Hi! there ...
what kind of fuel inj. system this engines came with?..
I have this 82 242 with B23E , and i don't see any electric plugs for the injectors ..., not even a amm or O2 sensor ... but i know is fuel inj .


coper

Is it an automatic? It is my understanding (someone correct me if I am wrong) that the B23E with an automatic, configured with the head from a B21F and a vx cam is a pretty zippy engine. Of course, you would want to switch it over to a manual, but it is a configuration I wish I had in my 77.

--Joe HC
--
1977 244 160k (?), 1990 244 102k, 1978 Fiat 124 Spyder (restoring)

It is known as K-Jetronic because the German word for continuous is "Kontinuous", and the system is hydraulic in operation. Control pressure opposes the movement of the air flow sensor plate, and break pressures within the fuel distributor and injectors are also hydraulic in operation.
What makes the K-jet less than accurate is the method of determining mass air flow which is simply the "floating body" principle -the sensor plate, placed into a stepped orifice. Impact air lifts (or depresses) the sensor plate in relatively close correlation to the mass air flow. It is not as accurate as the L-jet swing gate, and certainly less accurate than the hot wire sensor of LH and Motronic. Nonetheless the K-jet is tough and reliable, depending on very little electrical (heaters and sensors) once fuel pressure is provided.
It's old, it's obsolete, but like the wonderful SU carburetor, it works really well......

K-Jetronic is a mechanical fuel injection.
--
'73 142, '75 242, '75 245, '80 245, '86 244, '87 745T

thanks evan.
are they any good compared with the computer managed jetronics ...?


coper .

K-jet is not "mechanical" in the sense of, for example, the old Bendix system of the 50's and 60's that rightfully earned a reputation for being unreliable, tempermental and very expensive to maintain. There is a control unit, but fewer electronic sensors (no air mass meter!), and fuel delivery is constant with the only variable being fuel pressure.

LH-Jet "pulses" the injectors on and off and can control the duration of each "pulse." You get a more precise mixture and thus better fuel economy as well as lower emissions with LH-Jet, but IME the trade off is reliability. Some of the most common running problems on LH-Jet cars are caused by failed air mass meters, crank position sensors, and electronic control units. These parts are expensive even when purchased remanufactured or used, and some (e.g. air mass meter) seem prone to fail every so many years/miles.

I have 230,000 on an '85 244Ti with K-Jet. Have only needed to replace the regulator, and the fuel filter as noted in the maintenance chart. Mileage with a manual tranny and heavy foot is about 20 in town, and 22-23 "on the road." Not bad considering the 3.73 gears and aforementioned lead foot. My LH-Jet '89 245 (157K,M47) gets only marginally better mileage - about 22 in town and 25, sometimes 26, on the highway. Have had to put two air mass meters in that car (removed the airbox t-stat after the first one died), and also the ECU ($$$).

Just to be nitpicker, kjet isn't technicaly a mechanical system- it works using fuel pressure, and fuel flow is constant- hence it is sometimes referred to as CIS- continuous injection system.

I like Kjet. It is very reliable. Most problems are with the control pressure regulator and the pumps.

You won't get as good fuel economy as you get with EFI. Yesterday I got 28.5 MPG on the highway- the best I ever got! Must have been a tail wind!!

Just to confuse the terminology issue a bit more, it's worth noting that CIS is also an acronym for the idle system on that same fuel system - constant idle system. So, the CIS (idle) control unit is situated directly below the CIS (K-jet) control unit.