rochester 2bbl 86 regal code 45 help!!!!

Discussion in 'The Venerable Q-Jet' started by buickapollo455, Oct 23, 2005.

  1. buickapollo455

    buickapollo455 Well-Known Member

    hello, have a problem cant seem to get rid of, the car is a 86 regal 3.8 2bbl, with a lean code 45, i had bad gas line so replaced, bad fuel pump weep hole so replaced, little dirty fuel filter so changed it, opened air box and car still acts like it is choking or drowning, in flood of fuel, car will die pull over put foot to floor and restart to chug chug and then fast idle, then try again and car flutters on high way, and push gas hard to get off highway at 45 mph, and then dies on ramp when gas is removed, help i disconected batterie each repair and remove memory, from ECM, yet lean code 45 comes back , HELP PLEASE, WIFE NEEDS CAR, PLEASE POST SOON, OR EMAIL c_geske@earthlink.net craig, thanks :confused:
     
  2. Kirk

    Kirk Well-Known Member

    A code 45 is a Rich Exhaust code, not a lean code. If you are getting a code 44 and 45 together, then your O2 sensor (or its wiring) is defective.

    What type of carb do you have? Is it a 2-bbl DualJet (half a QuadraJet) or a progressive 2-bbl VaraJet?
     
  3. buickapollo455

    buickapollo455 Well-Known Member

    not sure looks like a 1/2 quad

    looks like a quad 1/2 in size same filter input as quadrajunk, only 45 comes up and code 12 comes up before and after, as ok ecm, please help
     
  4. Kirk

    Kirk Well-Known Member

    That sounds like the Rochester Dualjet. It's a Rochester Quadrajet with the secondaries removed.

    First off - are you SURE it's running too rich? Pull the spark plugs and see what color they are. If they're all covered in black, fluffy soot, it's running too rich. If they're clean and white, it's running too lean. Check ALL of them - they should all match. If not, you've got bigger problems.

    A Code 45 means the computer "thinks" the car is running too rich. The Electronic Control Module (ie - ECM, 'the computer') tries to compensate by sending a signal to the 'dancing needle' (Mixture Control Solenoid - MCS) in the carb to lean out the mixture.

    Now, one of two things is happening. First possibility - the O2 sensor is correct and the car is running way too rich (black, sooty spark plugs). It could be because the MCS is broken, disconnected and/or not responding, so the mixture needles are pulled up and the carb is running full rich. Or, the Throttle-Position Sensor is broken/disconnected, so the ECM thinks the car is floored all the time and is dumping in a full-rich mixture.

    Second possibility - the O2 sensor is wrong and the car is running way too lean (clean, grey/white plugs). The ECM will be trying to cure the 'rich' mixture by commanding the MCS to shut down the fuel flow, and only at full-throttle will the ECM command the carb to go full rich.

    Your homework is to verify what the computer is telling you. Look at the spark plugs. If rich, check the connectors for the MCS (top of carb, front-right (passenger) corner) and the TPS (front of car, right (drivers) side). Make sure the connectors are on tight, and the wires are frayed, loose or broken.

    If the plugs are lean, check the wiring to the O2 sensor and/or replace the O2 sensor.

    The carb itself is fairly reliable and not likely the culprit. Check the simple/easy stuff first.
     
  5. buickapollo455

    buickapollo455 Well-Known Member

    found out problems

    the 02 was ok, the primary pull off was not opening carb for starting, and would not start , the EFE grid under carb is fried, and it is discontinued, the electric choke has bad contact will have to solder to hook up. Checker auto had primary choke pulloff, after disconnection of battery, primary choke done, solder contact to choke, the car starts runs a bit better, told will now run "lean" until i can find a EFE grid. This car is due for a 455, I hate ECMs go back to good old hei 455 with good cam and duels, thanks craig
     
  6. Kirk

    Kirk Well-Known Member

    The EFE (Early Fuel Evaporation) grid is used to help vaporize the fuel when the engine is cold. They are available in the aftermarket for around $70. Without it, the car will stumble and perform poorly when cold.

    While I can understand the "I hate ECMs(!)" sentiment, realize this: The problems you experienced had nothing to do with the computer. It was a bad electric choke and a defective choke-pulloff. These problems would've happened on any carbureted car. The ECM simply gave you another indication that something was wrong (and it was right!).

    Glad you were able to fix the problem - there are few things more frustrating than a poorly running vehicle.
     
    Last edited: Oct 25, 2005

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