Question about 1991 Volvo 740

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Check engine codes

I would like to know the codes and meanings of the codes for my check engine light

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  • David Westhoff Jun 17, 2008

    321.......221... 1991 740 2.3l non turbo

  • David Westhoff Jun 19, 2008

    ok those codes are gone now....i replaced some stuff... my starter was arcing against my engine.. now my only code is 221

    i think its the oxygine sensor

    car is hard to start, once starts its rough, (press the gas pedal and it almost cuts out then regains , let off the gas and it almost shuts of then it regains....till it warms up then its running good except for the slight fluctuations like i said im assuming the oxygine sensor

  • David Westhoff Jun 19, 2008

    2-2-1 is oxygen sensor on the codes for the ignition on a '91 740 without's the link:

  • Anonymous Mar 10, 2009

    fuel relay!!!!!!!!!! thats it....



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Hi there, the 2-2-1 is a oxygen sensor code, and the 3-2-1 is a cold start valve code, cold start valve is controlled by the radio supression relay, (located by the coolant bottle, closest to the passenger side) the oxygen sensor is powered by the fuel injection relay (or the fuel pump relay) but on the contrary, the supression relay is powered by fuel pump relay. just food for thought, i have a 90 740 non turbo and just got done battling one of the worst inttermittant no start porblem with mine, i too had those two codes, i had some loose wires at the supression relay,.i unplugged the connector, took a dental pick and tightened the conectors in the male end, put it back together and made sure to take that same pick and push all of those wires into the connector, ( there lyed my prob) i could actually start the car, walk around, and move the relay and got the car to kill, i pushed those wires in real quick and the car came back to life. after getting that wrapped up i still had a 2-2-1 code, i drove the car for 20min and the code cleared itself. also you can try putting a couple small holes in the sides of the relay case. this helps vent some heat, those relays are natorious for overheating.

Posted on Mar 10, 2009

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What kind of codes you have

Posted on Jun 17, 2008

  • Henry Roa
    Henry Roa Jun 18, 2008

    it is a P0321 or just 321



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