New check valve prevents fluid from backing up through the regulator. The most common cause of lh jetronic ecu failure is the hybrid control circuit. There are 4 variations of bosch lh jetronic on volvo 240 models. Signification des cas specifiques c o mposants et accessoires. If there is spark, then the ignition system is working, there is no need to test the engine rpm speed sensor or ezk output stage. While port injection systems such as ke and ljetronic employ a separate injector for each cylinder, monojetronic features a single, centrallylocated, solenoidcon. A thorough understanding of the various components is required before working on kjetronic fuel systems. Ke jetronic troubleshooting for most pre1991 manufactured w124s, the fuel injection system on these engines are mostly using bosch kejetronic. L jetronic principle with electronic mapcontrolled ignition.
The injection has as function to provide the amount of fuel exactly dosed. This adapter allows you to calibrate the bosch lhjetronic. Jetronic is a trade name of a fuel injection technology for automotive petrol engines, developed and marketed by robert bosch gmbh from the 1960s onwards. Use caution, the 928 spark system produces high voltage and can cause death or serious injury. The early jecs lh jetronic systems were based on a motorola.
Onsomeljetronic systems, the air temperature sen sor is visible in the air flow meter inlet. If the inlet air temperature sensor fails its resistance tests, you cant service just the sensor. Vw l jetronic fuel injection workshop manual author. The le jetronic command unit receives various input signals, from the various sensors that send precise information about the instant engine operation conditions. Though mostly mechanical in nature and lacking the feedback o2 sensor to correct the airfuel mixture, it was considered sufficient in providing the control of the injection of fuel back in the days. The lejetronic system is electronically commanded and injects the fuel in the intake manifold. Bosch licensed the concept to many automobile manufacturers. Monojetronic fuelinjection system system overview monojetronic is an electronically controlled, lowpressure, singlepoint injection spi system for 4cylinder engines. Before troubleshooting, testing or adjusting the kjetronic fuel injection system, the ignition system and the mechanical system of the engine compression, valve timing, etc. Read above, i explained that lh jetronic has 2 seperate controllers and motronic controlls them togeather.
There are several variations of the technology offering technological development and refinement. Vw l jetronic fuel injection workshop manual created date. New design reduces potential damage by separating the gauges and manifold from the canister during filling. Lele2lu a 010902021 9705 1 operation lele2lu jetronic foreword the multitester pluspro software cassette is the component that gives the diagnostic equipment its unique test characteristics. Vw ljetronic fuel injection workshop manual created date. How can i tell which version of bosch lh fuel injection is. With the engine running, touch a long shaft such as a screwdriver to the injector and listen to the opposite end. Then, the command unit processes this information received and calculate the appropriate fuel injection time, through an electric signal. Gregs bosch ljetronic fuel injection idle adjustment, diagnostic and tune up page, latest revision sept. Bosch le jetronic bmw copyright equiptech boschlejetronic thereismuchconfusionabouttheactualtypeofinjectionsystemfittedtomanybmwmotorcarsduringtheperiod1980to.
Gregs bosch l jetronic fuel injection idle adjustment, diagnostic and tune up page, latest revision sept. Ke jetronic troubleshooting for most pre1991 manufactured w124s, the fuel injection system on these engines are mostly using bosch ke jetronic. The charts are broken out by lh system version and catalyst or no catalyst. As stated in the video, you have access to all measures of the original software. There are two separate temperature sensors housed in the one sensor body in lh fuel injected 928s, one sensor is for the lh and the other for the spark module. B 230 f gasoline engine with fuel injection and cataly tic con erter system. This synthesis, comprising the mechanical basic functions coupled with electronic adap tation and opti mization functions, is the kejetronic. There is alot of information on high performance lh jetronic systems but the problem with the system as far as i know is its inability to measure large amounts of airflow without moddifications since it uses a total flow sensor as far as. New design reduces damage to the oring by limiting exposure to cleaning solution. Hookup the auxiliary fuel tank and fittings as shown on page 4. Jun 22, 2011 this adapter allows you to calibrate the bosch lh jetronic. Lh jetronic injection manifold1982 and later b21 and b23f lh models a quick way to check injectors is simply to listen to them. The ezk ignition module from the same car as the lhjet 572 the whole harness from the lhjet and exk modules into the engine bay. By club member john hall, who worked for volvo usa for many years.
It is a socalled hybrid a mixture of mechanical and electronic injection systems. While new carburated engines were used in the european markets, vw adapted the ljetronic for the type 4 in the us due to more stringent emissions and fuel consumption regulations. Jun 08, 2012 this video shows how to engineer modelbased functions for the lh jetronic 2. Anyhow here is the link bosch k jetronic fuel injection manual. While port injection systems such as ke and l jetronic employ a separate injector for each cylinder, mono jetronic features a single, centrallylocated, solenoidcon. The ezk ignition module from the same car as the lh jet 572 the whole harness from the lh jet and exk modules into the engine bay. Basically, it is pretty similar to the kjetronic with some changes and modifications. Interject kjetronic servicing and cleaning procedure 1.
Lhjetronic injection manifold1982 and later b21 and b23flh models a quick way to check injectors is simply to listen to them. Created on 20110617 by kevin rutledge, last updated on 20181112. Mono jetronic fuelinjection system system overview mono jetronic is an electronically controlled, lowpressure, singlepoint injection spi system for 4cylinder engines. Kjetronic system overview fuel supply 14 fuel metering 18 adapting to operating conditions 24 supplementary functions 30 exhaustgas treatment 32 electrical circuitry 36 workshop testing techniques 38 kjetronic since its introduction, the kjetronic gasolineinjection system has proved itself in millions of vehicles. How can i tell which version of bosch lh fuel injection is on. L jetronic system fuel injectors n open when energized by ecu not continuous as k jetronic. K jetronic system overview fuel supply 14 fuel metering 18 adapting to operating conditions 24 supplementary functions 30 exhaustgas treatment 32 electrical circuitry 36 workshop testing techniques 38 k jetronic since its introduction, the k jetronic gasolineinjection system has proved itself in millions of vehicles. This video shows how to engineer modelbased functions for the lhjetronic 2. Vw ljetronic fuel injection workshop manual author. Mar 27, 2006 read above, i explained that lh jetronic has 2 seperate controllers and motronic controlls them togeather. There are 4 variations of bosch lhjetronic on volvo 240 models. This chart is a summary of bosch lhjetronic components for the saab 900 and 9000 cars, from 1984 through 1994.
Disconnect the return line from the distributor head 6a, and connect a hose from the. There is alot of information on high performance lh jetronic systems but the problem with the system as far as i know is its inability to measure large amounts of airflow without moddifications since it uses a total flow sensor as far as my information says. Possibly the intake port need to disable and plug the cold start injector. The most common cause of lhjetronic ecu failure is. Ac switch system relay pressure regu lator fuel distribution. Bosch l jetronic l jetronic rx7 brought to you by the team at created date. This video shows how to engineer modelbased functions for the lh jetronic 2.
By the mid1980s, jecs were using lh jetronic, and the new bosch hotwire mass airflow meter. Onsomel jetronic systems, the air temperature sen sor is visible in the air flow meter inlet. Bosch l jetronic fuel injection troubleshooting, maintenance. Bosch ljetronic l jetronic rx7 brought to you by the team at created date.
A thorough understanding of the various components is required before working on k jetronic fuel systems. You can both modify parameterscurvesmaps and read out all internal values. Check the system pressure and flow with the lb2912f. Before troubleshooting, testing or adjusting the k jetronic fuel injection system, the ignition system and the mechanical system of the engine compression, valve timing, etc. Or lets have a look at one more version bosch cise continuous injection system electronic. The easiest way to tell is to look at the maf sensor. New design incorporates anodized bottle with permanent laser etching for a sleeker appearance. Anyhow here is the link bosch kjetronic fuel injection manual. Note the orientation of the protruding alignment notch. Ljetronic fuel injection technical troubleshooting article. Ljetronic the bosch ljetronic also called afcair flow controlled fuel injection was put into usspec type 4s in the last model year 1974. All data required to make the test system operate are stored on the software cassette. Ljetronic system air mass measurement n fuel injection system has to know mass of air n airflow meter provides air mass flow information u mass is calculated by volume flow and density f need device to determine flow air flap on airflow meter f need temperature to determine density temperature sensor in air flow meter afm 1 throttle plate 2 air flow. Air mass meter amm with aluminum body and adjustable mixture.