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roy
roy, import/domestic specialest
Category: Ford
Satisfied Customers: 5713
Experience:  ASE master tech for 40 years
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Have a 5.4l that lost all compression on #3 hole everyone

Customer Question

have a 5.4l that lost all compression on #3 hole everyone thinkd the exhaust valve is not closing
JA: How many miles are on the car? How has your mileage been lately?
Customer: 120000
JA: What is the model/year of your Ford?
Customer: 2004 f150
JA: Are you fixing your F150 yourself? What have you tried so far?
Customer: yes, compression check all cylinders and all have 150-160lbs except #3. Has been parked for a couple years when it was shut off everything worked great. Have the cover off now going to check rocker arms
JA: Anything else you want the mechanic to know before I connect you?
Customer: not that i can think of
Submitted: 9 months ago.
Category: Ford
Expert:  roy replied 9 months ago.

good afternoon my name is ***** ***** I will assist

at number 3 cylinder, did you remove the followers and see if the valve is stuck open???

Roy

Customer: replied 9 months ago.
Have the followers off now
Expert:  roy replied 9 months ago.

ok, and

Customer: replied 9 months ago.
i dont believe it is
Expert:  roy replied 9 months ago.

one valve will be taller than the other

Expert:  roy replied 9 months ago.

ok, either you have a bad lifter that may have hung it open or the valve is open just enough not to seal. I doubt it is burnt since it ran good before

Roy

Expert:  roy replied 9 months ago.

try a compression test now

Customer: replied 9 months ago.
the exhaust valve is taller
Expert:  roy replied 9 months ago.

then the intake is the one open

soak it with pb blaster and work it up and down. if it does not free up the head will have to come off and the valve removed and the guide cleaned out

Roy

Expert:  roy replied 9 months ago.

please dont forget to rate me as it is the only way I get paid for my efforts

Roy

Expert:  roy replied 9 months ago.

please dont forget to rate me as it is the only way I get paid for my efforts

Roy