fuel type FORD FESTIVA 1991 Service Manual

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A - ENGINE/VIN ID
1991 ENGINE PERFORMANCE Ford/Mercury - Introduction
APPLICATION
MODEL COVERAGE
VIN DEFINITION
Numbers preceding the explanations in the legend below refer to the sequence of characters as listed on VIN identification label.
SAMPLE VIN
Digit #: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17.
(VIN) K N J P T O 6 H 9 L 6 1 0 0 0 0 0.
VIN Definition
1-3 - Indicates Nation of Origin.
4 - Indicates Restraint System.
5 - Indicates Carline Code.
6-7 - Indicates Body Type.
8 - Indicates Engine Type.
9 - Indicates Check Digit.
10 - Indicates Model Year.
11 - Indicates Assembly Plant.
12-17 - Vehicle Serial Number.
ENGINE CODE LOCATION

Fig. 1: Engine Code Location

Courtesy of FORD MOTOR CO.
MODEL YEAR VIN CODE APPLICATION
ModelBody CodeEng. Type (1) Eng. IDFuel Sys.Ign. Sys.
Capri011.6LZPFIMagnetic
Capri011.6L Turbo6 (2) PFIMagnetic
Festiva05, 06, 071.3LHPFIMagnetic
(1)See vehicle engine code label affixed to timing belt cover, See Fig. 1 .
(2)XR2 model W/intercooled turbo.
VIN CodeModel Year
L1990
M1991
Copyr ight 2009 Mit chell Repair Information Company, LLC. All Rights Reserved.
Article GUID: A00022694
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TUNE-UP TROUBLE SHOOTING - GAS ENGINE VEHICLES
BASIC SPARK PLUG TROUBLE SHOOTING CHARTS
Faulty solenoid switch, switch connections or relayCheck all wiring between
relay and solenoid or replace
relay or solenoid as necessary
Broken lead or loose soldered connectionsRepair wire or wire
connections as necessary
Solenoid Plunger Vibrates When Switch is Engaged
Weak batteryCharge or replace battery as
necessary
Solenoid contacts corrodedClean contacts or replace
solenoid
Faulty wiringCheck all wiring leading to
solenoid
Broken connections inside switch coverRepair connections or replace
solenoid
Open hold-in wireReplace solenoid
Low Current Draw
Worn brushes or weakReplace brushes or brush
springs as necessary
High Pitched Whine During Cranking Before Engine Fires but Engine Fires and Cranks Normally
Distance too great between starter pinion and flywheelAlign starter or check that
correct starter and flywheel
are being used
High Pitched Whine After Engine Fires With Key released. Engine Fires and Cranks Normally
Distance too small between starter pinion and flywheelFlywheel runout contributes
to the intermittent nature
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. T he purpose of this T rouble Shooting inform ation is to provide a list
of com m on causes to problem sym ptom s. For m odel-specific T rouble Shooting, refer to SUBJECT ,
DIAGNOST IC, or T EST ING articles available in the section(s) you are accessing.
CONDITION & POSSIBLE CAUSECORRECTION
Normal Spark Plug Condition
Light Tan or Gray depositsNo Action
Electrode not burned or fouledNo Action
Gap tolerance not changedNo Action
Cold Fouling or Carbon Deposits
Overrich air/fuel mixtureAdjust air/fuel mixture, see
ENGINE PERFORMANCE
section
Faulty chokeReplace choke assembly, see
ENGINE PERFORMANCE
section
Clogged air filterClean and/or replace air filter
Incorrect idle speed or dirty carburetorReset idle speed and/ or clean
carburetor
Faulty ignition wiresReplace ignition wiring
Prolonged operation at idleShut engine off during long
idle
Sticking valves or worn valve guide sealsCheck valve train
Wet Fouling or Oil Deposits
Worn rings and pistonsInstall new rings and pistons
Excessive cylinder wearRebore or replace block
Excessive valve guide clearanceWorn or loose bearing
Gap Bridged
Deposits in combustion chamber becoming fused to electrodeClean combustion chamber of
deposits
Blistered Electrode
Engine overheatingCheck cooling system
Wrong type of fuelReplace with correct fuel
Loose spark plugsRetighten spark plugs
Over-advanced ignition timingReset ignition timing see
ENGINE PERFORMANCE
Pre-Ignition or Melted Electrodes
Incorrect type of fuelReplace with correct fuel
Incorrect ignition timingReset ignition timing see
ENGINE PERFORMANCE
Burned valvesReplace valves
Engine OverheatingCheck cooling system
Wrong type of spark plug, too hotReplace with correct spark
Page 21 of 36 MITCHELL 1 ARTICLE - GENERAL INFORMATION Trouble Shooting - Basic Procedures
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GENERAL INFORMATION
Com puter Relearn Procedures
COMPUTER RELEARN PROCEDURES
Vehicles equipped with engine or transmission computers may require a relearn procedure after vehicle battery is disconnected. Many vehicle
computers memorize and store vehicle operation patterns for optimum driveability and performance. When vehicle battery is disconnected,
this memory is lost. The computer will use default data until new data from each key start is stored. As computer memorizes vehicle operation
for each new key start, driveability is restored. Vehicle computers may memorize vehicles operation patterns for 40 of more key starts.
Customers often complain of driveability problems during relearn stage because vehicle acts differently then before being serviced. Depending
on type and make of vehicle and how it is equipped, the following complaints (driveability problems) may exist:
Harsh Or Poor Shift Quality
Rough Or Unstable Idle
Hesitation Or Stumble
Rich Or Lean Running
Poor Fuel Mileage
These symptoms and complaints should disappear after a number of drive cycles have been memorized. To reduce the possibility of
complaints, after any service which requires battery power to be disconnected, vehicle should be road tested.
GENERIC COMPUTER RELEARN PROCEDURES
Some manufacturers identify a specific relearn procedure which will help establish suitable driveability during relearn stage. These procedures
are especially important if vehicle is equipped with and electronically controlled automatic transmission or transaxle. Always complete
procedure before returning vehicle to customer. The following general procedures are to be used if driveability problems are encountered after
power loss or battery has been disconnected. These procedures may provide an aid in eliminating these problems.
Automatic Transmission
Set parking brake, start engine in "P" or "N" position. Warm-up vehicle to normal operating temperature or until cooling fan cycles.
Allow vehicle to idle for one minute in "N" position. Select "D" and allow engine to idle for one minute.
Accelerate at normal throttle position (20-50%) until vehicle shifts into top gear.
Cruise at light to medium throttle.
Decelerate to a stop, allowing vehicle to downshift, and use brakes normally.
Process may be repeated as necessary.
Manual Transmission
Place transmission in Neutral position.
Ensure emergency brake has been set and all accessories are turned off.
Start engine and bring to normal operating temperature.
Allow vehicle to idle in Neutral for one minute.
Initial relearn is complete, and process will be completed during normal driving.
Copyr ight 2009 Mitchell Repair Information Company, LLC. All Rights Reserved.
Article GUID: A00012612
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Fig. 7: Typical Thermostatic Air Cleaner System

FUEL EVAPORATIVE SYSTEM (EVAP)
The EVAP system allows for proper fuel system ventilation while preventing fuel vapors from reaching the atmosphere. This means that vapors
must be caught and stored while the engine is off, which is when most fuel evaporation occurs. When the engine is started, these fuel vapors
can be removed from storage and burned. In most systems, storage is provided by an activated charcoal (or carbon) canister. See Fig. 8
. On a
few early systems, charcoal canisters are not used. Instead, fuel vapors are vented into the PCV system and stored inside the crankcase.
The main components of a fuel evaporation system are a sealed fuel tank, a liquid-vapor separator and vent lines to a vapor-storing canister
filled with activated charcoal. The filler cap is normally not vented to the atmosphere, but is fitted with a valve to allow both pressure and
vacuum relief.
Although a few variations do exist between manufacturers, basic operation is the same for all systems. Check for presence of vapor storage
canister or crankcase storage connections when required. Ensure required hoses, solenoids, etc., are present and connected properly. Check
for proper type fuel tank cap. Check for any non-OEM or auxiliary fuel tanks for compliance and the required number of evaporation
canisters.

Fig. 8: Typical Fuel Evaporative System

CATALYTIC CONVERTERS
Oxidation Catalyst (OC)
This type of converter is the most common. It may use pellets or monolith medium, depending upon application. See Fig. 9 . Platinum and
palladium (or platinum alone) are used as catalyst in this type of converter.
Visually check for presence of catalytic converter(s). Check for external damage such as severe dents, removed or damaged heat shields, etc.
Also check for pellets or pieces of converter in the tailpipe.
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Fig. 9: Typical Oxidation Catalytic Converter (Pellet Type) Shown; Typical Three
-Way Catalytic Converter Is Similar
Courtesy of GENERAL MOTORS CORP.
Three-Way Catalyst (TWC)
This type of converter is nearly identical to a conventional converter with the exception of the catalyst. See Fig. 9 . The TWC converter uses
rhodium, with or without platinum, as its catalyst. Rhodium helps reduce NOx emissions, as well as HC and CO.
Visually check for presence of catalytic converter(s). Also check for presence of any required air supply system for the oxidizing section of the
converter. Check for external damage such as severe dents, removed or damaged heat shields, etc. Check for pellets or pieces of converter in
the tailpipe.
Three-Way Catalyst + Oxidation Catalyst (TWC + OC)
This system contains a TWC converter and an OC converter in a common housing, separated by a small air space. See Fig. 10. The 2 catalysts
are referred to as catalyst beds. Exhaust gases pass through the TWC first. The TWC bed performs the same function as it would as a separate
device, reducing all 3 emissions. As exhaust gases leave the bed, they pass through the air space and into the second (OC) converter catalyst
bed.
Visually check for presence of catalytic converter(s). Check for external damage such as severe dents, removed or damaged heat shields, etc.
Check for pellets or pieces of converter in the tailpipe.

Fig. 10: Typical Three
-Way + Oxidation Catalytic Converter
Courtesy of GENERAL MOTORS CORP.
FILL PIPE RESTRICTOR (FR)
A fuel tank fill pipe restrictor is used to prohibit the introduction of leaded fuel into the fuel tank. Unleaded gasoline pump dispensers have a
smaller diameter nozzle to fit fuel tank of vehicle requiring the use of unleaded fuel (vehicles equipped with catalytic converter).
Visually inspect fill pipe restrictor(s) for tampering, i.e., restrictor is oversize or the flapper is non-functional. If vehicle is equipped with an
auxiliary fuel tank, ensure auxiliary fuel tank is also equipped with a fill pipe restrictor.
EXHAUST GAS RECIRCULATION (EGR) SYSTEM
Single Diaphragm EGR Valve
This type uses a single diaphragm connected to the valve by a shaft. Diaphragm is spring-loaded to keep valve closed in the absence of
vacuum. As throttle valves open and engine speed increases, vacuum is applied to the EGR vacuum diaphragm, opening the EGR valve. This
vacuum signal comes from a ported vacuum source. Variations in the vacuum signal control the amount of exhaust gas that is recirculated. See
Fig. 11
.
Verify EGR valve is present and not modified or purposely damaged. Ensure thermal vacuum switches, pressure transducers, speed switches,
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Fig. 16: Cutaway View Of Typical Integrated Electronic EGR Valve

Courtesy of GENERAL MOTORS CORP.
SPARK CONTROLS (SPK)
Spark control systems are designed to ensure the air/fuel mixture is ignited at the best possible moment to provide optimum efficiency and
power and cleaner emissions.
Ensure vacuum hoses to the distributor, carburetor, spark delay valves, thermal vacuum switches, etc., are in place and routed properly. On
Computerized Engine Controls (CEC), check for presence of required sensors (O2, MAP, CTS, TPS, etc.). Ensure they have not been
tampered with or modified.
Check for visible modification or replacement of the feedback carburetor, fuel injection unit or injector(s) with a non-feedback carburetor or
fuel injection system. Check for modified emission-related components unacceptable for use on pollution-controlled vehicles.
AIR INJECTION SYSTEM (AIS)
Air Pump Injection System (AP)
The air pump is a belt-driven vane type pump, mounted to engine in combination with other accessories. The air pump itself consists of the
pump housing, an inner air cavity, a rotor and a vane assembly. As the vanes turn in the housing, filtered air is drawn in through the intake port
and pushed out through the exhaust port. See Fig. 17
.
Check for missing or disconnected belt, check valve(s), diverter valve(s), air distribution manifolds, etc. Check air injection system for proper
hose routing.
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Fig. 17: Typical Air Pump Injection System

Courtesy of GENERAL MOTORS CORP.
Pulsed Secondary Air Injection (PAIR) System
PAIR eliminates the need for an air pump and most of the associated hardware. Most systems consists of air delivery pipe(s), pulse valve(s) and
check valve(s). The check valve prevents exhaust gases from entering the air injection system. See Fig. 18
.
Ensure required check valve(s), diverter valve(s), air distribution manifolds, etc., are present. Check air injection system for proper hose
routing.

Fig. 18: Typical Pulsed Secondary Air Injection System

Courtesy of GENERAL MOTORS CORP.
OXYGEN SENSOR (O2)
The O2 sensor is mounted in the exhaust system where it monitors oxygen content of exhaust gases. Some vehicles may use 2 O2 sensors. The
O2 sensor produces a voltage signal which is proportional to exhaust gas oxygen concentration (0-3%) compared to outside oxygen (20-21%).
This voltage signal is low (about .1 volt) when a lean mixture is present and high (1.0 volt) when a rich mixture is present.
As ECM compensates for a lean or rich condition, this voltage signal constantly fluctuates between high and low, crossing a reference voltage
supplied by the ECM on the O2 signal line. This is referred to as cross counts. A problem in the O2 sensor circuit should set a related trouble
code.
COMPUTERIZED ENGINE CONTROLS (CEC)
The CEC system monitors and controls a variety of engine/vehicle functions. The CEC system is primarily an emission control system designed
to maintain a 14.7:1 air/fuel ratio under most operating conditions. When the ideal air/fuel ratio is maintained, the catalytic converter can
control oxides of nitrogen (NOx), hydrocarbon (HC) and carbon monoxide (CO) emissions.
The CEC system consists of the following sub-systems: Electronic Control Module (ECM), input devices (sensors and switches) and output
signals.
EARLY FUEL EVAPORATION (EFE)
The EFE valve is actuated by either a vacuum actuator or a bimetal spring (heat-riser type). The EFE valve is closed when engine is cold. The
closed valve restricts exhaust gas flow from the exhaust manifold. This forces part of the exhaust gas to flow up through a passage below the
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GENERAL INFORMATION
How To Use The Engine Perform ance Section - 1989 & Newer Models
* PLEASE READ THIS FIRST *
HOW TO USE THE ENGINE PERFORMANCE SECTION
Congratulations, you have purchased the most advanced automotive repair and service information available. This information can help you, as
a professional automotive technician, to maintain top vehicle performance, and correct driveability problems on today's high-tech vehicles.
For your convenience and ease in use, all of our engine performance service and repair information is consistently organized by manufacturer,
using a progressive diagnostic/workflow approach. Due to the differences in how each manufacturer approaches diagnosis and repair, once
started and inside of an article, that manufacturer may drive the workflow in a direction other than what is outlined here.
The progressive diagnostic/workflow of our data is as follows:
APPLICATION to identify vehicle and system usage.
EMISSION APPLICATION to identify emission system usage.
SPECIFICATIONS to quickly find an engine performance service specification.
ADJUSTMENTS to perform engine performance related routine adjustments.
THEORY & OPERATION to familiarize yourself with new systems and technologies.
BASIC DIAGNOSTIC PROCEDURES located under TESTING & DIAGNOSTICS, also referred to as BASIC TESTING, is used for
performing a basic vehicle inspection and is also the starting point for diagnosis of a "no-start" condition.
SELF-DIAGNOSTICS located under TESTING & DIAGNOSTICS, also referred to as TESTS W/CODES, is where manufacturer
specific procedures for retrieving, identifying and diagnosing DTCs (trouble codes) retained in a control modules memory are located.
TROUBLE SHOOTING - NO CODES located under TESTING & DIAGNOSTICS, also referred to as TESTS W/O CODES, is where
an engine performance problem that does not set a DTC can be potentially isolated through either a SYMPTOM or INTERMITTENTS
duplication procedure.
SYSTEM & COMPONENT TESTING located under TESTING & DIAGNOSTICS, also referred to as SYSTEM/COMPONENT
TESTS, once directed to this article, specific system and component tests can be performed to help isolate faulty component/system
prior to replacement.
PIN VOLTAGE CHARTS provide supplemental information to help determine correct control module input and output signals. Pin
charts may also be referred to as PID charts by some manufacturers.
SENSOR RANGE CHARTS help determine if a sensor is out of calibration. In some cases an out-of-calibration sensor will not set a
DTC (trouble code), resulting in difficult to diagnose driveability symptoms.
VACUUM DIAGRAMS help determine correct routing of vacuum hoses when reinstalling components or performing emission
inspections.
REMOVE, OVERHAUL & INSTALL provides procedures necessary for removing and installing engine performance related
components.
WIRING DIAGRAMS can be used to identify circuits, terminals, wire colors and components referenced in testing procedures. NEW
COLOR WIRING DIAGRAMS (system diagrams) provide an easy method of identifying and tracing circuits.
APPLICATION
INTRODUCTION/ENGINE/VIN ID
Here you will find out how to identify an engine by its Vehicle Identification Number (VIN). The manufacturer's MODEL COVERAGE chart
lists each model and engine option, the fuel system, ignition system and engine code. Engine serial number locations are also shown here, as
well as the VIN code breakdown. Using model lookup in conjunction with VIN and engine ID will identify application information necessary
for servicing vehicle and ordering parts.
EMISSION APPLICATIONS
EMISSION APPLICATION TABLES
Here you will find a chart listing what emission control devices apply to each model. This can be helpful when performing government-
required emissions inspections. For quick reference, major emission systems and devices are listed in bold type in the emission table. Sub
components are listed in light type.
SPECIFICATIONS
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
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SERVICE & ADJUSTMENT SPECIFICATIONS
If you want a specification quickly, this is the place to look. Instead of hunting through a long article, we've separated out the important
specifications and arranged them into easy-to-use tables in a centralized location. You can find valuable information like spark plug wire
resistance, valve clearance, timing, firing orders, etc.
ADJUSTMENT
ON-VEHICLE ADJUSTMENTS
The ON-VEHICLE ADJUSTMENTS article contains the type of information that was previously thought of as TUNE-UP information.
Procedures for checking and adjusting valves, base ignition timing and idle speed are found in this section. Use this section in conjunction with
SERVICE & ADJUSTMENT SPECIFICATIONS for performing routine maintenance. Also, if you have a driveability problem, ensure all on-
vehicle adjustments are within specification before attempting further diagnosis.
THEORY & OPERATION
This article covers basic THEORY & OPERATION of engine performance-related systems and components. Before diagnosing vehicles or new
systems with which you are not completely familiar, read this article.
TESTING & DIAGNOSTICS
BASIC DIAGNOSTIC PROCEDURES/BASIC TESTING
The procedures listed in this article can help you avoid skipping a simple step early, like checking base timing, which could be costly in both
time and money later. This is also a potential starting point for diagnosis of a "no-start" condition. If all systems check out okay here, proceed
to SELF-DIAGNOSTICS/TESTS W/CODES or TROUBLE SHOOTING - NO CODES/TESTS W/O CODES article.
SELF-DIAGNOSTICS/TESTS W/CODES
Use this information to retrieve and interpret Diagnostic Trouble Codes (DTCs) accessed from the vehicle's self-diagnostic system. Once
information is retrieved, manufacturer diagnostic procedures are given to help pinpoint and repair computer system/component faults. Also
included are steps for clearing trouble codes once these faults are repaired. If there is a driveability symptom with no trouble codes set,
proceed to TROUBLE SHOOTING - NO CODES/TESTS W/O CODES article.
TROUBLE SHOOTING - NO CODES/TESTS W/O CODES
This is where to go when you have a problem that does not set a trouble code. It can help determine cause of problem using driveability
symptoms and intermittent testing procedures. Procedures in this information should lead you to a specific component or system test.
SYSTEM & COMPONENT TESTING
Here you will find various tests for engine performance systems and their components, such as air induction (turbochargers and superchargers),
fuel control, ignition control and emission systems.
PIN VOLTAGE CHARTS
These are supplied (when available from manufacturer) to quicken the diagnostic process. By checking pin voltages at the Powertrain Control
Module (PCM), you can determine if the PCM is receiving and/or transmitting proper voltage signals. Pin charts may also be referred to as PID
charts by some manufacturers.
SENSOR RANGE CHARTS
SENSOR OPERATING RANGE CHARTS
These are supplied (when available from manufacturer) to determine if a sensor is out of calibration. An out-of-calibration sensor may not set a
trouble code, but it may cause driveability problems.
VACUUM DIAGRAMS
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
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GENERAL INFORMATION
Waveform s - Injector Pattern T utorial
* PLEASE READ THIS FIRST *
PURPOSE OF THIS ARTICLE
Learning how to interpret injector drive patterns from a Lab Scope can be like learning ignition patterns all over again. This article exists to
ease you into becoming a skilled injector pattern interpreter.
You will learn:
How a DVOM and noid light fall short of a lab scope.
The two types of injector driver circuits, voltage controlled & current controlled.
The two ways injector circuits can be wired, constant ground/switched power & constant power/switched ground.
The two different pattern types you can use to diagnose with, voltage & current.
All the valuable details injector patterns can reveal.
SCOPE OF THIS ARTICLE
This is NOT a manufacturer specific article. All different types of systems are covered here, regardless of the specific year/make/model/engine.
The reason for such broad coverage is because there are only a few basic ways to operate a solenoid-type injector. By understanding the
fundamental principles, you will understand all the major points of injector patterns you encounter. Of course there are minor differences in
each specific system, but that is where a waveform library helps out.
If this is confusing, consider a secondary ignition pattern. Even though there are many different implementations, each still has a primary
voltage turn-on, firing line, spark line, etc.
If specific waveforms are available in On Demand for the engine and vehicle you are working on, you will find them in the Engine Performance
section under the Engine Performance category.
IS A LAB SCOPE NECESSARY?
INTRODUCTION
You probably have several tools at your disposal to diagnose injector circuits. But you might have questioned "Is a lab scope necessary to do a
thorough job, or will a set of noid lights and a multifunction DVOM do just as well?"
In the following text, we are going to look at what noid lights and DVOMs do best, do not do very well, and when they can mislead you. As
you might suspect, the lab scope, with its ability to look inside an active circuit, comes to the rescue by answering for the deficiencies of these
other tools.
OVERVIEW OF NOID LIGHT
The noid light is an excellent "quick and dirty" tool. It can usually be hooked to a fuel injector harness fast and the flashing l igh t is e a sy t o
understand. It is a dependable way to identify a no-pulse situation.
However, a noid light can be very deceptive in two cases:
If the wrong one is used for the circuit being tested. Beware: Just because a connector on a noid light fits the harness does not mean it is
the right one.
If an injector driver is weak or a minor voltage drop is present.
Use the Right Noid Light
In the following text we will look at what can happen if the wrong noid light is used, why there are different types of noid lights (besides
differences with connectors), how to identify the types of noid lights, and how to know the right type to use.
First, let's discuss what can happen if the incorrect type of noid light is used. You might see:
A dimly flashing light when it should be normal.
A normal flashing light when it should be dim.
A noid light will flash dim if used on a lower voltage circuit than it was designed for. A normally operating circuit would appear
underpowered, which could be misinterpreted as the cause of a fuel starvation problem.
Here are the two circuit types that could cause this problem: NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. For m odel-specific inform ation see appropriate articles where
available.
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. For m odel-specific inform ation see appropriate articles where
available.
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