4.6LPoppy

[sm=helpout.gif] How can you tell if you have a bad coil on plug? In the past I have stuck a new one in the holes until I found where it smoothed things out. What happens if you have 2 bad? This method won't cut it. Is there a tester?

GT 281

Feed him a donut.

4.6LPoppy

Somehow, I knew this would happen. Good answer though. (Still need to know)

mikev08826

Kind of a bogging feeling...it will feel like your only running on 7 cylinders...tough to explain...

4.6LPoppy

I know that feeling from previous 4.6's, but they were all essentially stock, either SOHC or DOHC. This one has Procharger, MSD ignition, 42lb injectors, etc, etc. and I can't tell if it is from some of that or if I have a bad COP or COPs. It runs GREAT when I step on it but is real rough around 1300 rpm.

Sap

You will get a Check engine light if one goes bad. I also imagine it would be pretty obvious as one cylinder would just stop working.

E.

Fallstar01

It should throw a code telling you which cylinder isn't fireing correctly.

4.6LPoppy

The minority of my engine is not stock so the eng light is always on. A COP can go 10% bad/weak. When one is going bad it starts with just a slight hiccup now and then.

aode08

NO YOU WILL NOT GET A CODE 70% of the time till the car does not want to run

Have it put on Oasis at Ford, you may have several issues, . Had a 4.6 with 4 bad Cops and it idled wierd and miss every now and then.

No codes, Oasis will test each one and monitor the system, way better than the ECM can do its own self[:-]

if you have a bad cop, I have 8 Excellent ones from Ford. What we do is repalce all eight under warranty and keep the good ones to ourselves, in this guy case, his misfire were the garbage platinums in the motor and not the COP'S, so I have 8 of em with 10k on them, still smells brand new from an 2002 4.6

sk8erdudex

pull the engine codes if the light is on. It will tell you all the codes. Including which cylinders suck