I changed my plugs and I still have a miss. The miss is not as bad as it was before, but it is still there. Now I can build some boost before i get the miss. here is some pics of the plugs:


this pic shows what 6 of my plugs look like along with what 2 of them look like


shows the 2 plugs side by side


another side by side.

2 plugs looked like crap and the other 6 looked ok.

So now that I know that its still missing, where do I go from here? Take it in and have diagnostics run on it to see if its a coil? Maybe i have a couple injectors taking a crap? maybe I have crap in the injectors. And yes, it has a new fuel filter in it with less than 300 miles on it.

link to my original thread:
https://www.f150online.com/forums/sh...hreadid=192570

Any ideas Sal?

Chris

 

sounds to me like a bad fuel injector or a bad coil pack, which one i have no idea... but it looks like u have the same ideas. Id take it in... goodluck

 

Looks like the plug not firing.

I would second checking the coil pack...

Also check the injestor, hee hee.....

 

Personally, I think it the sorry Denso plugs. I had the same problem recently. Changed to NGK BR7....no problems now!

 

I am not a big fan of Denso's also!

One other thing to check, the break booster vacume lines. Remove them and inspect them if there is a black shoe polish resadue on your hands and if the hose looks like it is cracked or has alagator skin pattern the hose is bad.

My truck fried a head on the dyno last year due to this issue. I could never figure out why I kept burning plugs. I hadn't changed any thing but a chip. I even went back to the old relyable chip and set up and would stil burn plugs at WOT.

Sal was the one who tought me this! What happens is that the fuel rail will not allow you full fuel pressure thus the lean condition.

Hope this helps,

Peace,

Suavy

 

Ditto on the coil pack.

I'm also running BR7's with about 15 lbs of boost (ported eaton). Truck has a slight shimmy (miss) at idle, but it did even stock, so I can live with it. Other than that they perform beautifully.

I recently thought of trying the Denso's but think I'll save my $$ and stick with what I have.

Steve

 

I was thinking of using NGKs, but sal thought the denso heat range was better for my application.

Also, the burnt looking plug has residue on it. its like someting cooked onto the plug. One of the guys at work thought it might be antifreeze, but I dont have any of the water leak type signs. No smoke, no oil in the water or water in the oil.

I think I will see what my dealer has for test equipment today while I have the wifes explorer in. I might anti up and pay them their $65 per hour.

Chris

 

I also switched to denso plugs and my truck is skipping bad pulled them all to check them no.8 was like melted i changed it and changed no.8 coil pack still skipping denso suck......and to think i paid $100 for them i had ngk's at first i had no problems

 

Looks like the two plugs that are fouled either had water and crap getting to them from the top or they had backed out. I say this because of the black on the ceramic and all the gunk on the threads and the part right under the ceramic.

Have had great luck with Denso but think I will go to the NGK TR6's for the cext plug change because I have heard good things and would like to try them for the price.