Bosch CIS generations (was: '86 CGT failing emissions..ideas? ...)

Ti Kan ti at
Tue Jul 31 03:02:11 EDT 2001

AllenDesignAtl at writes:
> This coupe GT sports the KE-Jetronic CIS system also known as K-Jetronic 
> with Lambda

Actually, that's not a technically accurate statement.  There are several
generations of Bosch CIS, as follows.  All CIS systems use a mechanical
fuel distributor with a conical air funnel and air sensor plate.  CIS systems
inject fuel "K"ontinuously.  Those with an ECU generally manage only fuel
quantity, except KE-Motronic and those with the Hitachi MAC-* ECUs.

Bosch name		VW/Audi name	Brief description
---------------------	--------------	----------------------
K-Jetronic		CIS		All mechanical
K-Jetronic w/ Lambda	CIS w/ Lambda	Mechanical w/ analog ECU, OXS, FV
					and CPR
KE-Jetronic		CIS-E		Mechanical w/ digital ECU, OXS and DPR
KE3-Jetronic		CIS-III		Similar to CIS-E but more advanced,
					separate fuel and ignition ECUs that
					"talk" to each other.
KE-Motronic		CIS-Motronic	Similar to CIS-E, single fuel and
					ignition management ECU

OXS = oxygen sensor
FV = frequency valve
CPR = control pressure regulator, mounted on block
DPR = differential pressure regulator, on fuel distributor body

K-Jetronic fuel distributor bodies are painted black whereas KE fuel
distributors are silver.

Audi's 5000/200 turbo cars use a variation of the K-Jetronic w/ Lambda,
incorporating a proprietary (Hitachi MAC-* series) ECU for combined fuel,
ignition and boost control.  All other Audis with CIS use one of the "standard"
setups as listed in the table above.

Pretty much all Audis changed to the "pulsed" electronic sequential fuel
injection with fuel rail and digital ECU for combined fuel/ignition (and
boost control if turbo) after around the 1991-92 time frame, first with
the 20V I5 cars, then the V6s and all later engines.  Most are Bosch
Motronic, but some (like the V6 2.8 12V) used a Hitachi-based system.

01 S4 2.7 biturbo quattro
84 5000S 2.1 turbo
80 4000 2.0
    ///  Ti Kan                Vorsprung durch Technik
   ///   AMB Research Laboratories, Sunnyvale, CA. USA
  ///    ti at

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