1990 VOLKSWAGEN CORRADO mileage

COMPUTER RELEARN PROCEDURES
Article Text
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:43PM
ARTICLE BEGINNING
GENERAL INFORMATION
Computer Relearn Procedures
All Models
* PLEASE READ THIS FIRST *
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.
To reduce the possibility of complaints, after any service
which requires battery power to be disconnected, vehicle should be
road tested.
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. If a specific relearn
procedure is not available, the following procedure may be used:
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

E - THEORY/OPERATION - DIGIFANT
Article Text (p. 8)
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:43PMFig. 4: Identifying Evaporative Emissions System Components
Courtesy of Volkswagen United States, Inc.
SELF-DIAGNOSTIC SYSTEM
O2 SENSOR WARNING LIGHT
All vehicles are equipped with an O2 sensor warning light
located on the instrument panel. The light will illuminate when a
mileage counter reaches 60,000 miles (on Vanagon 90,000 miles)
indicating recommended O2 sensor replacement and mileage counter
reset.
CHECK ENGINE LIGHT (CALIF MODELS)
Some California vehicles are equipped with a CHECK engine
light and rocker switch on the instrument panel. The light will
illuminate when the ignition switch is turned to the ON position (for
bulb check) and when engine management systems are malfunctioning
during normal operation with the engine running. For additional
information see appropriate SELF-DIAGNOSTICS article.
MISCELLANEOUS CONTROLS
NOTE: Although not considered true Engine Performance related
systems, some controlled devices may affect driveability if
they malfunction.

EMISSION CONTROL VISUAL INSPECTION PROCEDURES
Article Text (p. 14)
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:44PMFig. 15: Typical Vacuum-Actuated EFE System
Courtesy of General Motors Corp.
EMISSION MAINTENANCE REMINDER LIGHT (EMR) (IF EQUIPPED)
If equipped, the EMR light (some models may use a reminder
flag) reminds vehicle operator that an emission system maintenance is
required. This indicator is activated after a predetermined
time/mileage.
When performing a smog check inspection, ensure EMR
indicator is not activated. On models using an EMR light, light should
glow when ignition switch is turned to ON position and should turn off
when engine is running.
If an EMR flag is present or an EMR light stays on with
engine running, fail vehicle and service or replace applicable
emission-related components. To reset an EMR indicator, refer to
appropriate MAINTENANCE REMINDER LIGHTS in the MAINTENANCE section.
MALFUNCTION INDICATOR LIGHT (MIL)
The Malfunction Indicator Light (MIL) is used to alert
vehicle operator that the computerized engine control system has
detected a malfunction (when it stays on all the time with engine
running). On some models, the MIL may also be used to display trouble
codes.
As a bulb and system check, malfunction indicator light will
glow when ignition switch is turned to ON position and engine is not
running. When engine is started, light should go out.

H - TESTS W/O CODES
Article Text
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:45PM
ARTICLE BEGINNING
1990 ENGINE PERFORMANCE
Trouble Shooting - No Codes
Volkswagen; Cabriolet, Corrado, Fox, Golf GL/GTI,
Jetta, Vanagon
INTRODUCTION
Before diagnosing symptoms or intermittent faults, perform
steps in F - BASIC TESTING article. Use this article to diagnose
driveability problems existing when a hard fault code is not present
or vehicle is not equipped with a self-diagnostic system.
NOTE: Some driveability problems may have been corrected by
manufacturer with a revised computer calibration chip or
computer control unit. Check with manufacturer for latest
chip or computer application.
Symptom checks can direct the technician to malfunctioning
component(s) for further diagnosis. A symptom should lead to a
specific component, system test or an adjustment.
Use intermittent test procedures to locate driveability
problems that DO NOT occur when the vehicle is being tested. These
test procedures should also be used if a soft (intermittent) trouble
code was present, but no problem was found during self-diagnostic
testing.
NOTE: For specific testing procedures, see I - SYSTEM/COMP
TESTS article. For specifications, see D - ADJUSTMENTS
or C - SPECIFICATIONS articles.
SYMPTOM DIAGNOSIS
Symptom checks cannot be used properly unless the problem is
actually happening while the vehicle is being tested. To reduce
diagnostic time, ensure steps in F - BASIC TESTING article have been
performed before attempting to diagnose a symptom. Symptoms available
for diagnosis include the following:
* Will Not Start or Starts Hard Cold (Cranks Okay)
* Will Not Start or Starts Hard Hot (Cranks Okay)
* Engine Stalls or Idles Rough
* Engine Misfires or Hesitates
* Excessive Fast Idle
* Engine Hesitates On Acceleration
* Engine Lacks Power
* Poor Fuel Mileage
* Engine Diesels
* Failed Emissions Test

H - TESTS W/O CODES
Article Text (p. 5)
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:45PM
* Ensure there are no vacuum leaks.
* Check idle stabilizer operation (if equipped).
* Ensure fuel system pressure and volume are correct.
* Check auxiliary air by-pass regulator.
* Check cold start valve for leaking (engine warm).
ENGINE HESITATES ON ACCELERATION
* Inspect intake air components for leaking hoses
* Check injector spray pattern. Check for faulty injectors.
* Check cold start valve for leaking (engine warm).
* Check airflow sensor plate movement. Replace fuel distributor
as necessary.
* Check airflow sensor plate position. Adjust as necessary.
* Check fuel system and control system pressure. Replace pressure
regulator if necessary.
* Test airflow sensor plate potentiometer. Adjust or replace
as necessary.
* Perform system electrical checks.
* Check idle mixture CO adjustment. Adjust as necessary.
ENGINE LACKS POWER
* Test coolant temperature sensor and wiring. Repair or
replace as required.
* Check fuel system and control system pressure. Replace pressure
regulator if necessary.
* Check throttle cable adjustment.
* Check throttle switch. Adjust or replace as necessary.
* Check airflow sensor screen for damage or incorrect installation
(if equipped).
* Check ignition timing and knock sensor control (if equipped).
Adjust as necessary.
* Check EGR system for correct operation (if equipped).
* Ensure base timing is correct and timing advance system
is functional.
* Check transmission for correct downshift (auto. trans.)
* Check fuel tank filler tube for tampering of restrictor. If
tampering has occurred, check catalytic converter for lead
contamination and exhaust system restriction.
* Check for use of poor quality fuel containing insufficient
cleaning additives. Prolonged use of poor quality fuel can
cause injector clogging and carbon build-up on intake system.
* Inspect intake air element, housing, and preheating system.
* Check airflow sensor plate movement. Replace if necessary.
POOR FUEL MILEAGE
* Ensure idle speed, base timing and timing advance are
set to specifications.
* Check cold start valve for leaking (engine warm).

INTERFERENCE VERIFICATION CHECK FOR OHC ENGINE
Article Text
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:46PM
ARTICLE BEGINNING
Maintenance & Service Information
1974-96 Volkswagen - Timing Belt Information
Cabrio, Cabriolet, Corrado, Dasher, Eurovan (Canadian), Fox,
Golf, Golf (Canadian), GTI, GTI (Canadian), Jetta, Jetta GLI,
Passat, Passat (Canadian), Pickup, Quantum, Rabbit, Scirocco,
Scirocco (Canadian), Transporter (Canadian), Vanagon
TIMING BELT INTERFERENCE VERIFICATION INFORMATION
TIMING BELT INTERFERENCE CAUTION
NOTE: CAMSHAFT DRIVE BELTS OR TIMING BELTS - The condition of
camshaft drive belts should always be checked on vehicles
which have more than 50,000 miles. Although some
manufacturers do not recommend replacement at a specified
mileage, others require it at 60,000-100,000 miles. A
camshaft drive belt failure may cause extensive damage to
internal engine components on most engines, although some
designs do not allow piston-to-valve contact. These designs
are often called "Free Wheeling". Many manufacturers changed
their maintenance and warranty schedules in the mid-1980's to
reflect timing belt inspection and/or replacement at
50,000-60,000 miles. Most service interval schedules shown in
this section reflect these changes. Belts or components
should be inspected and replaced if any of the following
conditions exist:
* Crack Or Tears In Belt Surface
* Missing, Damaged, Cracked Or Rounded Teeth
* Oil Contamination
* Damaged Or Faulty Tensioners
* Incorrect Tension Adjustment
TIMING BELT INTERFERENCE CHECK MENU
TIMING BELT INTERFERENCE VERIF. TABLE - PASSENGER CARS (1)ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ Replacement Interval
Application Engine (Miles)
Cabrio
1995-96 .......... 2.0L 4-Cyl. ............ (3) 60,000
Cabriolet
1985-89 ....... 1.8L 4-Cyl. (DOHC) ........ (3) 60,000
1.8L 4-Cyl. (SOHC) ........ (3) 60,000
1990-93 .......... 1.8L 4-Cyl. ............ (3) 60,000
Corrado
1990-92 .......... 1.8L 4-Cyl. ............ (3) 60,000
Dasher

MAINTENANCE INFORMATION
Article Text (p. 2)
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:48PM
5 - Engine
B * 1.8L 4-Cyl. G-60 Supercharged Digifant FI, 158 HP (1990-92)
D * 2.8L V6 Motronic M2.9 FI, 172 HP (1992-93)
F * 2.8L V6 Motronic SFI, 172 HP (1994)
6 - Restraint System
4 * Electric Passive With Manual Lap
7-8 - Model
50 * Corrado
9 - VIN Check Digit
2 * Computer Selected Check Number
10 - Vehicle Model Year
L * 1990
M * 1991
N * 1992
P * 1993
R * 1994
11 - Assembly Plant
A * Ingolstadt
B * Brussel
E * Emden
G * Graz
H * Hannover
K * Osnabruk
M * Mexico
N * Neckarsulm
P * Brazil
S * Stuttgart
W * Wolfsburg
12-17 - Serial Number
* Sequential Production Number
MAINTENANCE SERVICE INFORMATION
SEVERE & NORMAL SERVICE DEFINITIONS
NOTE: Use the Severe Service schedule if the vehicle to be serviced
is operated under ANY (one or more) of these conditions:
Service is recommended at mileage intervals based on vehicle
operation. Service schedules are based on the following primary
operating conditions:
Normal Service
* Driven More Than 10 Miles Daily
* No Operating Conditions From Severe Service Schedule

MAINTENANCE INFORMATION
Article Text (p. 3)
1990 Volkswagen Corrado
For Volkswagen Technical Site: http://vw.belcom.ru
Copyright © 1998 Mitchell Repair Information Company, LLC
Thursday, March 23, 2000 09:48PM
Severe Service (Unique Driving Conditions)
* Short Trips In Freezing Temperatures
* Towing Or Heavily Loaded
* Severe Dust Conditions
* Hot Weather, Stop-And-Go Driving
* Extensive Idling
CAMSHAFT TIMING BELT
CAUTION: Failure to replace a faulty camshaft timing belt may result
in serious engine damage.
The condition of camshaft drive belts should always be
checked on vehicles which have more than 50,000 miles. Although some
manufacturers do not recommend belt replacement at a specified
mileage, others require it at 60,000-100,000 miles. A camshaft drive
belt failure may cause extensive damage to internal engine components
on most engines, although some designs do not allow piston-to-valve
contact. These designs are often called "Free Wheeling".
Many manufacturers changed their maintenance and warranty
schedules in the mid-1980's to reflect timing belt inspection and/or
replacement at 50,000-60,000 miles. Most service interval schedules in
this manual reflect these changes.
Belts or components should be inspected and replaced if any
of the following conditions exist:
* Cracks Or Tears In Belt Surface
* Missing, Damaged, Cracked Or Rounded Teeth
* Oil Contamination
* Damaged Or Faulty Tensioners
* Incorrect Tension Adjustment
Inspect camshaft timing belt condition every 20,000 miles.
Replace belt as necessary.
DRIVE BELT ROUTINGFig. 1: Drive Belt Tensioner Adjustment (VR6)
Courtesy of Volkswagen United States, Inc.