1988 Volvo 740 no fuel to engine

1988 VOLVO 740
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MISTER4U
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Engine Mechanical problem
1988 Volvo 740 4 cyl Two Wheel Drive Automatic
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I have an 88 volvo 740 4 cyclinder,im not getting any fuel to the engine.i have changed both fuel pumps and relay and filter i cant hear the fuel pumps come on,any ideas?
Apr 27, 2008 at 7:37 AM
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RASMATAZ
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Have you checked the fuses for the fuel pump. fuse no.11 and no.1?
Apr 27, 2008 at 7:51 AM
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MISTER4U
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acually yes,i did check the fuses,
Apr 27, 2008 at 8:31 AM
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RASMATAZ
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Breakout the voltmeter and test for power at the fuel pump relay female side with the red wire.
Apr 27, 2008 at 8:33 AM
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MISTER4U
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I dont seem to be getting anything on the female side..
Apr 27, 2008 at 2:33 PM
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RASMATAZ
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Fuel pump circuit also check the radio interference suppression relay


https://www.2carpros.com/forum/automotive_pictures/12900_relay1_2.jpg


https://www.2carpros.com/forum/automotive_pictures/12900_relay2_1.jpg

Apr 27, 2008 at 2:43 PM
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EDRUNNER
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Was this problem solved? If it was, it sure will help me. I have the same exact problem on my neighbor's 1989 740 GL station wagon. There's always power to fuse #1 (main pump) even when ignition switch is Off but none on #11 (in-tank pump) even when engine is cranked. When I connected the in-tank pump wire (pink) to #1 fuse spare connector, the pump ran. At least I know the wiring from the relay to the in-tank pump is fine. I don't know why there's no power to the in-tank pump. I'm guessing it's between the relay terminal and the ignition swith or the ECU. Is it? I don't want to change the ECU until I've done other tests which I don't know. Can you tell me what they are? A mechanic said it could be the crankshaft position sensor. Is this correct? Any ideas will be greatly appreciated. I've donated before on a different question as Ed51 but can't access my account so I'm on a new account name.
Aug 3, 2009 at 2:45 AM
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EDRUNNER
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Put direct power to In-tank pump and it ran. With the ignition On there's no power to the main fuel pump. Whe engine is started the main fuel pump also does not run. It runs only when a test light probe touches its blue-yellow wire at the relay terminal. (The fuel pump relay is brand new by the way). We did it this to make sure the new pumps we installed runs and know that there is gas going to the fuel rail. Engine still won't start. Thinking it's the injectors. The Computer Engine Control diagram shows wiring from the Radio Suppression Relay to the injectors and ECU and to the MAF, IAC and ECU. I'm guessing it could also be the Radio Suppression Relay or the ECU that's bad. I'm using Fig. 4: Computer Engine Control diagram ( LH-Jetronic, 16 Valve) diagram. Engine is B230F. Any ideas will be greatly appreciated.
Aug 4, 2009 at 1:15 AM
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EDRUNNER
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By the way, fuses No.1 and 11 (Main pump and In-tank pump respectively) are good but there's no power to No.11 - only at No.1. Fuel pumps and relay are new. No power from fuse 11 to in-tank pump. Wiring is OK.
Aug 4, 2009 at 1:30 AM