Hi

have some trouble with misfires.

How can i flash the PCM?

Is it easy to change the PCM?

How to do it?

Thx.

 

I would start with something easier than changing the PCM...Maybe you have a bad coil pack.

 

a pcm reflash or new pcm will not cure missfires...

 

Hi as i said in another thread,i changed coils and sparkplugs.All are MOTORCRAFT parts.

Invert coils and injectors and still have misfire on cylinder#2 & #4.

That's the PCM that gives the spark right?

So the PCM is the last thing to change i guess.

BAST.

 

Misfire doesn't always mean spark failure. Could be a simple vacuum leak or a sign of a more serious internal issue, especially since the cylinders are next to each other.

Do you have any DTCs that would indicate an ignition misfire?

 

No more gay marriage.

I like that.

 

No,the only DTC i have were P2006 that indicates that the bank 2 stys closed.

I changed the CMCV and DTC P2006 didn't came back.

But after changing it,had codes P0302 P0304 P0300 P0316.

NOw CEL is flashing and truck runs rough.

Really need help!!!!!

BAST.

 

were these missfires there after the plug changeor before also on the same cylinders? did you by chance crack the porclin on those 2 plugs installing them? seen that many times if your not on the plug good or have a crappy socket. also did you put dielectic grease on the coil springs?

 

No i don't think any plug had broke when mouting them.

I mount them respecting the torque and they're MOTORCRAFT.

SO i guess plugs are ok.

Did not put dielectric grease.

BAST.

 

The boots are supposed to have dielectric grease in them to insure a good connection. Inspect the glass top of the plugs carefully, make sure they did not get cracked when you installed.

 

I read somewhere that it could be the O2 sensors.

Wht do you think?

 

I really do not know much about the O2 sensors, but it seems to me that it would affect all cylenders, not just those 2.

 

Maybe!!!

But if you read my early posts,

i almost changed everything i could to fix that but truck still runs rough...

I'm in a mess ,i don't know what to do.

 

I feel for you. Be sure and check those porcelan tops on the plugs. Some guys had a similar problem and finally, when they removed a plug, found that the plug was cracked. Had to have it out to see it. Plus, you must have the grease in there as a conductor.

 

A couple things to check...

1) Output voltage to the coil connector of the offending cylinders (primary, NOT secondary circuits) to make sure they are between 12 and 14 volts. Also make sure ground is triggering properly.

2) Same voltage check on injectors along with appropriate ground triggers.

We used to use "NOID" lights to test those circuits, but any 12v bulb will do in a pinch. Those should eliminate the electrical end of things and determine if the PCM is a problem or not.

After that, you may be looking at mechanical issues. Leaking head gasket would be my first choice since the cylinders are adjacent. Manifold or other vacuum leak is another area to check.

The trick is to break down the easiest components to test, which it seems like you've been trying to do. You swapped plugs with no luck and from what I understand, you've also swapped injectors with no luck. All you've got left is electrical and mechanical.

Good luck hunting.