Characteristics Of Lh2.4 Fuel System - Volvo 240 1989 Service Manual

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Design and function
Fuel system LH2.4 - 240
Characteristics of LH2.4 fuel system for Volvo 240:
It is used together with the EZ116K ignition sys­
tem.
It is an adaptive system. being capable of multiple
adjustments based on driving experience .
It is monitored
by a self-diagnostic system that
lights up a warning lamp on the instrument panel.
It has a memory capability of up to three fault
codes (Scandinavia/USA Federal ) plus seven ­
teen additional codes (USA/California). Subse­
quent fault tracing can be carried out by actively
utilizing the diagnostic program.
It measures intake air mass via air mass meter
supplied with a hot wire.
It utilizes a primary pump in the fuel tank and a fuel
pump with fuel filter on the fuel line to the engine .
II works on a fuel pressure of 300 kPa (42 psi) .
It
utilizes a separate cold slart valve which sup­
plies extra fuel at. or below 15°C (60"F) or cotder.
It provides a richer fuel mixture to counteract
knock when the fuel system's anti-knock control
system has been unsuccesslul at reducing knock
by adjusting downward several degrees .
It requires no adjustment of CO because of the
adaptive function.
It has a "limp home" se Ming at the idle valve In
case ofloss of current. the idle valve rem ain s open
to provide emergency air intake.
In the USA:
It has
an integrated shift Indicator
refated to vehicle speed and engine rpm. The
indicator famp lights up
if
the rpm for the next gear
are higher than the pre-programmed limits.
- It
uses an induction sensor on the flywheet to
indicate rpm and crankshaft position via the igni­
tion system control unit.
It is fitted with the same model Lambda-so nd as
for previous
l H
fuel systems. The resistance of
the Lambd a-sond is affected
by
the eXhaust-gasl
oxygen concentration The Lambda-sond is
mounted on the exhaust manifold between tile
engine and Ihe catalytic conver1er.
It is fi
tted
WIth a three-way catalylJc conver1er .
It utilizes an EVAP system to handle fuel vapors
in the fuel tank .
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