Flashing cel

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protege5
Do you have a scan tool? What cylinder is misfiring?

Diagnosis is key before spending money. There's plenty of parts to swap around. Only swap 1 part at a time! Find out what cylinder is misfiring. clear the codes. Swap plugs with the cylinder next to it. IF the problem follows the spark plug, then replace the plug. If the misfire stays on the same cylinder, then clear the codes again and swap the coils. IF the problem moves to the other cylinder, then replace the coil. if not, then coils are fine. clear the codes again, pull the fuel rail loose and swap injectors between the problem cylinder and another cylinder. clear codes and run it until it misfires. see if the problem follows the injector or not.


If you are burning up coils, then it many times it's a spark plug that can cause coils to burn out. If the plug has too much resistance, or the gap is too large (worn plugs) then it requires the coil to produce more kv to jump the plug gap, shortening the life of the coil.
 
:
Mazda protege5
It's still cylinder 3? Maybe check your plug wires, sometimes the metal insert gets knocked loose even though it feels like it's on there. Sometimes you can push it down enough to seat, I had to get new wires in my case
 
:
protege5
I don't think it was the coil then, i'd bet that was just a coincidence. Time to look elsewhere. If it ran for a couple days before misfiring again, possibly a coil. But a new coil frying within minutes is unlikely. That's really not even enough time for it to warm up.

Run the car and let it misfire for a few minutes. Then immediately pull the spark plug out and inspect. See if the spark plug is wet? Dry?

I'm suspecting an injector has or is failing. I know how some like to say these coils go bad left and right but I sold my car with 270k miles on it, still all of the original coils and wires and I never had a problem with them so I'm still not completely sold that the coils are junk...
 
:
Mazda P5
Well i switched the coils and it jumped from 3 to 4. And I did the 626 valve cover swap so I'm running protege coils. It was running fine for 5 months before this happened.
I swapped plugs and wires still the same coil. I put it new coil same problem. So I'm wondering what's making the coil go bad.
 

pcb

The Diagram Dude
:
2002 MP5
New coil in, flashing cel came back. So what causes a coil to burn out?
I think your coils are crap.

I think you should go with Hitachi coils.



A lot of guys have had a lot of problems with coils. Including being bad right out of the box.

Quality coils are worth the money.
 

pcb

The Diagram Dude
:
2002 MP5
OK. I didn't know what you meant by "Protege Coils".

The issues may be different than the COP coils from the P5.
 
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:
Mazda P5
Yeah so I'm not sure. I'm hoping it's something simple, it turned the spark plug black. But I put it in cylinder 2 and it's fine for now. So I'm not sure if the injector is stuck open.
 
:
Mazda P5
Yeah, I switched the fuel injectors between 3 and 4 the o ring went bad and started spraying fuel. So now I can't do anymore tests until I get that fixed.

I just bought a remanufactured injector off of Amazon for $50 overnighted for tomorrow.
If that doesn't fix it I'll send back my old one and say it didn't fit.
 
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:
protege5
black spark plug is usually an indicator of a weak spark, or running way too rich.

Since you've got the same problem with new coil I'm thinking the injector is probably stuck or sticking (it can be intermittent) and it's fouling out the plug.

I'm not familiar with the swap, how hard is it to do? Would it be a real PITA to swap back to the original setup, at least to test and see? Also, what are your plugs gapped at? And do they require a different gap with the coil conversion?

Of curiosity, what do you gain from the coil conversion?
 

pcb

The Diagram Dude
:
2002 MP5
I'm pretty sure the original COP coils won't fit on the 626 valve cover.



My car ...



From what I remember reading, there's not much to be gained from the 1.8 L coil swap.
Perhaps maybe more reliable coils ??
 
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pcb

The Diagram Dude
:
2002 MP5
I'm a little confused.
Did the misfire always follow the coil ?

If you have a sticking injector, the misfire should always be on that cylinder.

Perhaps something is straining your coils making them fail or they are shorting to the valve cover.

Either way, I think the coils should be able to deal with those rough conditions and not crap out when stressed.
(PS.. I quite biased. I'm a coil hater lol)
 

pcb

The Diagram Dude
:
2002 MP5
Rock Auto doesn't have an OEM supplier for your ignition coils.
(these are Canadian dollars)



Online Mazda Parts has the OEM part.
(US dollars)

 
:
Mazda P5
The misfire did follow the coil but something has to be burning the coil out. So it might be that my jet is stuck open and the coil can't keep up the stress from the fuel maybe. I don't know I'll find out when I get the new injector. I still have the other coils to send back she I'll take off the extra one.
ZFR5F-11 these are the plugs in using.
 

pcb

The Diagram Dude
:
2002 MP5
The misfire did follow the coil but something has to be burning the coil out...
Or they're just complete crap !?!? Bad right out of the box ??

The aftermarket coils are built to a minimum spec. The OEM coils meet a much higher standard.

You're dealing with hot summer weather now and that could be the trigger to blow new coils.

Ignition coils are the only part on my car that I would spend the money on an OEM part.
 

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