My 98 f150 has a miss on cylinder 3 [ code 303 ] i have changed wires , plugs ,coilpack , and the injector with no results . Does anybody have an idea what it could be ? The compresion is good on all cylinders .PLEASE HELP

 

Do you have the correct information posted?? Or just a typo?? P0303 is cylinder number 3 misfire.

 

sorry you are right its cylender 3 . Dont know what I was thinking

 

What size engine? The V8 is known for losing a cam follower causing a misfire. Is it still missing or is it just the code coming back? What is the compression readings on all cylinders? Sorry for the questions.

 

If its the V6, verify you are not also loosing engine coolant. My 1997 and a misfire code along with coolant loss and I had to replace the lower intake manifold gaskets. Basically a 4 to 5 hour job.

 

v6 4.2 lower manifold gasket leaking coolant into cylinder1and3 found it when i checked compression Thanks for the help

 

Thanks for the fixed post. We do not get that enough.

 

No problem.. This site is where someone told me what was wrong with my engine. Glad to hear your running again.

romeodz