1988 Jaguar XJ6 no spark or fuel flow when cranking other t

1988 JAGUAR XJ6
88,000 MILES • 6 CYL • 2WD • AUTOMATIC
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JAMES W.
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this problem started after a normal shut down.
would not restart. I have replaced the air flow meter, then the ECU with no help. Before I changed anything it would start but not come off idle. eventually I had nothing. Then I started changing the above parts. I am now looking at the crankshaft pos. sensor. Am I on the right track? I Had My own repair shop for 14 years, but this one has me stumped. The book (HAYNES) just tells you just enough to confuse you. I have no check engine light, never have. I think the wire has been cut. I'm working that. Can't pull codes. The car hasn't been driven in 5 years because of this problem. Any ideas??? Jim Weizel
Sep 28, 2008 at 10:17 AM
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RASMATAZ
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1988 Jaguar XJ6 no spark or fuel flow when cranking other t

Do you hear the fuel pump come On when key at run position-If not check for power at the fuel pump connector blue and red wire. Power there fuel pump is defective. No power check fuel pump relay-relay okay-test the main relay it powers the fuel pump relay/coil/injectors.
Sep 29, 2008 at 3:04 AM
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JAMES W.
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[quote:c5daa5f210="rasmataz"]1988 Jaguar XJ6 no spark or fuel flow when cranking other t

Do you hear the fuel pump come On when key at run position-If not check for power at the fuel pump connector blue and red wire. Power there fuel pump is defective. No power check fuel pump relay-relay okay-test the main relay it powers the fuel pump relay/coil/injectors.[/quote:c5daa5f210]
the fuel pump comes on for a second or two when I turn the key to run, then quits. cranking the motor/no fuel or spark. I can manually close the pump relay and it would run until the tank went dry. With key in the run position I have power to the positive side of the relay coil (term #86, white/brn wire. I have no ground to term. #85-pink/brn-coming from the ECM. Keep in mind, I have changed ECMs and aie flow meter, but the problem remains the same. Also, I still have no spark. HEEEEEEELP
Sep 29, 2008 at 6:38 PM
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RASMATAZ
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Did you test the main relay?
Sep 29, 2008 at 7:21 PM
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JAMES W.
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yes, the miain relay IS closing. That is what supplies power to the fuel pump relay, which I have. I have 12 volts to the coil on the FPrelay but no ground from the ECM to close the relay. Would the crankshaft position sensor failure cause this, telling the ECM that the motor isn't turning. therefore not to send fuel or spark. Just an idea, I have a crank sensor ordered anyway. Maybe I should take up basket weaving or something.
Sep 30, 2008 at 10:44 AM
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RASMATAZ
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Have you inspect and test the CPS-The job of the CPS is to identify the position of the pistons and provide engine speed. The computer needs the CPS signal to tell the ignition control module to fire the coil with out it -its like having a dead coil. I'll wait till you install the new one then will go at it again.

Also did you check for injection pulses and fuel pressure-for no fuel?
Sep 30, 2008 at 10:53 AM