Manual for late 308 QV K-Jetronic?

Your '84-'85 US F V8 system is most commonly referred to as "K-Jetronic with Lambda" or "K-Lambda" (and, hydraulically, is the most complicated of all the Bosch CIS systems IMO ). Unfortunately, I haven't come across any F literature on that subject (if someone has -- please post title/info), but this Volvo link has some K-Lambda information in Part 3:

http://www.volvoclub.org.uk/tech/fuel_injection/k_jetronic.shtml

The best references that I've come across for your system are the Forbes Aird book - Bosch Fuel Injection Systems (which is sort of basic and easier to understand than the Probst book, so it makes a good starting point), and the Charles O. Probst book - Bosch Fuel Injection & Engine Management (which is more techy).

In almost all cases, the explanation strategy is to first explain K-Jetronic without Lambda to get the basics, then go into the differences for K-Jetronic with Lambda (or KE-Jetronic with Lambda or KE-Jetronic without Lambda).

To answer your specific question, the frequency valve (aka metering valve) is a "controlled leak" path from the lower chambers in the fuel distributor back to the fuel tank (controlled by the injection ECU based on the O2 sensor signal) -- i.e.:

If the O2 sensor reports a low voltage (lean) = the injection ECU increases the duty cycle to the FV = FV more (often) open = lowers the lower chamber pressure = lowers the upper chamber pressure = increases the pressure drop across the slits = more fuel delivered for same size slit opening = add richness

If the O2 sensor reports a high voltage (rich) = the injection ECU decreases the duty cycle to the FV = FV more (often) closed = raises the lower chamber pressure = raises the upper chamber pressure = decreases the pressure drop across the slits = less fuel delivered for same size slit opening = more lean

 

Yes on both items.

 

I haven't seen the other but the Probst book is excellent. I had never owned a car with Bosch FI and went from no knowledge at all to comfortably working on my 328's KJet using that book.

 

I bought one of these manuals:

http://cgi.ebay.com/ebaymotors/Ferrari-Mondial-328-Jetronic-Book-injection-System-/110574535753?pt=Motors_Manuals_Literature&hash=item19bec18449#ht_500wt_956

It's an actual printed original Ferrari manual not a pdf file. Surprisingly it's pretty inexpensive.

 

I didn't mean to imply that the Probst book is incomprehensible. If you are a complete novice, I'd recommend getting the Aird book, and then moving on to the Probst book, If you already have a some background in fuel delivery systems, going straight to the Probst book as Mike suggested, is fine.

 

I know the problem you are having with the manuals only showing the early system. Use Mercedes 380 manual and it will cover most of the functions of your system. If you go to my website and email a request for the info you want I can send you a bunch of files in pdf.

Larry Fletcher

www.cisflowtech.com

 

FWIW, Larry is awesome!!! He sent me a bunch of files recently as well when I got a rebuilt WUR from him.

Thanks again Larry and its great to see you here.



PDG


PS: @DWPC - What is the chassis of your car? Mine is 58027 and is also a May 85 build date.

 

I went through the manual it has pics of 328 engine. The back this printed "Cat. 539 / 89"

 

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