Rebuilt CIS Fuel Distributor?
02-06-2002, 11:14 AM
#16
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Location: Gautier Ms
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To Dennis and RandyV, How do you check pressures. I seem to have put the cart before the horse and bought the CIS gauge. Not quite sure where to plug into and get readings. My 78 has 117,000 miles and at least for the 11 years I have owned it this has not been checked. None of the books I have are pointing the way.
Down here in Mississippi I own "one of them foriegn cars"
Down here in Mississippi I own "one of them foriegn cars"
02-06-2002, 10:55 PM
#17
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Joe, while the CIS system (K-Jetronic) is inherently simple, testing for operating pressure isn't as easy as it is on the L-Jetronic.
In addition to the pressure guage, you will need a 3-position valve and a couple of adaptors.
The procedure is fairly extensive, covering 11 pages in the shop manual, versus 1 page for the L-Jetronic.
In addition to the pressure guage, you will need a 3-position valve and a couple of adaptors.
The procedure is fairly extensive, covering 11 pages in the shop manual, versus 1 page for the L-Jetronic.
02-06-2002, 11:09 PM
#18
Mississippi,
There are some good manuals on checking the fuel injections systems at your local auto parts store. I use the factory manuals and the Haynes fuel injection Techbook. If you get one make sure it includes the CIS system. Basically the tests are made on the system pressure and the control pressure. System pressure is normally measured between the center port of the fuel distributor and the outlet of the control pressure regulator (WUR) with the gauge valve closed. Control pressure is measured at the same location but with the valve open. Make sure the valve is on the fuel distributor side of the valve. The correct readings are very engine and temperature specific. Basically system pressure is between 65 and 85 psi. Control pressure should be between 14 and 35 psi depending upon temperature. The gauge setup and valve positions are very specific when testing the CIS. The last check is for residual pressure and again, this is very engine specific. With the gauge still attached the engine is shut off (fuel pump unplugged) and the gauge watched. If the pressure drop over a thirty minute period is more than 20-40 psi the fuel pump check valve or injector(s) is leaking.
Hope I haven't confused you too much. Let me know if you need specific pressures and I'll can and send them to you.
Dennis
There are some good manuals on checking the fuel injections systems at your local auto parts store. I use the factory manuals and the Haynes fuel injection Techbook. If you get one make sure it includes the CIS system. Basically the tests are made on the system pressure and the control pressure. System pressure is normally measured between the center port of the fuel distributor and the outlet of the control pressure regulator (WUR) with the gauge valve closed. Control pressure is measured at the same location but with the valve open. Make sure the valve is on the fuel distributor side of the valve. The correct readings are very engine and temperature specific. Basically system pressure is between 65 and 85 psi. Control pressure should be between 14 and 35 psi depending upon temperature. The gauge setup and valve positions are very specific when testing the CIS. The last check is for residual pressure and again, this is very engine specific. With the gauge still attached the engine is shut off (fuel pump unplugged) and the gauge watched. If the pressure drop over a thirty minute period is more than 20-40 psi the fuel pump check valve or injector(s) is leaking.
Hope I haven't confused you too much. Let me know if you need specific pressures and I'll can and send them to you.
Dennis
