Question about Mitsubishi Mighty Max

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No acceleration power

Only when the engine is cold, and the check engine light comes on while on the highway, it will decelerate like my foot is off the gas no matter how much I press it. I have to take my foot off the gas completely and re apply it to get the car to try and accelerate again. it sometimes bucks and sputters during throttle as long as the check engine light is on, which is again only first thing in the morning. if I pull over and cut it off and restart it, the light is still on, and after a few minutes it will shut off on it's own and it runs fine like nothing ever happened. all sensors are plugged in securely and dry. I recently changed the plugs, wires, cap, rotor, pcv valve (and cracked the valve cover tightening it down) fuel filter, and air filter. could this be a mass air flow sensor, o2 sensor, or egr valve? I did push the diaphram in the egr valve up and it moves freely. and for backround purposes I did seafoam the truck like a week ago by pouring in through brake booster line into the intake manifold. thank you

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Any trouble codes? There should be a code registered by now. That should point you to the problem. And if not, you probably need to look at the sensors data feed when the problem is going on. Look at live streaming data, I mean, the MAF, oxygen sensor, in fact all of the sensor data.

Posted on Mar 06, 2017


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Posted on Jan 02, 2017

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SOURCE: 1994 Lexus LS400 Engine Cuts out when accelerating

could be your fuelm pump is going out on you.

Posted on Aug 26, 2009

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SOURCE: I have a chevy silverado - 5.7 engine. It runs

Fuel Pressure/Pump?
Fuel Pressure Regulator?
Are there any codes/check engine light?
Ignition coil?
Just off the top of my head.

Posted on Mar 11, 2010

  • 1 Answer

SOURCE: van sputters whenever you go to take off from a

hi there, i had the same problem with my 98 astro van, and took it to the shop, the computer pumped out a mass airflow sensor, they replaced it at considerable cost lol, but the van now runs good

Posted on Jul 03, 2010

  • 30 Answers

SOURCE: i have changed my o2 sensor crank sensor knock

wats it doing?

Posted on Nov 28, 2010

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SOURCE: 2004 Silverado 4.3 V6

Check engine light on? Any codes? Missed before and after the cap was changed? Or is the cap new so you assume its good. I have had caps bad out of the box.

Posted on May 29, 2011

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