hey so i used the scanner at oriellys auto parts and this is what it says.
code p0300 random missfires. .... and then it shows all of these all in the same code:
Fuel system loop 1= open loop
Calculated load= 94%
Mass air flow sensor= 002.6
Throttle position sensor= 0.0%
Engine rpm= 1265 rpm
LTFT Bank 1= -1.5%
Intake Manifold Press=15.9 in.H9
Engine Coolant Temp= 73 degrees F
STFT Bank 1= -0.7%
What does this mean????
one of my spark plug wire was burnt it touched something that got hot and put a hole in it so i bought a new set "Omni Spark". i took my spark plug wires off and did not label them "dumb on my part" so i understand that there not in the right order as i dont have a book but what does the rest of the stuff mean? and can anybody help me with putting spark plugs in rite order maybe no a site that can show me a diagram "site for dumbies or something lol".
code P0300 = random missfires????? 96 bonneville se
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Ilovemybonnie
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Re: code P0300 = random missfires????? 96 bonneville se
First thing to do is check your coolant level and color of your oil. Be very careful about this one, and do it RIGHT AWAY. Coolant leaking in the UIM EGR passage or through the ports of your LIM gasket will cause multiple misfires and will kill your motor if you don't catch it in time. If you haven't replaced your LIM gaskets or UIM with the improved design, and flushed out all the DEX-cool (and never put it back), you're on borrowed time.
For your plug wires, you get what you pay for. I've never heard of that brand. Take them back and get name-brand wires, and never buy auto parts at Autozone (in case you did). It looks like the O-Reilly's cheapo store brand.
2, 4, 6 from left to right in the rear, 2 being closest to your alternator, 6 being closest to the driver.
For your plug wires, you get what you pay for. I've never heard of that brand. Take them back and get name-brand wires, and never buy auto parts at Autozone (in case you did). It looks like the O-Reilly's cheapo store brand.
To get things back in order, stand FACING the engine with the hood up. The front three cylinders will be 1, 3, 5 from left to right facing the engine, 1 being closest to the coils.those omni wires are crap the plugs get loose and fall off and sometimes they just pop out.. but if your low on funds go ahead and get them as temps but inspect the sockets and tips before you buy them...i worked at oriellys and 8/10 sets were crap
2, 4, 6 from left to right in the rear, 2 being closest to your alternator, 6 being closest to the driver.

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mhfromphila
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Re: code P0300 = random missfires????? 96 bonneville se
The order is 6,3 starting at the top coil. middle coil is2,5,bottom coil is4,1. I would have changed the plugs at the same time.#1cyl. is front/left next to the coil pack #3 cyl. front middle. #5 is front right.#2 is rear left. #4 is rear middle #6 is rear right.All info is from looking from the front of the car.Your not he first guy that mixed up is wires and had a car run like crap.I've done it more than once.Good luck. 
1993 SE mag.cat., K&N CAI, B&M drain plug, MSD wires, Energy Suspension end links, Monroe sensotracks,3.06gears,F41,N10,adj.modulator,180 degree stat. SilverStar Ultra highs and lows,TR55 plugs,DEX VI,front trans mount mod.
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Ilovemybonnie
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Re: code P0300 = random missfires????? 96 bonneville se
thanks for the replys guys so i went and checkd coolant level and its mixd with water and oil is deffinently old. another thing i forgot to menchion is i dont have a rubber gasket"i think its calld" in the inside of the oil panel and the right bottom corner smokes like its burning oil. its never done this before. i dont think any coolant leaked in the
willwren wrote:First thing to do is check your coolant level and color of your oil. Be very careful about this one, and do it RIGHT AWAY. Coolant leaking in the UIM EGR passage or through the ports of your LIM gasket will cause multiple misfires and will kill your motor if you don't catch it in time. If you haven't replaced your LIM gaskets or UIM with the improved design, and flushed out all the DEX-cool (and never put it back), you're on borrowed time.
For your plug wires, you get what you pay for. I've never heard of that brand. Take them back and get name-brand wires, and never buy auto parts at Autozone (in case you did). It looks like the O-Reilly's cheapo store brand.
To get things back in order, stand FACING the engine with the hood up. The front three cylinders will be 1, 3, 5 from left to right facing the engine, 1 being closest to the coils.those omni wires are crap the plugs get loose and fall off and sometimes they just pop out.. but if your low on funds go ahead and get them as temps but inspect the sockets and tips before you buy them...i worked at oriellys and 8/10 sets were crap
2, 4, 6 from left to right in the rear, 2 being closest to your alternator, 6 being closest to the driver.
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Ilovemybonnie
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- Joined: Sun Jun 26, 2011 12:59 am
- Year and Trim: 1996 Bonneville 4door not fuel injected
Re: code P0300 = random missfires????? 96 bonneville se
what would u suggest i do next i put new spark plug wires in and all in the order u told me to and it started up. and yes im just using those for temporary use i just wanna find out what the problem is for my car because it shuts off and if anyt of them other codes mean anything. the scanner said mass air flow sensor nad throttle position sensor so should i just buy those and it should work or....

