Saab: 1987 Saab 900 4 cyl non-turbo, k jetronic, inline fuel pump
QuestionQUESTION: I am wondering if the cis k-jetronic is the fuel system on this vehicle. The inline fuel pump has push on round pins for electrical connection. Also, any idea what the working pressure and flow rate are for this pump? Is the Bosch
0580 254 933 a cis k-jetronic pump? Is a larger flow or higher pressure after market pump acceptable? Thank-you.
Sincerely, Frank
ANSWER: Frank:
The fuel injection on the 1987 900 non-turbo is the all electronic BOSCH LH 2.2 system, NOT the CIS K-Jetronic which was used on earlier SAABS.
The fuel pump for the LH 2.2 can put out a maximum of 87 psi, but the system regulates the working pressure to around 40-43 psi as a function of operating conditions. So, yes it is possible to use a pump delivering up the 87 psi safely, which most after market alternatives will satisfy.I do not have the specifications for the flow rate, but again, aftermarket pumps should be satisfactory in this regard.
Hope this helps,
Jerry
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QUESTION: I should have specified that the motor is an 8 valve 4 cylinder. Other information I have found searching the internet indicates the 4 cylinder 8 valve motor was maintained with cis k-jetronic fuel injection at least through 1988 and not upgraded to the LH system while the 16 valve and turbo were. Also, is it possible to know for sure if the Bosch 0580 254 933 fuel pump is a cis k-jetronic system pump? Thank-you.
Sincerely, Frank
AnswerFrank:
I'd forgotten that there were still a 'few' cis systems as late as 1987. Anyway. my info for the CIS system is that the fuel pump must provide a minimum of 750 cc in 30 seconds at 11.5 V. Operating pressure should be 4.5-5.2 BAR (65-75 psi)static. My official Bosch K Jetronic service manual does not show fuel pump No. 0580 254 933 for any vehicle at all; it is from 1982 so that may explain it. It does show the SAAB fuel pump as No. 580 254 978, however.
Hope this helps,
Jerry
