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Drew, Super Mazda Tech.
Category: Mazda
Satisfied Customers: 2518
Experience:  19 yrs. experience. Mazda Senior Certified Tech, with Ford, Linc. & Merc. experience. ASE L1 Advanced Certified Master Tech.
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Mazda Mpv: i have a Mazda 2004 MPV 3.0L V6. after it warms

Customer Question

i have a Mazda 2004 MPV 3.0L V6. after it warms up the engine surge when acceleration. Like a empty spot as it surges. Need help!
Submitted: 4 years ago.
Category: Mazda
Expert:  Drew replied 4 years ago.
Welcome to Just Answer. My name is Drew and I will be glad to assist you.

Is the check engine light on or are there any fault codes stored in the computer??

Does the engine feel like it is having a misfire on acceleration??

Have you replaced any parts to resolve the concern??

How long has this concern been present??

Customer: replied 4 years ago.

no check engine light is on and no codes picked up, yes it feels like a misfire No parts replaced. It started about 2 weeks now.

Customer: replied 4 years ago.
Relist: Other.
need a response to my question soon
Expert:  Tim Mohr replied 4 years ago.
Hi, my name is Tim, does it only do this when accellerating? doe sit do it when cruising?
Customer: replied 4 years ago.

can feel like a little miss while cruzing

Expert:  Tim Mohr replied 4 years ago.
have you checked the fuel presure yet?
Customer: replied 4 years ago.

no where do i check that?

Expert:  Tim Mohr replied 4 years ago.

you will need to hook up a amnual fuel pressure gauge to th

e fuel rail, inline with the pressure hose, then start the vehicle, the fuel pressure needs to be at least 61 psi, if it is lower, then replace the pump, but also you may need to drive it with the gauge on it, to see what the pressure is when its acting up,Tim





Customer: replied 4 years ago.

ok changed the fuel pump runs great when cool but misfire after warm up. scanning reads random misfire. Whats next.

Expert:  Tim Mohr replied 4 years ago.
did you check the fuel pressure? what was the actual pressure?
Customer: replied 4 years ago.

I dont have a fuel pressure gauge so just went ahead and replace the fuel pump.

Expert:  Tim Mohr replied 4 years ago.
ok, well then, if it has misc missfire codes codes, then we will assume its an ignition problem, are you using a scanner to get codes or just a code reader?
Customer: replied 4 years ago.

i'm using a snap on solas scanner.

Expert:  Tim Mohr replied 4 years ago.
ok, on this scanner, you have missfire data, on that screen, when its missing, are there any cylinders that have missfire counts?
Customer: replied 4 years ago.

Yes first code was P0306, cleared it then next code was P0301 cleared that then randon misfire appeared.

Expert:  Tim Mohr replied 4 years ago.
you need to read the missfire counter in the scanner, not just the codes, the missfire counter will show any misses present at the time, and also the history of each cylinder for misses, can get this info?
Customer: replied 4 years ago.

number 1 cylinder appeared first cleared then number 6 cylinder appeared cleared that then code P0300 came out as randon misfires.

Expert:  Tim Mohr replied 4 years ago.
you are not understanding me, those are just missfire codes, there is a place under the datastream of the scanner that reads live missfires and also records the history of each cylinder, that is the info we need? can you check this?
Customer: replied 4 years ago.

our scanner dont do that on this car for some reason, thatts why its hard for us to figure out.

Expert:  Tim Mohr replied 4 years ago.
I own a solas, and it reads the data on the MPV;s I have had it on, I will opt out and see if another expert has any different ideas,Tim
Expert:  Drew replied 4 years ago.
Hello it's good old Drew again.

I see that you relisted after my info request because it took me too long to respond. Sorry for the delay but I am a really busy guy with a full time job and family. This is just a hobby to help people out.

I see that it didn't;t get you any where gut cost you more money installing a fuel pump for no reason!!

Since Tim has now opted out and asked me to step back in, I will be glad to assist but you will need to be patient with me.

Remember, you get what you pay for........

No to start over, I asked you a few question to gather some information. You answered those questions but now your conversation with Tim says that you do have fault codes for misfires which confuses me????

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Since your concern feels like a misfire and you have misfire code, I suggest cleaning the MAF sensor (located in the air filter housing) with a shot of throttle body cleaner. Next clean the throttle body bore and throttle plate with the cleaner to remove the black carbon build-up.

Make sure you fuel is not contaminated or dirty.

Here is what I see on all these vehicles. If you have a misfire that is ignition related, I would replace all three rear ignition coils, spark plugs and upper intake gaskets. Check for any sign of oil in the spark plug holes. That indicates a valve cover gasket leaking. Test drive and if you still have a misfire, install the old rear ignition coils and spark plugs in the front cylinders and test drive for change. That should resolve your concern unless you have a faulty injector but not very common.


Here is a diagnosis test of items to check for engine surges concern.

2004 - MPV - Workshop Manual - Engine



Engine stalls/quits—acceleration/cruise

Engine runs rough—acceleration/cruise






  • Engine stops unexpectedly at beginning of acceleration or during acceleration.

  • Engine stops unexpectedly while cruising.

  • Engine speed fluctuates during acceleration or cruising.

  • Engine misses during acceleration or cruising.

  • Vehicle bucks/jerks during acceleration, cruising or deceleration.

  • Momentary pause at beginning of acceleration or during acceleration

  • Momentary minor irregularity in engine output


  • A/C system improper operation

  • Erratic signal or no signal from CMP sensor

  • Air leakage from intake-air system parts

  • Purge solenoid valve malfunction

  • IAC valve improper operation

  • EGR valve malfunction

  • Erratic signal from CKP sensor

  • Low engine compression

  • Vacuum leakage

  • Poor fuel quality

  • Spark leakage from high-tension leads

  • Air cleaner restriction

  • PCV valve malfunction

  • Improper valve timing due to jumping out of timing belt

  • Restriction in exhaust system

  • Intermittent open or short in fuel pump circuit

  • Inadequate fuel pressure

  • Fuel pump mechanical malfunction

  • Fuel leakage from fuel injector

  • Fuel injector clogging

  • Intermittent open or short of MAF sensor, TP sensor and VSS

  • ATX malfunction


  • The following troubleshooting flow chart contains the fuel system diagnosis and repair procedures. Read the following warnings before performing the fuel system services:

    • Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames away from fuel.

    • Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel can also irritate skin and eyes. To prevent this, always complete “BEFORE REPAIR PROCEDURE” and “AFTER REPAIR PROCEDURE” described in this manual.



Diagnostic procedure





  • Verify following:

    • Vacuum connection

    • Air cleaner element

    • No air leakage from intake-air system

    • No restriction of intake-air system

    • Proper sealing of intake manifold and components attached to intake manifold: EGR valve, IAC valve

    • Ignition wiring

    • Fuel quality: proper octane, contamination, winter/summer blend

    • Electrical connections

    • Smooth operation of throttle valve

  • Are all items okay?


Go to next step.


Service as necessary.

Repeat Step 1.


  • Connect WDS or equivalent DLC–2.

  • Turn ignition key to ON (Engine OFF).

  • Retrieve any DTCs.

  • Is “PASSED” displayed?


    No DTC is displayed:
  • Go to next step.


    DTC is displayed:
  • Go to appropriate DTC test.


  • Is engine overheating?


Go to symptom troubleshooting “No.17 Cooling system concerns—Overheating”.


Go to next step.



Go to next step.


    RPM PID:
  • Inspect CKP sensor and related harness for vibration and/or intermittent open/short circuit.

    MAF PID:
  • Inspect for open circuit of MAF sensor and related wire harness intermittently.

    TP PID:
  • Inspect if output signal from TP sensor changes smoothly.

    VSS PID:
  • Inspect for open circuit of VSS and related wire harness intermittently.


  • Visually inspect CKP sensor and teeth of crankshaft pulley.

  • Are CKP sensor and teeth of crankshaft pulley okay?


Go to next step.


Replace malfunctioning part.


  • Inspect spark plug conditions.

  • Is spark plug wet, covered with carbon or grayish white?


    Spark plug is wet or covered with carbon:
  • Inspect for fuel leakage from fuel injector.

    Spark plug is grayish white:
  • Inspect for clogged fuel injector.


Install spark plugs on original cylinders.

Go to next step.


  • Remove and shake PCV valve.

  • Does PCV valve rattle?


Go to next step.


Replace PCV valve.


  • Inspect that throttle lever is resting on throttle valve stop screw and/or throttle valve orifice plug.

  • Is lever in correct position?


Go to next step.


Replace throttle valve body.


  • Inspect for restriction in the exhaust system.

  • Is there any restriction?


Inspect exhaust system.


Go to next step.


  • Install fuel pressure gauge between pulsation damper and fuel distributor.

  • Connect jumper wire between F/P terminal at DLC in engine compartment and GND.

  • Turn ignition key to ON (Engine OFF).

  • Is fuel line pressure correct with ignition key at ON?

Fuel line pressure

420—460 kPa {4.3—4.6 kgf/cm 2, 61—66 psi}


Go to next step.


    Zero or low:
  • Inspect fuel pump circuit.

  • Inspect for open fuel pump relief valve.

  • Inspect for fuel leakage inside pressure regulator.

  • Inspect for clogged main fuel line.

  • Inspect pressure regulator for high pressure cause.

  • Inspect for clogged fuel return line.


  • Visually inspect for fuel leakage at fuel injector O-ring and fuel line.

  • Service as necessary.

  • Does fuel line pressure hold after ignition key is turned OFF?


Go to next step.


Inspect pressure regulator diaphragm condition.

  • If condition is okay, inspect fuel injector.

  • If condition is not okay, replace pressure regulator.



  • Following test is for engine stall with A/C on. If other symptom exists, go to next step.

  • Connect a pressure gauge to A/C low and high pressure side lines.

  • Turn A/C on and measure low side and high side pressures.

  • Are pressures within specifications?



Go to next step.


If A/C is always on, go to symptom troubleshooting “No.24 A/C always on/A/C compressor runs continuously”.

For other symptoms, inspect following:

  • Refrigerant charging amount

  • Condenser fan operation



  • Following test is performed for symptom with cruise control on. If other symptom exists, go to next step.

  • Inspect cruise control system.

  • Is cruise control system okay?


Go to next step.


Repair or replace malfunctioning part.


  • Disconnect vacuum hose between purge solenoid valve and intake manifold from purge solenoid valve side.

  • Plug opening end of vacuum hose.

  • Drive vehicle.

  • Does engine condition improve?


Inspect if purge solenoid valve is stuck open mechanically.

Inspect EVAP control system.


Go to next step.


  • Visually inspect CMP sensor and projections of camshaft pulley.

  • Are CMP sensor and projections of camshaft pulley okay?


Go to next step.


Replace malfunctioning parts.


  • Inspect EGR system.

  • Is EGR system okay?


Go to next step.


Replace malfunctioning parts.



Inspect following:

  • Valve timing

  • Internal transaxle part


Inspect for cause.


  • Verify test results.

    • If okay, return to diagnostic index to service any additional symptoms.

    • If malfunction remains, inspect related Service Bulletins and/or On-line Repair Information and perform repair or diagnosis.

      • If vehicle is repaired, troubleshooting completed.

      • If vehicle is not repaired or additional diagnostic information is not available, replace or reprogram PCM.

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