Renix made automobile electronic ignitions, fuel-injection systems, electronic automatic transmission controls, and various engine sensors.
The term Renix also has a number of applications. In certain
carburetorA carburetor or carburettor is a device that blends air and fuel for an internal combustion engine. It was invented by Karl Benz before 1885 and patented in 1886...
equipped
RenaultRenault S.A. is a French automaker producing cars, vans, buses, tractors, and trucks. Due to its alliance with Nissan, it is currently the world's fourth largest automaker. Headquartered in Boulogne-Billancourt, Renault owns the Romanian automaker Automobile Dacia and the Korean automaker Renault...
and
VolvoThe Volvo Group is a Swedish supplier of commercial vehicles such as trucks, buses and construction equipment, drive systems for marine and industrial applications, aerospace components and financial services...
models, it provided an electronic ignition system, consisting of an
engine control unitAn engine control unit , also known as power-train control module , is a type of electronic control unit that determines the amount of fuel, ignition timing and other parameters an internal combustion engine needs to keep running...
(ECU) to replace the job of contact breaker points in the distributor.
Renix made automobile electronic ignitions, fuel-injection systems, electronic automatic transmission controls, and various engine sensors.
The term Renix also has a number of applications. In certain
carburetorA carburetor or carburettor is a device that blends air and fuel for an internal combustion engine. It was invented by Karl Benz before 1885 and patented in 1886...
equipped
RenaultRenault S.A. is a French automaker producing cars, vans, buses, tractors, and trucks. Due to its alliance with Nissan, it is currently the world's fourth largest automaker. Headquartered in Boulogne-Billancourt, Renault owns the Romanian automaker Automobile Dacia and the Korean automaker Renault...
and
VolvoThe Volvo Group is a Swedish supplier of commercial vehicles such as trucks, buses and construction equipment, drive systems for marine and industrial applications, aerospace components and financial services...
models, it provided an electronic ignition system, consisting of an
engine control unitAn engine control unit , also known as power-train control module , is a type of electronic control unit that determines the amount of fuel, ignition timing and other parameters an internal combustion engine needs to keep running...
(ECU) to replace the job of contact breaker points in the distributor. The system used an angle sensor and a number of fuel sensors to provide a maintenance-free ignition system.
Later, the name was synonymous with a form of fuel injection. In such an application, it consisted of an ECU and a number of sensors. It was first seen in engines produced by Renault (
Renault 21The Renault 21 is a large family car produced by French automaker Renault between 1986 and 1994. It was also sold in North America through American Motors dealers as the Renault Medallion and the Eagle Medallion....
,
25The Renault 25 is an executive car produced by the French automaker Renault from 1984 to 1991. During its time, the 25 was Renault's flagship, the most expensive, prestigious, and largest vehicle in the company's line-up. It placed second in the 1985 European Car of the Year contest...
, and
EspaceThe Renault Espace is a large MPV from French car-maker Renault. Generations 1-3 were sold under the Renault brand but manufactured by Matra. The current fourth generation model, which seats seven passengers, was designed and is built by Renault; the Renault Grand Espace is a long-wheelbase version...
) in 2.0 and 2.2 L capacities. It is better known in America for its application in the AMC 4.0 L (displacing 3960 cc or 242 cubic inches) straight-6 engines. Production began by
American MotorsAmerican Motors Corporation was an American automobile company formed by the 1954 merger of Nash-Kelvinator Corporation and Hudson Motor Car Company — at the time, it was the largest corporate merger in U.S. history....
(AMC) with the 1987
Jeep Cherokee (XJ)The Jeep Cherokee is a unibody compact SUV. It shared the name of the original full-size SJ model, but without a body-on-frame chassis, it actually set the stage for the modern SUV. Its innovative appearance and sales popularity spawned important imitators as other automakers began to notice that...
models. It was preceded by the
AMC Computerized Engine ControlThe Computerized Engine Control or CEC system was an engine management system designed and used by American Motors and Jeep from 1980-1990, on the AMC 258 engine....
, and followed by the Mopar MPI system.
Renix Electronique
Renix Electronique S.A., was established in 1981 as a
joint ventureA joint venture is an entity formed between two or more parties to undertake economic activity together. The parties agree to create a new entity by both contributing equity, and they then share in the revenues, expenses, and control of the enterprise...
by
RenaultRenault S.A. is a French automaker producing cars, vans, buses, tractors, and trucks. Due to its alliance with Nissan, it is currently the world's fourth largest automaker. Headquartered in Boulogne-Billancourt, Renault owns the Romanian automaker Automobile Dacia and the Korean automaker Renault...
with 51 percent interest and
BendixThe Bendix Corporation was an American manufacturing and engineering company which during various times in its 60 year existence made brake systems, aeronautical hydraulics, avionics, radios, televisions and computers, and which licensed its name for use on home washing machines.-History:Bendix was...
with 49% that was headquartered in
ToulouseToulouse is a city in southwest France on the banks of the River Garonne, 590 km away from Paris and half-way between the Atlantic Ocean and the Mediterranean Sea. With 1,102,882 inhabitants as of Jan...
. When Renault encountered financial troubles in 1985, it sold its interest in Renix to
Allied Corp.Allied Corporation was a major American company with operations in the aerospace, automotive, oil and gas industries. It evolved from the Allied Chemical and Dye Corporation....
, a major auto industry supplier and the new owner of Bendix.
Renault applications
The Renix system was used in the J series engines as fitted to the Renault 21 and Savanna/Nevada, the Renault 25, and the Renault Espace. It was a multi-point fuel injection system, as opposed to a single-point system, with a number of air, throttle and pinking sensors, and an advanced computer. Application of the system could first be seen in 1984, three years before its American debut. The Renix system pushed the power of the carburetor-fed 1995 cc engine from to . It could also be found in 2.2 L engines fitted to R21, 25 and Espace models.
AMC/Jeep applications
The Renix ECU has a powerful
microprocessorA microprocessor incorporates most or all of the functions of a central processing unit on a single integrated circuit . The first microprocessors emerged in the early 1970s and were used for electronic calculators, using binary-coded decimal arithmetic on 4-bit words...
that was advanced technology for its time. It also incorporates an
engine knockingKnocking in spark-ignition internal combustion engines occurs when combustion of the air/fuel mixture in the cylinder starts off correctly in response to ignition by the spark plug, but one or more pockets of air/fuel mixture explode outside the envelope of the normal combustion front...
sensor that allows the computer to know if
detonationDetonation is a process of combustion in which a supersonic shock wave is propagated through a fluid due to an energy release in a reaction zone. It is the more powerful of the two general classes of combustion, the other one being deflagration. In a detonation, the shock compresses the material...
is occurring, thus allowing the computer to make
adaptive controlAdaptive control involves modifying the control law used by a controller to cope with the fact that the parameters of the system being controlled are slowly time-varying or uncertain. For example, as an aircraft flies, its mass will slowly decrease as a result of fuel consumption; we need a...
by individual cylinder corrections to prevent pinging. The knock detection uses the signal from a wide bank
accelerometerAn accelerometer measures the acceleration it experiences relative to freefall.Single- and multi-axis models are available to detect magnitude and direction of the acceleration as a vector quantity, and can be used to sense orientation, vibration and shock...
mounted on the
cylinder headIn an internal combustion engine, the cylinder head sits above the cylinders and consists of a platform containing part of the combustion chamber and the location of the valves and spark plugs...
. Good signal to noise ratio is obtained primarily through angular discrimination.
The Renix system has more inputs than the later Mopar system and in some ways is more complex. Its knock sensor automatically tunes the spark advance curve to an optimum mix for each cylinder. Some Renix controlled engines will actually get better
fuel economyFuel usage in automobiles refers to the relationship between distance traveled by an automobile and the amount of fuel consumed. There are no quantities or units for fuel usage defined in the International Standard ISO 31 Quantities and Units, so the nationally-defined reciprocal quantities fuel...
using higher octane fuel.
The Renix computer was first used on 1986 2.5 L
AMC 2.5 L four-cylinder enginesThe American Motors Corporation straight-4 engine was used by a number of AMC, Jeep, and Dodge vehicles from 1984 through 2002.* For an outline of all engines used by AMC see -Development:...
s. The system improved the drivability of the Jeep Cherokee XJ models and the Comanche pickups over the first two months of production that were fitted with carburetors. The power increase was also noticeable. The Renix system was used through the 1990 model year. Unfortunately, the Renix system is now handicapped because there are few scan tools that can be "plugged in" to this
on-board diagnosticsOn-Board Diagnostics, or OBD, in an automotive context, is a generic term referring to a vehicle's self-diagnostic and reporting capability. OBD systems give the vehicle owner or a repair technician access to state of health information for various vehicle sub-systems...
computer.
History
Model years:
- 1986 - Renix TBI available on Jeep 2.5 L four-cylinder engines.
- 1987 - the new Renix controlled 4.0 L six-cylinder engine was rated at and ) of torque.
- 1988 - output increased to and of torque, due to higher compression ratio.
- 1989 - Changed to Renix MPFI.
- 1991 - Chrysler Corporation (then the owners of the Jeep brand replaced the Renix control system with OBD-I-compliant control electronics, the Chrysler HO EFI.
The Renix control system was only found on the 1987-1990 Jeep Cherokee and Comanche with AMC-designed engines (the control setup used with the
V6The General Motors 60° V6 family of engines began with the 1980 Chevrolet 2.8 L V6 and continues to be produced today . Its use in the X-body cars leads some to refer to it as the X engine.It is a 60° vee block with pushrod heads, except for a single DOHC member, the LQ1...
was OBD-I General Motors, and the early Diesel was a
RenaultRenault S.A. is a French automaker producing cars, vans, buses, tractors, and trucks. Due to its alliance with Nissan, it is currently the world's fourth largest automaker. Headquartered in Boulogne-Billancourt, Renault owns the Romanian automaker Automobile Dacia and the Korean automaker Renault...
turbodieselTurbodiesel refers to any diesel engine with a turbocharger. Turbocharging is the norm rather than the exception in modern car and truck diesel engines...
I4The inline-four engine or straight-four engine is a four-cylinder internal combustion engine with all four cylinders mounted in a straight line, or plane along the crankcase. The single bank of cylinders may be oriented in either a vertical or an inclined plane with all the pistons driving a...
that used its own specific control setup.) The CJ/YJ "Universal"
Jeep WranglerThe Wrangler is a compact four-wheel drive in the sport utility vehicle segment produced by American automaker Chrysler under its Jeep marque. It is a successor to the famous World War II 'Jeep' vehicle by way of the Willys civilian Jeep in the 1950s, later produced by Kaiser-Jeep and by American...
did not get the AMC 4.0 engine until 1991, when it was accompanied by Chrysler-designed electronics as well. Until then, it retained the AMC engine with a
carburetorA carburetor or carburettor is a device that blends air and fuel for an internal combustion engine. It was invented by Karl Benz before 1885 and patented in 1886...
. No other Jeep vehicle was equipped with Renix electronic controls.
Inspection stations
The Renix control system is "pre-OBD," and therefore does
not have a "Check Engine Lamp". It also does not "store" or "throw" Diagnostic Trouble Codes (DTCs) or "Parameter IDs" (PIDs) - see:
OBD-II PIDsP-codes, or OBD-II PIDs On Board Diagnostics "Parameter IDs", are codes used to request data from a vehicle, used as a diagnostic tool. These codes are part of SAE standard J/1979, required to be implemented in all cars sold in North America since 1996....
. This is a common problem at
vehicle inspectionVehicle inspection is a procedure mandated by national or subnational governments in many countries, in which a vehicle is inspected to ensure that it conforms to regulations governing safety, emissions, or both. Inspection can be required at various times, e.g., periodically or on transfer of...
, particularly in California and other jurisdictions with
emission standardEmissions standards are requirements that set specific limits to the amount of pollutants that can be released into the environment. Many emissions standards focus on regulating pollutants released by automobiles and other powered vehicles but they can also regulate emissions from industry, power...
s. Most inspection stations are not aware and will try to explain that the CEL/MIL "doesn't work" (note: there may be a cutout for it, but no bulb). It is recommended that the inspection technician be shown the "OBD Exempt" federal emissions label (located under the hood) and/or have the factory service manual as a reference to avoid this problem.
Volvo applications
The
Volvo 700 seriesThe Volvo 700 and 900 series are two ranges of mid-size car manufactured by Volvo Cars in the 1980s and 1990s. The 700 series was introduced in 1982, followed in 1990 by the 900 series...
used a B200K 2.0 L inline-4
naturally-aspirated engineA naturally-aspirated engine is a reciprocating internal combustion engine that depends solely on atmospheric pressure to draw in combustion air...
with Renix ignition.
See also
- AMC Straight-6 engine
The American Motors Corporation straight-6 family of engines was used by a number of AMC and Jeep vehicles from 1964 through 2006.* For an outline of all engines used by AMC see -195.6:American Motors' first straight-six engine was the...
- AMC Engines
The American Motors Corporation used V8, straight-6, V6, and straight-4 engines in various passenger automobiles and Jeep vehicles from 1964 through 2006. Some engines were of AMC design or inherited from its constituents...
- List of Chrysler engines
- Allpar's page