I cant figure out my random cylinder misfire in all 6 cylinders.

Tiny
KODYCLARENCE
  • MEMBER
  • 1996 CHRYSLER SEBRING
  • 166,000 MILES
My vehicles check engine light flashes quite often at random times, and random speed. It gives me random cylinder misfire codes from P0300 to P0306. I have changed the EGR valve, distributer cap, rotor, plugs, and wires and would like to know where to go from here.
Sunday, October 7th, 2012 AT 7:14 AM

23 Replies

Tiny
KHLOW2008
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Check the fuel pressure and try replacing the fuel filter if it is a long time since it was last replaced.
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Sunday, October 7th, 2012 AT 8:03 AM
Tiny
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Ok. I will do that. I don't believe my vehicle has a fuel filter. I haven't checked but it was mentioned to me that that particular vehicle doesn't. Another thing is when I am driving and my vehicle starts to misfire the car will jerk once for just a second and it shuts the check engine light off and turns it back on. Not like a flash like when it misfires. Sometimes it will do that a couple times in about 2-3 second intervals. Now that you mention fuel pressure it could be that it loses fuel completely for a second.
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Sunday, October 7th, 2012 AT 8:41 AM
Tiny
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With such symptoms, I believe it is more likely to be electrical rather than the fuel pressure.

Check for loose connections of wire connectors, especially those around the PCM.

All vehicles would have a fuel filter only the location differs. Which engine do you have?
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Sunday, October 7th, 2012 AT 8:55 AM
Tiny
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It is the 2.5 V6 DOHC. I've checked all of the wiring to emissions components and things like that and they all seem to be fine. No cracks, corrosion, loose connections, nothing. I thought maybe the 02 sensors were setting it off, but no 02 sensor codes are popping up. I've hooked a scan tool up to it and checked the freeze frames and it says its setting the codes off at about 68 MPH. But the engine light will go off at random speeds.
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Sunday, October 7th, 2012 AT 9:27 AM
Tiny
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If thee is a fault, the MIL should stay on under normal circumstances. Blinking MIL indicates it is most likely related to the PCM.
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Sunday, October 7th, 2012 AT 9:30 AM
Tiny
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Is that the computer of the vehicle?
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Sunday, October 7th, 2012 AT 9:38 AM
Tiny
CJ MEDEVAC
  • MECHANIC
  • 11,004 POSTS
Fuel-Filter
IF THIS AIN'T BEEN CHANGED IN .......LIKE FOREVER

IT'S TIME!

WHETHER THIS IS THE PROBLEM NOW...OR NOT

THE "ASTU MAINTENANCE SCHEDULE" (AS STUFF TEARS UP) WORKS, BUT USUALLY IS IMPLEMENTED AFTER MUCH PREVENTABLE HEARTACHE

"THE PREVENTATIVE MAINTENANCE PROGRAM" GENERALLY KEEPS YOU.....HAPPY AND WITH A SMILE ON YOUR FACE!......THIS MIGHT BE THE KEY TO MANY OF YOUR PROBLEMS.....SEE MY LINK

https://www.2carpros.com/questions/2007-ford-taurus-tune-up

NOW THAT YOU HAVE BEEN INTRODUCED TO WHAT A BOOK CAN DO FOR YOU,

SORRY.......YOU WERE ALSO EXPOSED TO "REAL VEHICLES" IN THAT LINK...SEE THIS LINK ALSO

https://www.2carpros.com/questions/1995-mitsubishi-eclipse-knocks-smokes

KEEP US POSTED

THE MEDIC

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Sunday, October 7th, 2012 AT 1:35 PM
Tiny
KHLOW2008
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Yes, PCM is the engine computer.
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Sunday, October 7th, 2012 AT 1:40 PM
Tiny
CJ MEDEVAC
  • MECHANIC
  • 11,004 POSTS
MORNIN' TO YA KHLow2008

WON'T YA SWING BY HERE AND PICK ME UP. WE COULD GRAB US TWO SAUSAGE, EGG, AND CHEESE BISCUITS, A BOWL OF GRITS, TWO INDUSTRIAL SIZED GLASSES OF 32.2 DEGREE FAHRENHEIT MOO JUICES (MILK)?. EACH, THAT IS, AND YOU COULD PICK UP THE TAB.'LESS-UN YOU WANNA GO IN ONE OF MY JEEPS. AND STILL PICK UP THE TAB!

HURRY.I AM PRETTY HUNGRY!

THE MEDIC
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Sunday, October 7th, 2012 AT 1:59 PM
Tiny
KHLOW2008
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Just past the 10 pm mark here, I should be going for supper, lol.
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Sunday, October 7th, 2012 AT 2:05 PM
Tiny
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Ok. Well ill check fuel pressure and change the fuel filter first. I can imagine that is cheaper than the PCM. I have had the vehicle for 2 years now and haven't changed the fuel filter and I highly doubt the people that had it before me did either. Ill throw some Sea Foam in the tank afterwards as well. If that doesn't solve the issue and I get a new PCM will I have to get it flashed like an ECM?
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Sunday, October 7th, 2012 AT 2:38 PM
Tiny
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Changing the fuel filter is not as easy as it seems for the V6. You might have problem accessing it and according to the manual, the tank has to be drained and partially dropped.
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Sunday, October 7th, 2012 AT 2:51 PM
Tiny
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That's ok. I've got a car lift and a transmission Jack. I noticed that it sputters and misfires A LOT more when I have overdrive off. I usually drive with it on.
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Monday, October 8th, 2012 AT 2:14 AM
Tiny
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With OD off, the engine would be runnig at a higher rpm and with more engine torque, the misfiring shoud be felt less.
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Monday, October 8th, 2012 AT 2:26 AM
Tiny
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It runs around 3500 RPM with OD off on the highway and it does misfire and sputter a lot more. Then when I turn overdrive on and the RPMs drop it stops. Sputtering and misfiring as much.
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Monday, October 8th, 2012 AT 2:39 AM
Tiny
KHLOW2008
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Get the fuel filter replaced and see if it makes any changes.
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Monday, October 8th, 2012 AT 3:14 AM
Tiny
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Ok. Ill do that.
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Monday, October 8th, 2012 AT 6:44 AM
Tiny
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I changed the fuel filter. It was bolted to the frame so I did not need to drop the tank. But it is still misfiring :/
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Friday, October 12th, 2012 AT 11:57 AM
Tiny
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Are the trouble codes still showing the same codes or are there any additional codes?
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Friday, October 12th, 2012 AT 12:43 PM
Tiny
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They're all the same.
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Friday, October 12th, 2012 AT 4:32 PM

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