07 with cyl 6 misfire help

[mdec950]

yes i did change out the spark plug #6 with another new one from another store

 

[svtfiveoh]

I had the same problem, I end up having to change the Mass air sensor.. Have you tried to at least clean yours ?

 

[mdec950]

Latest

Local ford dealer wanted 956.00 to change out fuel injector. I laffed
Took to a real mechanic. Found all plugs good. They r all new
Found all 8 coil on plug good. All new too
Found all injectors good. 1 on 6 new
Compression 90 on cyl 6
Should be 105-150
I bet head on cyl 6 side has hairline crack

Oh chk eng lite cyl 6 misfire still there

Any ideas ?

 

[mdec950]

Cleaned mass air flow and new air and fuel filters

See above

 

[mdec950]

help .... cyl 6 misfire 07 expedition

friend had a snap on scanner tool
shows all plugs good
shows all coil on plug good and within tolerances
shows all fuel injectors good

clear code and it comes back after 40 mph or so

changed air filter
changed fuel filter
changed crank sensor
changed cam sensor

used to get 16-18 mpg now 14.1 mpg

will check compression on all cylinders next

could it be a cracked head or leaking head gasket ?
I have no extra water in oil
no extra oil in water
no extra shoot up pressure when the radiator cap is off
oil is regular color not whitish
plugs when pulled did not have discoloration on them

next idea ?
Should i get pcm reprogrammed ?

 

[Richard Lewis]

what does number six plug look like , also make sure coil is inside of boot and didnts fall out somewhere in your garage it happened to me lol and it was a ***** to diaganose i kept getting a number 3 missfire and couldnt figure it out so i was about to pull the engine apart when i took the coil off i found the spring in the boot was missing. I dont think its your head gasket but a compression test will comfirm that also check the lash adjusters it could be bad and causing loss of compresion. also on mine ive had my number 5 cylinder miss fire from a bad oxygen sencor wich was another hard one to diaganose

 

[mdec950]

changed out crankshaft and camshaft sensors today
and a new fuel filter

that took 5 minutes on the sensors and 30 on that big port of the fuel filter
it was a hard one even with the disconnect wrench

cleared codes drove it
under 45 mph it was fine for 15 mintues

i went up to 65 and the light came on check engine

and all IM's were ok at that time
ANY OTHER IDEAS ?


I will pull the #6 plug and make sure its clean
and check for a spring too


And thanks for all of the suggestions and HELP

 

[mdec950]

and took off maf sensor and cleaned with maf sensor spray used air to blow it dry
no change

 

[Richard Lewis]

try changing the front 02 sencor on bank 2

 

[mdec950]

i have all 4 o2 sensors ordered from ebay along with a compression hose to fit this spark plug hole