misfire .. here is what I have done.. suggestions. *** HELP ***
03-17-2019, 04:10 PM
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misfire .. here is what I have done.. suggestions. *** HELP *** so, I connected my laptop to my engine computer and watched real time misfires on cylinder 1 just roll in using HP tuner. the other cylinders had misfires but not as many and when I bring the RPM above 2800 they all clear up except for cylinder #1 and thats normal as I have an aggressive cam.. but past 3000RPM's cylinder #1 continues to misfire, fast counts coming in. I suspected it was a dead cylinder. I can hear a slight ticking noise.. thinking maybe spark jumping
I pull the spark plug and it has the normal burn look, it essentially looked the same as the other spark plugs. none-the-less, I changed the plugs,wires, and swapped the coil with another cylinder. fired it back up and nothing has changed, still constant misfires rolling in. I get a noid injector lite and it shows the injector is getting proper signal. I run a compression test and it sits pretty at 180lbs.
I pull the valve cover and slowly rotate the engine by hand. .I watch the rocker arms moving and when cylinder 1 intake valve goes about 1/2 way it slowly starts coming back up on its own.
So, it appears I have a problem with a lifter. There is no slack at the rocker arm at all, it is never lose in the whole rotation of engine.
question: has anybody had this happen to them? am I stuck pulling the head and replacing the lifter? or is there anything that can be done ( wishing upon a start right now guys. help.. :/ )
I pull the spark plug and it has the normal burn look, it essentially looked the same as the other spark plugs. none-the-less, I changed the plugs,wires, and swapped the coil with another cylinder. fired it back up and nothing has changed, still constant misfires rolling in. I get a noid injector lite and it shows the injector is getting proper signal. I run a compression test and it sits pretty at 180lbs.
I pull the valve cover and slowly rotate the engine by hand. .I watch the rocker arms moving and when cylinder 1 intake valve goes about 1/2 way it slowly starts coming back up on its own.
So, it appears I have a problem with a lifter. There is no slack at the rocker arm at all, it is never lose in the whole rotation of engine.
question: has anybody had this happen to them? am I stuck pulling the head and replacing the lifter? or is there anything that can be done ( wishing upon a start right now guys. help.. :/ )
03-17-2019, 04:28 PM
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IF it's the lifter, the head must come off to change it. Not much choice there.
03-17-2019, 04:42 PM
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yeah.. 
i know.. :*( I dont want to though.. LOL
if I pop one head off because of bad lifter, I might as well pop the other head off and replace them all.
as a mater of fact, I have not backed off the rocker yet.. and re-set/adjusted the rocker arm. Maybe a slight change it was not set to 3/4 to 1 full turn from no lash?
Looking for *anything* that I could check before I start a teardown.
i know.. :*( I dont want to though.. LOLif I pop one head off because of bad lifter, I might as well pop the other head off and replace them all.
as a mater of fact, I have not backed off the rocker yet.. and re-set/adjusted the rocker arm. Maybe a slight change it was not set to 3/4 to 1 full turn from no lash?
Looking for *anything* that I could check before I start a teardown.
