary.
Drone or clunk type noise -- from underneath the vehicle	Exhaust grounded to chassis	INSPECT for signs of exhaust components-to-body contact. REPAIR or INSTALL new components as necessary.
Whistles, boom, hum or ticking type noise -- noise tends to change as the engine warms. The noises are often accompanied by exhaust fumes	Exhaust system leak	INSPECT the entire exhaust system for leaks. CHECK for punctures, loose or damaged clamps/fasteners, gaskets, sensors or broken welds. EXAMINE the chassis for grayish-white or black exhaust soot, which indicates exhaust leakage at that point. To magnify a small leak, with the aid of another technician, hold a suitable material over the tail pipe outlet to increase back pressure while listening for a leak. REPAIR or INSTALL new components as necessary.
	Loose or damaged catalytic converter or muffler	MOVE the exhaust system to simulate the bouncing action of the vehicle, while checking for exhaust-to-body contact. Using a rubber mallet, TAP on the exhaust components to duplicate the noise concern. Lightly TAP on the muffler, then the catalytic converters. DETERMINE if there are loose or broken baffles in the muffler or a loose or broken element in the catalytic converters. REPAIR or INSTALL new components as necessary.
	Exhaust muffler/resonator drain hole enlarged due to corrosion	CONFIRM the noise concern is caused by an enlarged drain hole due to corrosion. INSTALL new components as necessary.
Hissing or rushing noise -- high frequency sound. Vehicle performance is unaffected	Exhaust system flow through pipes	INSPECT the entire exhaust system for leaks. CHECK for punctures, loose or damaged clamps/fasteners, gaskets, sensors or broken welds. EXAMINE the chassis for grayish-white or black exhaust soot, which indicates exhaust leakage at that point. To magnify a small leak, with the aid of another technician, hold a suitable material over the tail pipe outlet to increase back pressure while listening for a leak. REPAIR or INSTALL new components as necessary.
Pinging noise -- occurs when exhaust system is hot, engine turned off	Catalytic converter/exhaust system	Cool down pinging is a result of the exhaust system components expanding and contracting during heating and cooling. This is a normal condition.
Vibration -- occurs at idle and at low speeds. Also accompanied by a clunk or buzz type noise	Loose or damaged exhaust isolator	VERIFY the exhaust isolators are correctly installed. INSPECT the exhaust isolators for wear or damage. INSTALL new isolators as necessary.
	Loose or damaged exhaust isolator hanger bracket	INSPECT the exhaust system components for damaged or broken hangers. INSTALL new components as necessary. CHECK for loose or damaged exhaust hanger brackets or fasteners. TIGHTEN the bolts to specification or INSTALL new components as necessary.
	Exhaust grounded to chassis	REPAIR or INSTALL new components as necessary.
Engine drumming noise -- normally accompanied by vibration	Damaged or misaligned exhaust system	CHECK the exhaust system to chassis clearance. INSPECT the exhaust system for loose or damaged fasteners, hanger brackets or isolators. REPAIR or INSTALL new components as necessary.
Sputter type noise -- noise worse when cold, lessens or disappears when the vehicle is at operating temperature	Damaged or worn exhaust system	INSPECT the exhaust system for leaks or damage. REPAIR as necessary.
Thumping noise -- from underneath the vehicle, worse during acceleration	Damaged or misaligned exhaust system	CHECK the exhaust system to chassis clearance. INSPECT the exhaust system for loose or damaged fasteners, hanger brackets or isolators. REPAIR or INSTALL new components as necessary.
Engine vibration -- is felt with increases and decreases in engine rpm	Strain on exhaust system isolators	REPAIR or INSTALL new components as necessary.
Drumming noise -- occurs inside the vehicle during idle or high idle, hot or cold. Very low-frequency drumming is very rpm dependent	Exhaust system vibration excites the body resonances inducing interior noise	REPAIR or INSTALL new components as necessary.