misfire no cel

[mirage1878]

I have an 03 Mazda b2300 it started having a miss a month ago I have tried cleaning mas and throttle bodynstalled New plugs wires coilpack and cam positioning sensor I have even pulled out the 02 sensor to see if the cat was plugged does anybody have any ideas

 

[kryptonitecb]

Get a shop or parts store to check your OBDII for any codes. Not all codes will trip a check engine light.

Sent from the road while ignoring traffic

 

[adsm08]

A misfire code will trip the CEL. Not all misfires will set a code. You need to find a scanner that will do Mode 6 data. The mode 6 will show you which cylinder is missing.


If you did plugs, wires, and coil then your issue is probably a failing injector.

 

[mirage1878]

I ve ran every kind of diagnostic using a ob reader even a drive test and nothing shows up no codes no cylinder missfires if I could narrow it down I could start looking into the injectors

 

[mirage1878]

Ok I was off today so I ran the truck in my garage with lights off and somehow electricity is leaking around 1 boot on the coil pack and arcing on the cruise cable for the first time ever I used there dielectric grease they try to sell you with new wires I cleaned it off and it isn't missing as bad but that would explain the no cel

 

[adsm08]

Dielectric grease is a good thing, when used correctly. But it does become a conductor in high-voltage situations. You have to be careful to not let it get outside the boots because it will let it arc like that.

I would pull all the wires off at the coil and wipe them down.

 

[RonD]

The mis-fire code can be either from coil feedback, computer monitors the coil firing when it grounds the coil.
Or from the CKP(crank position) sensor.
The computer can tell when crank speed is effected by a cylinder not adding power(firing) to the rotation speed of the crank.
Same way you "feel" the miss, the computer can "see" the miss.

Electricity always takes the "easiest" path to Ground.
So arcing means the "spark" finds it "easier" to jump the gap to the cruise control cable than to run down the wire and jump the gap at the spark plug.
The dielectric grease makes the cruise control cable less "easy" to jump to, but it doesn't make the spark plug path "easier"
I would check the resistance in the wire and spark plug.

You also have a dual spark plug system, and BOTH spark plugs firing on the power stroke and BOTH fire on the exhaust stoke, so a spark mis-fire would mean BOTH spark plugs were effected.

I would run some Seafoam in the fuel tank and see if that cleans up a dirty injector.
Injectors need to spray fuel to get the best fuel/air mix, when the tips get dirty they Drip fuel, which can cause random mis-fires.
Premium gas usually has injector cleaners added, not so regular gas, I am cheap and run regular all the time but add can of seafoam once a year.

 

[mirage1878]

Ron d 03 model has single spark plug system I pulled all the wires out cleaned them now it has a very slight miss not noticeable unless waiting for it during acceleration so I'm going to pull plugs clean them and I live by seafoam normally run it every oil change

 

[adsm08]

Ron d 03 model has single spark plug system I pulled all the wires out cleaned them now it has a very slight miss not noticeable unless waiting for it during acceleration so I'm going to pull plugs clean them and I live by seafoam normally run it every oil change

I think that is the way to go. The weak spark may have allowed the plug to foul. It may have also slightly washed the cylinder. Gas wash will keep the rings from sealing properly, but if it is slight it can be reversed by changing the oil and driving the piss out of it.

 

[Milton]

Ok I was off today so I ran the truck in my garage with lights off and somehow electricity is leaking around 1 boot on the coil pack and arcing on the cruise cable for the first time ever I used there dielectric grease they try to sell you with new wires I cleaned it off and it isn't missing as bad but that would explain the no cel

Arcing across the plastic of the coil pack can leave a carbon trail that is a conductor. It can be very hard to clean that carbon trail off completely. I've had success using fine sandpaper on a conventional coil, sometimes you have to replace the coil. Check the plug wire even though it's new, and the plug as well.