Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSSAAB19879000 L4-1985CC 2.0L DOHCREPAIR AND DIAGNOSISPOWERTRAIN MANAGEMENTCOMPUTERS AND CONTROL SYSTEMSDESCRIPTION AND OPERATIONFUNCTIONAL DESCRIPTIONLIMP HOME MODE
1987 Saab 9000 L4-1985cc 2.0L DOHC
Limp Home Mode
1987 Saab 9000 L4-1985cc 2.0L DOHCSECTION Limp Home Mode
Limp Home Mode
Description
In the event of component failure, a Limp Home function in the LH system will be activated which enables the car to be driven but with reduced performance.
In the event of a fault in the mass air flow sensor, no information will be available on which to calculate injector opening duration. The control module then resorts to two default opening duration settings, above or below 2,000 rpm.
In the event of fault in the temperature sensor or an open circuit in the electrical connection, the control module assumes a fixed default value, +45°C (+20°C for LH 2.2).
In the event of a fault in the idle air control valve it will open so that an engine speed of 1,200-1,500 rpm will be obtained (LH 2.4 and LH 2.4.1). In the LH 2.4.2 system the valve opens for an engine speed of 850 rpm.
Description
In the event of component failure, a Limp Home function in the LH system will be activated which enables the car to be driven but with reduced performance.
In the event of a fault in the mass air flow sensor, no information will be available on which to calculate injector opening duration. The control module then resorts to two default opening duration settings, above or below 2,000 rpm.
In the event of fault in the temperature sensor or an open circuit in the electrical connection, the control module assumes a fixed default value, +45°C (+20°C for LH 2.2).
In the event of a fault in the idle air control valve it will open so that an engine speed of 1,200-1,500 rpm will be obtained (LH 2.4 and LH 2.4.1). In the LH 2.4.2 system the valve opens for an engine speed of 850 rpm.
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.